In the United States, when someone has a medical emergency, we take for granted that an ambulance will arrive. It will get to some places faster than others—a disparity driven by wealth and other factors. Still, by calling 911, we’re immediately connected to a vast fleet of emergency vehicles plugged into a system that’s designed to get people to hospitals in times of crisis.

But what about countries where ambulances aren’t readily accessible? What about places where even cars are scarce, where the nearest hospital with surgical capacity might be 100 miles away down an unpaved road, and where a family facing a medical crisis has no reliable way to get there or pay for the journey?

This is the reality for millions of pregnant women across sub-Saharan Africa.

Thanks to modern medicine, we now know how to prevent most maternal and newborn deaths. And maternal mortality has declined by 40 percent over the last two decades as a result. But hundreds of thousands of women and babies still die every year from complications during pregnancy and childbirth, because they can’t get to a place where someone can treat them in time.

In maternal health, this problem is called the “second delay.” It’s a terrible tragedy, one that the Gates Foundation has been trying to address for years.

Back in 2013, partners including Vodafone Foundation and local health organizations started tackling this problem by asking a simple question in rural Tanzania: What if you could create something like a 911 system that worked with whatever transportation was available in a community? They tested the idea in a few districts, and it worked well enough that they decided to scale it up. They called it m-mama.

m-mama works like this: When a community healthcare worker identifies an emergency—maybe it’s severe bleeding after delivery, or a premature baby who can’t breathe—they call a free hotline. A trained nurse dispatcher uses an app to figure out what kind of care is needed and where it’s available, then coordinates whatever transportation makes sense for that location (a community driver with a car where there are good roads, a motorcycle where there aren’t, a boat for island communities, even a horse for mountainous terrain.) The dispatcher stays on top of everything, tracking the journey, alerting the receiving facility, and handling payment at the end.

The numbers speak for themselves. Since 2013, m-mama has responded to more than 125,000 emergencies and saved an estimated 5,266 lives. And in regions where m-mama launched, maternal emergency transports more than doubled. That means there was a massive need that was going unmet for far too long. About 58% of the deliveries transported by m-mama end up requiring a C-section, compared to the 10-15% you would expect in the general population. These are genuinely high-risk cases that would have likely ended in tragedy without emergency transport.

What’s especially impressive about m-mama’s impact is that it hasn’t required building new hospitals or buying any expensive equipment. Instead, it makes existing health systems work better by coordinating resources that are already there—ambulances, facilities, healthcare workers—and filling gaps with options that cost a fraction of what traditional ambulances do.

And it is scaling. m-mama started as a pilot serving 750,000 people and now reaches 62 million in Tanzania. It’s gone nationwide in Lesotho. It just launched in Malawi and is scaling up in Kenya. There are plans for more countries across sub-Saharan Africa, supported in part by the Beginnings Fund—a partnership that includes our foundation, the Mohamed bin Zayed Foundation for Humanity, and other organizations working to improve maternal and newborn health across Africa.

The program is financially sustainable too. Once the program is up and running, the governments cover operating costs. m-mama has proven it can be owned and run locally, which is the only way something like this works long-term.

m-mama is a reminder that not all breakthroughs in global health are new drugs or sophisticated technology. Sometimes they’re just smart ways of getting the right care to the right person at the right time. When a mother or baby is in crisis, minutes can make the difference between life and death.

m-mama is making sure those minutes count.

A core principle underlying the Gates Foundation’s work is closing the innovation gap between rich countries and everyone else. People in poorer parts of the world shouldn’t have to wait decades for new technologies to reach them. That’s why we've worked for 25 years to accelerate access to life-saving medicines and vaccines in low- and middle-income countries.

It's also why, today, the Gates Foundation and OpenAI are announcing an initiative called Horizon1000 to support several countries in Africa, starting in Rwanda, as they apply AI technology to improve their health care systems.

Over the next few years, we will collaborate with leaders in African countries as they pioneer the deployment of AI in health. Together, the Gates Foundation and OpenAI are committing $50 million in funding, technology, and technical support to back their work. The goal is to reach 1,000 primary healthcare clinics and their surrounding communities by 2028.

Today’s AI can help save lives

A few years ago, I wrote that the rise of artificial intelligence would mark a technological revolution as far-reaching for humanity as microprocessors, PCs, mobile phones, and the Internet. Everything I’ve seen since then confirms my view that we are on the cusp of a breathtaking global transformation.

All over the world, AI, in the form of LLMs and machine learning models, are improving far more quickly than I first anticipated. From science to education to customer service and more, AI tools are reshaping every facet of our lives.

I spend a lot of time thinking about how AI can help us address fundamental challenges like poverty, hunger, and disease. One issue that I keep coming back to is making great health care accessible to all—and that’s why we’re partnering with OpenAI and African leaders and innovators on Horizon1000.

Not enough doctors in the house

We have seen amazing successes in global health over the past 25 years: child mortality has been cut in half, and there are now real pathways to eliminating or controlling deadly diseases like polio, malaria, TB, and HIV. But one stubborn problem that keeps slowing progress is the desperate shortage of health care workers in poorer parts of the world.

In Sub-Saharan Africa, which suffers from the world’s highest child mortality rate, there is a shortfall of nearly 6 million health care workers, a gap so large that even the most aggressive hiring and training efforts can’t close it in the foreseeable future.

These huge shortages put health care workers in these countries in an impossible situation. They’re forced to triage too many patients with too little administrative support, modern technology, and up-to-date clinical guidance. Partly as a result, the WHO estimates that low-quality care is a contributing factor in 6 to 8 million deaths in low- and middle-income countries every year, and that’s not even counting the millions who die because they aren’t able to access health care at all.

Rwanda leads the way

Today’s AI can help save those lives by reaching many more people with much higher-quality care.

Rwanda currently has only one health care worker per 1,000 people, far below the WHO recommendation of about four per 1,000. It would take 180 years for that gap to close at the current pace of progress. So, as part of the 4x4 reform initiative, Minister of Health Dr. Sabin Nsanzimana recently announced the launch of an AI-powered Health Intelligence Center in Kigali to help ensure limited health care resources are being used as wisely as possible.

As part of the Horizon1000 initiative, we aim to accelerate the adoption of AI tools across primary care clinics, within communities, and in people’s homes. These AI tools will support health workers, not replace them.

On the horizon

Minister Nsanzimana has called AI the third major discovery to transform medicine, after vaccines and antibiotics, and I agree with his point of view. 

If you live in a wealthier country and have seen a doctor recently, you may have already seen how AI is making life easier for health care workers. Instead of taking notes constantly, they can now spend more time talking directly to you about your health, while AI transcribes and summarizes the visit. Afterwards, AI can handle much of the onerous paperwork, so doctors and nurses can focus on the next patient.

In poorer countries with enormous health worker shortages and lack of health systems infrastructure, AI can be a gamechanger in expanding access to quality care. I believe this partnership with OpenAI, governments, innovators, and health workers in sub-Saharan Africa is a step towards the type of AI we need more of: systems that help people all over the world to solve generational challenges that they simply didn’t know how to address before. I invite others working on AI to think about how we can put these massively powerful tools to the best use.

This announcement is a great example of why I remain optimistic about the improvements we can make. I’m looking forward to seeing health workers using some of these AI solutions in action when I visit Africa, and I plan to continue focusing on ways AI technology can help billions of people in low- and middle-income countries meet their most important needs.

I’ve been working in global health for two and a half decades now, and the transformation in how we fight HIV/AIDS is one of the most remarkable achievements I’ve witnessed. (It’s second only to how vaccines have saved millions of children's lives.)  

At the dawn of the AIDS epidemic, an HIV diagnosis was often a death sentence. But in the years since, so much has changed. Today, not only do we have anti-retroviral medications that allow people with HIV to live full, healthy lives with undetectable viral loads—meaning they can’t transmit the virus to others. We also have powerful preventative medications known as PrEP, or pre-exposure prophylaxis, that can reduce a person’s risk of contracting the virus by up to 99 percent when taken as prescribed. It’s an incredible feat of science: a pill that virtually prevents HIV contraction.

In theory, if we could get these tools to everyone who needs them and make sure they’re used correctly, we could stop HIV in its tracks. Because when people with the virus receive proper treatment, they can’t transmit it to others. And when people at risk take PrEP, they can’t contract it. In practice, however, getting these tools to people—and making sure they’re used correctly—is the hard part. Especially for PrEP.  

That’s because current preventatives require people to take medication every single day. Miss a dose, and protection drops. It’s like trying to remember to lock your front door 365 times a year—if you mess up once, you’re vulnerable. For many people, the barriers stack up quickly. Some have to walk hours to reach a clinic. Others struggle to store medication safely or discreetly at home. And many face judgment and stigma for taking PrEP, especially young women in conservative communities. The very act of protecting yourself can lead to being shamed or ostracized. 

That’s why I’m so excited about a new wave of innovations in HIV prevention. Scientists are in the process of developing several longer-lasting PrEP breakthroughs, each with distinct advantages that could help more people protect themselves on their own terms. 

Lenacapavir, which requires only two doses per year through injection, could open HIV prevention up to people who can’t make frequent clinic visits. Cabotegravir, another injectable option that works for two months at a time, offers a more flexible dosing schedule than daily PrEP pills, too. Meanwhile, a monthly oral medication called MK-8572, still in the trial stage, could provide an alternative for people who prefer pills to injections. The Gates Foundation is even exploring ways to maintain a person’s protection for six months or longer. And researchers are working on promising PrEP options that include contraception, which would be particularly valuable for women who need both types of protection. 

To understand how these options work in real life, and not just in labs, our foundation has supported implementation studies in South Africa, Malawi, and elsewhere. Unlike traditional clinical trials that test safety and efficacy in highly controlled settings, these studies examine how medications fit into people’s lives and work in everyday circumstances—looking at ease of use, cultural acceptance, and other practical challenges. This real-world understanding is crucial for successful adoption.  

Some people ask me if these new preventative tools mean the Gates Foundation has given up on finding an HIV vaccine. Not at all. In fact, these advances push us to aim even higher in our research for a vaccine that could prevent HIV for a lifetime—and not just a few months at a time. Our goal is to create multiple layers of protection, much like modern cars have seatbelts, airbags, and even collision-warning sensors. Different tools work better for different people in different ways, and we need every tool we can get. 

But even the most brilliant innovations make no difference unless they reach the people who need them most. This is where partnerships become crucial. Through grants to research institutions around the world, the foundation is working to lower manufacturing costs for HIV drugs so they’re accessible to everyone, everywhere. Then there are organizations like the Global Fund and PEPFAR, which have been instrumental in turning scientific advances into real-world impact.  

The Global Fund—which needs to raise significant new resources next year to continue its work—currently helps more than 24 million people access HIV prevention and treatment. And PEPFAR has saved 25 million lives since its inception in 2003—a powerful example of how American leadership can build tremendous goodwill while transforming the world. Motivated by the belief that no person should die of HIV/AIDS when lifesaving medications are available, President George W. Bush created PEPFAR with strong bipartisan backing and it continues to serve as a lifeline to millions of people.  

We're at a pivotal moment in this fight. Twenty years ago, many believed it would be impossible to deliver HIV treatment at scale in Africa’s poorest regions. Since then, we’ve made fantastic progress. Science has shown us promising paths forward—for better prevention options, easier treatment regimens, and, maybe one day, an effective vaccine. Our task now? Ensuring the life-saving innovations we already have reach the people whose lives they can save. 

When most Americans think of polio, we probably picture President Franklin Delano Roosevelt. In 1921, at age 39, he was paralyzed by the virus and never regained the use of his legs. His story helped turn polio into a national cause. But in many ways, his experience was an anomaly.

After all, polio is overwhelmingly a childhood disease, with the vast majority of cases affecting those younger than five. That was true when FDR fell ill, and it’s true today. The typical patient isn’t an adult with an already established political career—it’s a little kid, often a little kid in a low-income country, who might never get the chance to take his first steps.

That injustice is one big reason I've spent the past two decades working to eradicate polio. The other reason is that eradication is actually possible, realistic, and well within reach. This is a disease we can get rid of—not just control, but eliminate everywhere. That is a rarity in global health.

The world has already made extraordinary progress. Back in 1988, when Rotary International and the World Health Assembly set the goal of eradication, the virus was paralyzing more than 350,000 children each year across 125 countries. Since then, cases have dropped by 99.9 percent. The strains known as Type 2 and Type 3 wild poliovirus have been eradicated. The entire African continent is certified wild-polio free. Only two countries—Afghanistan and Pakistan—still have persistent transmission of Type 1 wild poliovirus.

Now we're closer than ever to total polio eradication. But the last mile is proving the hardest because viruses find ways to exploit any immunity gaps or weaknesses. Wherever vaccination rates slip—even briefly—they can resurface.

One of the biggest challenges comes from what are called variant outbreaks. In communities where immunization is low, the weakened virus used in the oral polio vaccine can circulate asymptomatically and rarely, over time, mutate enough to regain the ability to cause paralysis in unvaccinated children.

While most variant outbreaks happen in places with extremely low vaccination coverage, poor sanitation, and weaker health systems, no place is risk-free until the world is polio-free. In 2022, the United States confirmed its first paralytic polio case in nearly a decade, and the virus was detected in New York wastewater samples. In the time since, variant polioviruses have also been found in the U.K., Ukraine, Indonesia, and other countries.

The good news is that today’s tools are better than anything we had even five years ago, and they make every dollar spent on the cause go further than ever before. We have a new oral vaccine, nOPV2, that’s far less likely to mutate and lead to new variant outbreaks; nearly two billion doses have already been given worldwide. New regional labs in Ghana, Nigeria, South Africa, and Uganda that test wastewater samples and sequence viruses have cut detection times by over 30 percent, which gives health workers a critical head start on outbreak response. And the surveillance network for polio is one of the most sophisticated ever built—also helping alert public health officials to outbreaks of cholera, measles, Ebola, and even COVID-19 at the height of that pandemic.

The Gates Foundation has been proud to support these advances as part of the Global Polio Eradication Initiative, a coalition of the WHO, UNICEF, the CDC, Gavi, Rotary International, and dozens of countries’ governments. It’s one of the most successful collaborations in the history of global health.

But right now, GPEI is facing a $1.7 billion funding gap, with various long-term donor governments cutting back their support. Without the right resources, vaccination campaigns may have to be scaled back, surveillance sites will likely close, and the virus could spread globally.

In the century since FDR was paralyzed by the virus, American leadership and generosity have helped turn polio into a fight the whole world could win. From the March of Dimes, which funded research, to the development of the first vaccines, to support for eradication campaigns, U.S. commitment has been decisive.

The world is at the brink of ending this terrible disease, and the stakes of this moment couldn’t be higher. If we finish the job, we free up billions of dollars for other health priorities and—most importantly—protect generations of children from a virus that has paralyzed millions. If we back down from the fight, up to 200,000 children could be paralyzed each year within a decade.

We have the scientific tools and infrastructure needed to cross the finish line. And we have hundreds of thousands of committed vaccinators who are determined to get us there—who go door to door across deserts, jungles, floodplains, and war zones to make sure no child is missed. I've met them, I've heard their stories, and I've seen how determined they are to finish the job.

We should be too.

I spend a lot of time thinking and worrying about malaria. After all, it’s one of the big focuses of my work at the Gates Foundation. But for most Americans, the disease is a distant concern—something that happens “there,” not here.

That’s true today. It wasn’t always.

It was especially rampant in the South, from the Carolinas and the Mississippi Delta down to Florida and all along the Gulf Coast.

Every summer, people braced for the start of “fever season.” In her Little House on the Prairie books, Laura Ingalls Wilder wrote about what she called “fever ‘n’ ague.” A laundry list of presidents—including George Washington, Andrew Jackson, Abraham Lincoln, and Ulysses S. Grant—battled the disease.

During the Civil War, Confederate General Robert E. Lee was even counting on malaria to weaken Union troops, confident that “the climate in June will force the enemy to retire.” (It ended up crippling his own army more.)

Without modern medicine, or any understanding of how the disease spread, people reached for whatever remedies they could find: drinking vinegar and whiskey, rubbing onions on their skin, and boiling bitter herbs into tea. Powdered quinine, a substance derived from cinchona bark, actually worked—but it was expensive and hard to obtain, so few people had access to it.

For most people, the fevers kept returning year 
after year and summer after summer.

The first breakthrough came at the turn of the 20th century. Scientists finally proved that malaria was transmitted by mosquitoes—not, as had been previously thought, by contaminated water or poor air quality. (Malaria means “bad air” in medieval Italian.) It was a crucial discovery. Finally, people knew what to target. Across the South, some communities began draining swamps to try to control their mosquito populations. But most of these efforts were basic and improvised. What was needed was the kind of massive, coordinated, well-funded approach that only the federal government could mount. Enter one of the most ambitious and impactful infrastructure projects in American history: the Tennessee Valley Authority.

Enter one of the most ambitious and impactful infrastructure projects in American history


the Tennessee Valley Authority.

The TVA wasn’t created to fight malaria. Launched in 1933 as part of the New Deal, its mission was mainly economic: to bring electricity and jobs to the rural South, where some of the country’s poorest people lived, during the Great Depression. But the region also had some of the nation’s highest malaria rates, with 30 percent of its population infected. TVA leaders quickly realized their work wouldn’t succeed unless public health improved too.

So they incorporated malaria prevention into their projects. As engineers built dams and power plants across the region, they also drained thousands of acres of swamps, reshaped rivers, regraded land, and upgraded housing—which all helped to destroy mosquito breeding grounds. At the same time, public health campaigns educated people on installing window screens and eliminating standing water around their homes after storms. Then came World War II.

Then Came


world war II

As military bases popped up across the South, malaria became a growing threat to soldiers and defense industry workers. So the U.S. responded by launching a new program in 1942: the Office of Malaria Control in War Areas, headquartered in Atlanta. It was the federal government’s first centralized program created explicitly to fight malaria—and it laid the groundwork for what would become the Centers for Disease Control and Prevention, or CDC, which officially took over the malaria effort in 1947.

The goal of the campaign, which began with wartime control before transitioning to peacetime eradication, was simple but ambitious: Stop mosquitoes from spreading malaria, and stop people from carrying it.

ON THE MOSQUITO FRONT

The campaign launched the largest insecticide operation in U.S. history and paired it with an aggressive effort to destroy mosquito breeding grounds. Teams of sprayers went door-to-door with tanks of DDT strapped to their backs, covering millions of homes in what was essentially a chemical shield against mosquitoes. In some areas, airplanes dusted entire counties with insecticide. Meanwhile, construction crews drained ditches by hand or with bulldozers. In Florida, they used dynamite to blast open drainage paths from mosquito-infested marshland.

ON THE HUMAN SIDE

Quinine and later chloroquine—its synthetic successor—were distributed widely, especially in rural areas with high infection rates. These drugs cleared the parasite from the bloodstream, which meant that even if someone was bitten by a mosquito, they wouldn’t pass the disease on. Mobile teams traveled from town to town, testing and treating entire communities. In the Mississippi Delta, they even set up roadside treatment stations where people could stop for a dose on the way to work or school.

Public health messaging played a huge role, too. One memorable cartoon featured a mosquito named Bloodthirsty Ann—yes, short for Anopheles—that taught troops how to reduce their risk of contracting malaria. Its creator was a young army captain named Theodor Geisel, who eventually became better known as Dr. Seuss.

Perhaps the most impressive part of the program was its scale and speed. In just a few years, tens of thousands of public health workers across fifteen states were hired and trained. Doctors, nurses, scientists, teachers, technicians, and trusted community figures knocked on doors, gathered data, treated patients, and made sure no outbreak went unchecked. In 1951, America declared victory over malaria.

In 1951


AMERICA DECLARED VICTORY OVER MALARIA

I think about this history a lot when I’m visiting Sub-Saharan Africa, where the parasite still kills 600,000 people a year. Because in many ways, the strategy hasn’t changed: Stop transmission, clear infections, and build public health systems that prevent malaria from roaring back.

Malarious area of the United States 

But the U.S. had some key advantages that made elimination much easier. Compared to the species responsible for most malaria today, our mosquitoes weren’t as efficient at transmitting the parasite. Our climate also limited transmission to the summer months; in tropical regions, people get infected year-round. And by the 1940s, our country had relatively strong infrastructure, even in rural areas, that many malaria-endemic countries today still lack.

ON THE TREATMENT SIDE

So the challenge today is much bigger. Fortunately, today’s malaria-fighting toolbox is much bigger—and better—too.

Instead of blanket spraying DDT, which has since been banned, modern prevention relies on safer insecticide-treated bed nets and indoor spraying techniques that use smaller doses of more targeted chemicals. Sugar baits, which lure mosquitoes to ingest a lethal dose of insecticide, are already helping reduce their numbers. And gene drive technology could soon block the parasite inside the mosquito itself—so even if someone gets bitten, they won’t get infected.

Chloroquine has been replaced by artemisinin-based combination therapies, or ACTs, which are more effective and less prone to resistance. New drugs like tafenoquine are helping eliminate recurring strains. Seasonal chemoprevention protects children during peak transmission months. And the first malaria vaccine has been approved, with more on the way.

Malaria elimination is never easy. But unlike a century ago, it’s no longer a mystery. The world knows how to stop this disease. We’ve done it before. And with the right investments and innovations, we can do it again—this time, for everyone.

I’ve been working in global health for 25 years—that’s as long as I was the CEO of Microsoft. At this point, I know as much about improving health in poor countries as I do about software. 

I’ve spent a quarter-century building teams of experts at the Gates Foundation and visiting low-income countries to see the work. I’ve funded studies about the effectiveness of health aid and pored over the results. I’ve met people who were on the brink of dying of AIDS until American-funded medicines brought them back. And I’ve met heroic health workers and government leaders who made the best possible use of this aid: They saved lives. 

The more I’ve learned, the more committed I’ve become. I believe so strongly in the value of global health that I’m dedicating the rest of my life to it, as well as most of the $200 billion the foundation will give away over the next 20 years.  

People in global health argue about a lot of things, but here’s one thing everyone agrees on: Health aid saves lives. It has helped cut the number of children who die each year by more than half since 2000. The number used to be more than 9 million a year; now it’s fewer than 5 million. That’s incontrovertible.  

So when the United States and other governments suddenly cut their aid budgets the way they've been doing, I know for a fact that more children will die. We’re already seeing the tragic impact of reductions in aid, and we know the number of deaths will continue to rise.

A study in the Lancet looked at the cumulative impact of reductions in American aid. It found that, by 2040, 8 million more children will die before their fifth birthday. To give some context for 8 million: That's how many children live in California, Texas, Florida, New York, Pennsylvania, and Ohio combined. 

I’ve submitted written testimony on this topic, which you can read below, for the Senate Appropriations Committee hearing occurring later today. In it, I discuss what’s already happened and what needs to happen next.

Testimony to the United States Senate Committee on Appropriations
June 25, 2025

Over the past 25 years—the same span of time I spent leading Microsoft—I have immersed myself in global health: building knowledge, deepening expertise, and working to save lives from deadly diseases and preventable causes. During that time, I have built teams of world-class scientists and public health experts at the Gates Foundation, studied health systems across continents, and worked in close partnership with national and local leaders to strengthen the delivery of lifesaving care. I have visited hundreds of clinics, listened to frontline health workers, and spoken with people who rely on these programs. Earlier this month, I traveled to Ethiopia and Nigeria, where I witnessed firsthand the impact that recent disruptions to U.S. global health funding are having on lives and communities.

Global health aid saves lives. And when that aid is withdrawn—abruptly and without a plan—lives are lost.

Yet, in recent months, some have questioned whether the foreign assistance pause has caused harm. Concerns about the human impact of these disruptions have been dismissed as overstated. Some people have even claimed that no one is dying as a result.

I wish that were true. But it is not.

It is important to note that while this hearing is about the Trump Administration’s $9 billion recission package, what is really at stake is tens of billions of dollars in critical aid and health research that has been frozen by DOGE with complete disregard for the Congress and its Constitutional power of the purse.

In the early weeks of implementing the foreign aid freeze, DOGE directives resulted in the dismissal of nearly all United States Agency for International Development (USAID) staff and many personnel at the Centers for Disease Control and Prevention (CDC). Some funding was later restored to allow for the continuation of what has been categorized as "lifesaving" programs. However, to date that designation has been applied narrowly and with limited transparency, in an inconsistent manner, often prioritizing emergency interventions when a patient is already in critical condition over essential preventative or supportive care.

For example, providing a child with a preventive antimalarial treatment, ensuring access to nutrition so that HIV/AIDS medications can be properly administered, testing pregnant women for HIV to see if they are eligible for treatment to prevent transmission to their children or identifying and treating tuberculosis cases early have not consistently qualified for exemption. As a result, many of the programs delivering these services have been suspended, delayed, or scaled back.

Recent reporting from the New York Times has shed light on the devastating human cost of the abrupt aid cuts. One especially tragic example is Peter Donde, a 10-year-old orphan in South Sudan, born with HIV, who died in February after losing his access to life-saving medication when USAID operations were suspended. His story is one of many.

During my recent visit to Nigeria, I met with leaders from local nonprofit organizations previously funded by the United States. One group shared the remarkable progress they had made in tuberculosis detection and treatment. In just a few years, case identification increased from 25 percent to 80 percent, a critical step toward breaking transmission and reducing the overall disease burden. That progress has now stalled. The grants that enabled this work were tied to USAID staff who have been dismissed, and with their departure, the funding ended, and the work stopped.

The broader effects of these sudden shifts are difficult to overstate. For example, funding for polio eradication has been preserved in the State Department budget but cut from the CDC—even though the two agencies collaborate closely on the program. This type of fragmented decision-making has left implementing organizations uncertain about staffing and operations. Many no longer feel confident that promised U.S. funds will materialize, even when awards have been announced. In some cases, staff continue to work without pay. Some organizations are approaching insolvency.

Meanwhile, in warehouses across the globe, food aid and medical supplies sourced from American producers are sitting idle—spoiling or approaching expiration—because the systems that once distributed them have been disrupted. Clinics are closing. Health workers are being laid off. HIV/AIDS patients are missing critical doses of medication. Malaria prevention campaigns, including bed net distributions and indoor spraying, have been delayed or canceled, leaving hundreds of millions of people unprotected at the peak of transmission season.

Efforts to track data that would illustrate the severity of this worsening crisis have also been severely compromised. Many of the people responsible for collecting and reporting health information—health workers, statisticians, and program managers—have been laid off or placed on leave. The systems that once monitored health outcomes are shutting down, and the offices where that data was once analyzed now sit empty. As a result, the true scope of the harm is becoming harder to measure, just as the need for information is most urgent.

The situation we face is not about political ideology, and it is not a debate over fiscal responsibility. U.S. government spending on global health accounts for just 0.2 percent of the federal budget. Shutting down USAID did nothing to reduce the deficit. In fact, the deficit has grown in the months since.

Furthermore, many of the allegations regarding waste, fraud, and abuse have proven to be unsubstantiated. For example, the widely circulated claim that USAID sent millions of dollars’ worth of condoms to the Gaza Strip is inaccurate. In fact, the Wall Street Journal reported that the program allocated approximately $27,000 for condoms as part of an HIV transmission prevention initiative—not in the Middle East, but in Gaza Province, Mozambique.

What we are witnessing because of the rapid dismantling of America’s global health infrastructure is a preventable, human-caused humanitarian crisis—one that is growing more severe by the day. DOGE made a deadly mistake by cutting health aid and laying off so many people. But it is not too late to undo some of the damage.

A Record of Progress—and What is at Risk

Since 2000, child mortality worldwide has been cut in half. Deaths from HIV/AIDS, tuberculosis, and malaria have declined significantly. And we are on the verge of eradicating only the second human disease in history: polio. These are not abstract statistics; they represent tens of millions of lives saved. None of this progress would have been possible without consistent, bipartisan U.S. leadership and investment.

Over the past several decades, the United States has built one of its most strategic global assets: a respected and robust public health presence. This leadership is not just a humanitarian achievement—it is a core pillar of American soft power and security. For example, a Stanford study analyzing 258 global surveys across 45 countries found that U.S. health aid is strongly linked to improved public opinion of the United States. In countries and years where U.S. health aid was highest, the probability of people having a very favorable view of the United States was 19 percentage points higher. Other forms of aid—like military or governance—did not have the same effect. Another example is the 2014 Ebola outbreak in West Africa. The rapid deployment of U.S. scientists, health workers, and CDC teams helped contain the virus before it could spread globally. Their presence allowed the U.S. to help shape the response strategy, speed up containment, and prevent a wider outbreak. Many African countries are facing the dual burden of rising debt and pressing health needs, forcing painful choices between repaying creditors, and protecting their citizens. Helping them navigate this challenge is not just the right thing to do—it is a strategic imperative. If the United States retreats, others will fill the gap, and not all of them will bring our values, our priorities, or our interests to the table. Preserving American global influence will require restoring the staff, systems, and resources that underpin it—before the damage becomes irreversible.

I understand the fiscal pressures facing Congress. I recognize the need to prioritize spending and to hold programs accountable for results. I also share the Trump Administration’s commitment to promoting efficiency and encouraging country-led solutions. But I believe those goals can—and must—be pursued while still protecting the programs that deliver the highest return on investment and the greatest impact on human lives.

The United States’ support for Gavi, the Vaccine Alliance; the Global Fund to Fight AIDS, Tuberculosis, and Malaria; the President’s Emergency Plan for AIDS Relief (PEPFAR); and the Global Polio Eradication Initiative (GPEI) represent some of the smartest, most effective investments our country has ever made. These initiatives are proven, strategically aligned with American interests, and cost-effective on a scale few other government programs can match.

Together, Gavi and the Global Fund have helped save more than 82 million lives. Gavi has helped halve childhood deaths in the world’s poorest countries and returns an estimated $54 for every $1 invested. The Global Fund has contributed to a 61% reduction in deaths from HIV/AIDS, TB, and malaria. PEPFAR has saved over 26 million lives and helped millions of children be born HIV-free. GPEI has brought us closer than ever to the eradication of polio. Pulling back now would not only jeopardize these historic gains—it would invite a resurgence of preventable disease, deepen global instability, and undermine decades of bipartisan American leadership.

This is not a forever funding stream for the U.S. Government. These programs set out clear pathways for countries to “graduate” from aid, which many have already done. For example, nineteen countries, including Viet Nam and Indonesia, have successfully graduated from Gavi support and now fully finance their own immunization programs. Others—from Bangladesh to Cote d'Ivoire—are on track to do the same. This is how U.S. development policy should work: catalytic, cost effective, and designed to help countries become self-reliant and drive their own progress. I agree that aid funding should have an end date, but not overnight. The most effective path to that end date is innovation. By investing in the development and delivery of new medical tools and treatments, we can drive down the cost of care, and in some cases, make diseases that were once a death sentence treatable, or even curable. Advances in therapies for chronic conditions like sickle cell disease, HIV, or certain types of cancers could transform lives and health systems. American innovation offers a sustainable exit strategy—one that reduces long-term costs, allows the United States to responsibly step back, and builds lasting trust and good will that far exceed the original investment.

Over the past 25 years, the Gates Foundation has invested nearly $16 billion in global health partnerships like Gavi, the Global Fund, and GPEI. We will continue to invest, through innovation, research, and close coordination with partners. But no private institution—or coalition of them—can replace the scale, reach, or authority of the U.S. government in delivering lifesaving impact at the global level.

The decisions made in the coming weeks will shape not only the lives saved in the near term—but the legacy of American leadership for generations to come.

Download a PDF of the testimony with appendices that include reflections from Gates Foundation staff in Africa on the impact of the U.S. aid cuts; analytical projections from respected organizations; and a selection of first-hand reporting from reputable news organizations and journalists.

When I first began thinking about how to give away my wealth, I did what I always do when I start a new project: I read a lot of books. I read books about great philanthropists and their foundations to inform my decisions about how exactly to give back. And I read books about global health to help me better understand the problems I wanted to solve.

One of the best things I read was an 1889 essay by Andrew Carnegie called The Gospel of Wealth. It makes the case that the wealthy have a responsibility to return their resources to society, a radical idea at the time that laid the groundwork for philanthropy as we know it today.

In the essay’s most famous line, Carnegie argues that “the man who dies thus rich dies disgraced.” I have spent a lot of time thinking about that quote lately. People will say a lot of things about me when I die, but I am determined that "he died rich" will not be one of them. There are too many urgent problems to solve for me to hold onto resources that could be used to help people.

That is why I have decided to give my money back to society much faster than I had originally planned. I will give away virtually all my wealth through the Gates Foundation over the next 20 years to the cause of saving and improving lives around the world. And on December 31, 2045, the foundation will close its doors permanently.

This is a change from our original plans. When Melinda and I started the Gates Foundation in 2000, we included a clause in the foundation’s very first charter: The organization would sunset several decades after our deaths. A few years ago, I began to rethink that approach. More recently, with the input from our board, I now believe we can achieve the foundation’s goals on a shorter timeline, especially if we double down on key investments and provide more certainty to our partners.

During the first 25 years of the Gates Foundation—powered in part by the generosity of Warren Buffett—we gave away more than $100 billion. Over the next two decades, we will double our giving. The exact amount will depend on the markets and inflation, but I expect the foundation will spend more than $200 billion between now and 2045. This figure includes the balance of the endowment and my future contributions. 

This decision comes at a moment of reflection for me. In addition to celebrating the foundation’s 25^th anniversary, this year also marks several other milestones: It would have been the year my dad, who helped me start the foundation, turned 100; Microsoft is turning 50; and I turn 70 in October.

This means that I have officially reached an age when many people are retired. While I respect anyone’s decision to spend their days playing pickleball, that life isn’t quite for me—at least not full time. I’m lucky to wake up every day energized to go to work. And I look forward to filling my days with strategy reviews, meetings with partners, and learning trips for as long as I can.

The Gates Foundation’s mission remains rooted in the idea that where you are born should not determine your opportunities. I am excited to see how our next chapter continues to move the world closer to a future where everyone everywhere has the chance to live a healthy and productive life.

Planning for the next 20 years

I am deeply proud of what we have accomplished in our first 25 years.

We were central to the creation of Gavi and the Global Fund, both of which transformed the way the world procures and delivers lifesaving tools like vaccines and anti-retrovirals. Together, these two groups have saved more than 80 million lives so far. Along with Rotary International, we have been a key partner in reviving the effort to eradicate polio. We supported the creation of a new vaccine for rotavirus that has helped reduce the number of children who die from diarrhea each year by 75 percent. Every step of the way, we brought together other foundations, non-profits, governments, multilateral agencies, and the private sector as partners to solve big problems—as we will continue to do for the next twenty years.

Over the next twenty years, the Gates Foundation will aim to save and improve as many lives as possible. By accelerating our giving, my hope is we can put the world on a path to ending preventable deaths of moms and babies and lifting millions of people out of poverty. I believe we can leave the next generation better off and better prepared to fight the next set of challenges.

The work of making the world better is and always has been a group effort. I am proud of everything the foundation accomplished during its first 25 years, but I also know that none of it would have been possible without fantastic partners.

Progress depends on so many people around the globe: Brilliant scientists who discover new breakthroughs. Private companies that step up to develop life-saving tools and medicines. Other philanthropists whose generosity fuels progress. Healthcare workers who make sure innovations get to the people who need them. Governments, nonprofits, and multilateral organizations that build new systems to bring solutions to scale. Each part plays an essential role in driving the world forward, and it is an honor to support their efforts.

Of course, although the Gates Foundation is by far the most significant piece of my giving, it is not the only way I give back. I have invested considerable time and money into both energy innovation and Alzheimer’s R&D. Today’s announcement does not change my approach to those areas.

Expanding access to affordable energy is essential to building a future where every person can both survive and thrive. The bulk of my spending in this area is through Breakthrough Energy, which invests in companies with promising ideas to generate more energy while reducing emissions. I also started a company called TerraPower to bring safe, clean, next-generation nuclear technology to life. Both of these ventures will earn profits if successful, and I will reinvest any money I make through them back in the foundation, as I already do today.

I support a number of efforts to fight Alzheimer’s disease and other related dementias. Alzheimer’s is a growing crisis here in the United States, and as life expectancies go up, it threatens to become a massive burden to both families and healthcare systems around the world. Fortunately, scientists are currently making amazing progress to slow and even stop the progress of this disease. I expect to keep supporting their efforts as long as it’s necessary.

The success in both areas will determine exactly how much money is given to the foundation since any profits they earn will be part of my overall gift.

What the Gates Foundation hopes to accomplish

Over the next twenty years, the foundation will work together with our partners to make as much progress towards our vision of a more equitable world as possible.

The truth is, there have never been more opportunities to help people live healthier, more prosperous lives. Advances in technology are happening faster than ever, especially with artificial intelligence on the rise. Even with all the challenges that the world faces, I’m optimistic about our ability to make progress—because each breakthrough is yet another chance to make someone’s life better.

Over the next twenty years, the foundation’s funding will be guided by three key aspirations:

In 1990, 12 million children under the age of 5 died. By 2019, that number had fallen to 5 million. I believe the world possesses the knowledge to cut that figure in half again and get even closer to ending all preventable child deaths.

We now understand the essential role nutrition—and especially the gut microbiome—plays in not only helping kids survive but thrive. We’ve made huge advances in maternal health, making sure that new and expectant mothers have the support they need to deliver healthy babies. We have new, life-saving vaccines and medicines, and we know how to get them to the people who need them most thanks to organizations like Gavi and the Global Fund. The innovation is there, the ability to measure progress is stronger than ever, and the world has the tools it needs to put all children on a good path.

Today, the list of human diseases the world has eradicated has just one entry: smallpox. Within the next couple years, I expect to add polio and Guinea worm to the list. (When we eradicate the latter, it will be a testament to the late President Jimmy Carter’s leadership.) I’m optimistic that, by the time the foundation shuts down, we can also add malaria and measles. Malaria is particularly tricky, but we’ve got lots of new tools in the pipeline, including ways of reducing mosquito populations. That is probably the key tool that, as it gets perfected and approved and rolled out, gives us a chance to eradicate malaria.

In 2000, the year that we started the foundation, 1.8 million people died from HIV/AIDS. By 2023, advances in treatment and preventatives cut that number to 630,000. I believe that figure will be reduced dramatically in the decades ahead, thanks to incredible new innovations in the pipeline—including a single-shot gene therapy that could reduce the amount of virus in your body so much that it effectively cures you. This would be massively beneficial to anybody who has HIV, including in the rich world. The same technology is also being used to treat sickle cell disease, an excruciating and deadly illness.

We’re also making huge progress on tuberculosis, which still kills more people than malaria and HIV/AIDS combined. Last year, a historic phase 3 trial began that could be the first new TB vaccine in over 100 years.

The key to maximizing the impacts of these innovations will be lowering their costs to make them affordable everywhere, and I expect the Gates Foundation will play a big role in making that happen. Health inequities are the reason the Gates Foundation exists. And the true test of our success will be whether we can ensure these life-saving interventions reach the people who need them most—particularly in Africa, South Asia, and across the Global South.  

To reach their full potential, people need access to opportunity. That’s why our foundation focuses on more than just health.  

Education is key. Frustratingly, progress in education is less dramatic than in health—there is no vaccine to improve the school system—but improving education remains our foundation’s top priority in the United States. Our focus is on helping public schools ensure that all students can get ahead—especially those who typically face the greatest barriers, including Black and Latino students, and children from low-income backgrounds. At the K-12 level, that means boosting math instruction and ensuring teachers have the training and support they need—including access to new AI tools that allow them to focus on what matters most in the classroom. Given the importance of a post-secondary degree or credential for success nowadays, we’re funding initiatives to increase graduation rates, too. 

As I mentioned, having access to a high-quality nutrition source is key to keeping kids’ development on track. Smallholder farmers form the backbones of local economies and food supplies, and they play a key role in making that happen. One of the main ways the foundation helps farmers is through the development of new, more resilient seeds that yield more crops even under difficult conditions. This work is even more important in a warming world, since no one suffers more from climate change than farmers who live near the equator. Despite that, I’m hopeful that we can help make smallholder farmers more productive than ever over the next two decades. Some of the crops our partners are developing even contain more nutrients—a win-win for both climate adaptation and preventing malnutrition.

We’ll also continue supporting digital public infrastructure, so more people have access to the financial and social services that foster inclusive economies and open, competitive markets. And we’ll continue supporting new uses of artificial intelligence, which can accelerate the quality and reach of services from health to education to agriculture.

Underpinning all our work—on health, agriculture, education, and beyond—is a focus on gender equality. Half the world’s smallholder farmers are women, and women stand to gain the most when they have access to education, health care, and financial services. Left to their own devices, systems often leave women behind. But done right, they can help women lift up their families and their communities.   

The United States, United Kingdom, France, and other countries around the world are cutting their aid budgets by tens of billions of dollars. And no philanthropic organization—even one the size of the Gates Foundation—can make up the gulf in funding that’s emerging right now. The reality is, we will not eradicate polio without funding from the United States.

While it's been amazing to see African governments step up, it’s still not enough, especially at a moment when many African countries are spending so much money servicing their debts that they cannot invest in the health of their own people—a vicious cycle that makes economic growth impossible.

It's unclear whether the world’s richest countries will continue to stand up for its poorest people. But the one thing we can guarantee is that, in all of our work, the Gates Foundation will support efforts to help people and countries pull themselves out of poverty. There are just too many opportunities to lift people up for us not to take them.

The last chapter of my career

Next week, I will participate in the foundation’s annual employee meeting, which is always one of my favorite days of the year. Although it’s been many years since I left Microsoft, I am still a CEO at heart, and I don’t make any decisions about my money without considering the impact. 

I feel confident putting the remainder of my wealth into the Gates Foundation, because I know how brilliant and dedicated the people responsible for using that money are—and I can’t wait to celebrate them.

I'm inspired by my colleagues at the foundation, many of whom have foregone more lucrative careers in the private sector to use their talents for the greater good. They possess what Andrew Carnegie called “precious generosity,” and the world is better off for it.

I am lucky to have been surrounded by many generous people throughout my life. As I wrote in my memoir Source Code, my parents were my first and biggest influences. My mom introduced me to the idea of giving back. She was a big believer in the idea of “to whom much is given much is expected,” and she taught me that I was just a steward of any wealth I gained.

Dad was a giant in every sense of the word, and he, more than anyone else, shaped the values of the foundation as its first leader. He was collaborative, judicious, and serious about learning—three qualities that shape our approach to everything we do. Every year, the most important internal recognition we hand out is called the Bill Sr. Award, which goes to the staff member who most exemplifies the values that he stood for. Everything we have accomplished—and will accomplish—is a testament to his vision of a better world.

As an adult, one of my biggest influences has been Warren Buffett, who remains the ultimate model of generosity. He was the first one who introduced me to the idea of giving everything away, and he’s been incredibly generous to the foundation over the decades. Chuck Feeney remains a big hero of mine, and his philosophy of “giving while living” has shaped how I think about philanthropy.

I hope other wealthy people consider how much they can accelerate progress for the world’s poorest if they increased the pace and scale of their giving, because it is such a profoundly impactful way to give back to society. I feel fulfilled every day I go to work at the foundation. It forces me to learn new things, and I get to work with incredible people out in the field who really understand how to maximize the impact of new tools.

Today’s announcement almost certainly marks the beginning of the last chapter of my career, and I’m okay with that. I have come a long way since I was just a kid starting a software company with my friend from middle school. As Microsoft turns 50 years old, it feels right that I celebrate the milestone by committing to give away the resources I earned through the company.

A lot can happen over the course of twenty years. I want to make sure the world moves forward during that time. The clock starts now—and I can’t wait to make the most of it.

I was excited to get a drone for my birthday last year. I couldn’t wait to get it into the air and see what my backyard looked like from the sky. But, as anyone who has used one can tell you, I quickly learned a harsh truth: Flying a drone isn’t easy. It takes a lot of practice and skill.

Maybe it’s time to pull the drone back out, because I was lucky to get a lesson from the experts last month in India. During my visit to Delhi, I met with Sangita Devi, Sumintra Devi, and Kajol Kumari—three Drone Didis from Bihar who are taking India’s agricultural productivity to new heights.

The women I met are part of the Indian government’s Namo Drone Didi program. (Didi is the Hindi word for “sister.”) It was launched in 2023 to help rural women boost their income and boost India’s agricultural productivity—and although the program is still in its early days, I’m already impressed by its results.

Right now, the Drone Didis primarily use their flying skills to fertilize crops. Applying fertilizer via drone has a lot of benefits over doing it by hand. Since you can spray farther away from the plant, the liquid fertilizer becomes more atomized—which means that it turns into finer droplets that cover more area. This benefits both farmers and the environment, because you need significantly less fertilizer and less water to help distribute it. Plus, it’s faster. One Drone Didi can cover as much as five acres in the same time it would take five people to cover half an acre.

I cannot wait to see how the program expands in the years ahead. The Indian government has plans to equip the drones with advanced sensors and imaging technology. This will allow Drone Didis to use real-time data to deliver targeted interventions to improve the quality and quantity of farmers’ crops. They will be able to detect diseases and pests, assess soil moisture levels, monitor crop growth, and more.

I’m equally excited to track how the Drone Didi program continues to empower women across India. Every Didi is affiliated with a self-help group, or SHG. The plan is to provide nearly 15,000 drones to SHGs across India by the end of next year.

In the United States, where I live, self-help groups are usually associated with mental health. In India, they’re a form of mutual aid. Each SHG is small—most are around 12 people, although some are as big as 25—and brings together women to support each other socially and financially. They pool their savings, access microloans at lower interest rates, and solve problems in areas like health and education.

The Didis I met with were longtime members of SHGs organized by JEEViKA, an organization in Bihar that works to lift people from rural areas out of poverty. During our time together in Delhi, Kajol told me about how JEEViKA helped her open her own shop three years ago, where she sells seeds and fertilizers. She loves being an entrepreneur, and when she was approached about becoming a Drone Didi, she knew it would do wonders for her business.

Each Didi attends a training program in Hyderabad or Noida, where they are taught how to pilot the drone and apply fertilizer effectively. (I was surprised to hear that learning to fly is apparently easier and takes less time than learning to fertilize!) Other women in their SHGs are trained as drone technicians, ready to repair the machines if any problems arise.

In the less than two years, the Drone Didi program is already transforming the lives of its pilots. Kajol is using the extra income she’s earned to expand her shop offerings and build a warehouse to store her stock. She also plans to send her children to a better school. Sangita’s family couldn’t afford a bicycle before she became a Drone Didi—today, she is the proud owner of an auto rickshaw.

Sumintra hopes that, when people see someone like her flying a huge drone, it changes their perception of what women are capable of. Like many women in her area, she married very young and was expected to stay home with her children. Today, her kids call her “Pilot Mummy” and dream about her flying airplanes one day.

I hope you think of the Didis the next time you hear the buzz of a drone above you at a wedding or a park. It’s remarkable how one piece of technology can reshape what is possible in a community. Kajol told me that people sometimes look at her and say, “She’s flying too high! What will she do next?”

Her response? “This is just the beginning. Wait and see what’s coming.”

I've always thought of myself as a student trying to get to the bottom of things. A good day for me is one where I go to sleep with just a little bit more knowledge than I had when I woke up in the morning. So, when I am deciding how to spend my time these days, I usually ask myself three questions: Will I have fun? Will I make a difference? And will I learn something?

My new Netflix Series, What’s Next? The Future with Bill Gates, is out today. And when I think back on the process of working on it over the last two years, the answer to all three questions is a resounding “yes.”

I had an amazing time working with the super talented director, Morgan Neville. Morgan directed one my favorite documentaries, Best of Enemies, which is about Gore Vidal’s and William Buckley’s debates during the 1968 U.S. presidential election. Morgan also won an Oscar for his terrific film 20 Feet from Stardom.

As you might guess from the title, What’s Next? is a show about the future. I’m very fortunate to get to work on a number of interesting problems. Between fighting to reduce inequities through the Gates Foundation, leading Breakthrough Energy’s work on the climate crisis, and my continued engagement with Microsoft, I have a front seat to some of the biggest challenges facing us today.

I feel extremely grateful to have had the opportunity to work with and learn from some truly incredible people during the making of this show. (I’m hesitant to even use the word “work” because the process was so much fun!) My hope is that people watch What’s Next? and feel like they’re joining me on my learning journey.

Each episode focuses on a different challenge: artificial intelligence, climate change, misinformation, disease eradication, and income inequality. I sat down with some of the big thinkers and innovators who are pushing for progress. Some of them have different ideas than I do about how to tackle these challenges, and I loved getting to hear their perspectives. It was an eye-opening experience.

I got to have conversations on camera with familiar faces like Dr. Anthony Fauci, Open A.I. co-founder Greg Brockman, and the groundbreaking director James Cameron. And I made a lot of new friends as well—including an ingenious malaria researcher from Burkina Faso named Abdoulaye Diabaté, young climate activists who impressed me with their intelligence and passion, and an amazing group of people from across the Bay Area who overcame tremendous adversity in their path from poverty to stability.

There also were dozens of people who participated in the series with standalone interviews, like my friend Bono and the brilliant Mark Cuban—each of whom brings an inspiring and grounded view of the challenges we’re facing. My hope is that, together, we can combat the doomsday narratives that so often surround these issues.

It’s hard to pick which discussion I learned the most from. But three conversations will always stand out in my memory: the ones with Lady Gaga, Senator Bernie Sanders, and my younger daughter, Phoebe.

Going Gaga

I couldn’t help but feel a little nervous.

I was in Palm Desert, CA, preparing to have a filmed conversation with Lady Gaga for our episode about misinformation. Being around famous people doesn’t normally affect me. But I’m a big fan of A Star is Born—especially its music—and I was aware of her reputation as an outsized personality. I couldn’t wait to hear what she had to say.

Luckily, I had nothing to worry about. I was blown away by how thoughtful Gaga was. She made me laugh with the outrageous stories of how she’s been the subject of misinformation in the past—and inspired me with some of the ways she thinks about the topic.

In the early years of her career, one of the most persistent internet rumors about Gaga was that she was actually a man. It became so mainstream that reporters would ask about it during interviews. She refused to confirm or deny it. Instead, Gaga turned it back on the interviewer and asked, “Would it matter if I was?”

On the day of our Netflix conversation, I had been filming earlier with my two sisters, Kristi and Libby. So I asked them to come and watch the conversation between Lady Gaga and me.

Officially, Uganda’s maternal mortality rate is double the global average. But because that number doesn’t count those who give birth at home—in a country where poverty, distance, stigma, and distrust are all barriers to medical care—Eva Nangalo believes the real one may be much higher.

That’s why, as a midwife determined to eliminate these deaths altogether, she’s spent the past 23 years working to make hospital deliveries both more safe and more common.

For Nangalo, this is more than a job. It’s her life’s work, and something she’s felt called to do for as long as she can remember. “I was created to be a midwife, born to be a midwife, trained to be a midwife,” she said. “It’s what is in my DNA. That’s what I am.”

Working the night shift at Nakaseke General Hospital in rural central Uganda and tending to her family’s farm while off the clock, Nangalo is known for sleeping maybe one or two hours, if that, a day. When the power goes out in the middle of a delivery—which happens often—she uses the flashlight on her cellphone to get the job done. She even keeps her hair short rather than style it the way she’d prefer.

In her own words: “I’ve wanted my hair to be like other women. But then I think of the one dollar saving a mother’s life.”

That isn’t theoretical. Nangalo regularly reaches into her own pockets to ensure that expecting mothers have the transportation they need to get to the hospital in the first place—and the food, milk, and medicine they and their babies need to survive not only childbirth but also what comes next. She once tore a piece of her own bedsheet to give to a mother who didn’t have one at home.

It’s no wonder she’s made a name for herself—literally—among the women she’s served, with many choosing to name their daughters after her.

Her advocacy efforts—and their effects—are broad and far-reaching. Understanding the fears and misconceptions that exist in Uganda around healthcare facilities, she uses the radio to reach skeptics and explain the merits of hospital deliveries and the higher risks of fatal infection and bleeding inherent to home births. She helped establish a newborn clinic in Nakaseke, improving the safety of childbirth at the hospital and increasing the number of families served. She even pushed the government to make good on its own policies and open a health facility in every sub-county.

It’s no exaggeration to say that Eva Nangalo is making childbirth in Uganda safer for everyone involved.

“The future looks bright,” one colleague said, “if we have more and more people like Eva.” Fortunately, she’s working to ensure that’s exactly what happens.

Twenty-five years ago, I encountered a question that I have thought about literally every day since: Why do children die?

Before I tell you what drew me to this mystery, I want to acknowledge that child mortality is not an easy subject to talk about. As a parent, I can’t imagine what it would be like to lose a child. It is shocking even to see the words “children” and “die” used in the same sentence.

But I think “why do children die?” is one of the most important questions ever. It is hard to think of a measure of how a society is doing that reveals more than whether it is protecting its children, and especially its most vulnerable children. And the better we understand why children die, the more we can do to save them.

The very good news is that the world has made phenomenal progress in this area over the past several decades. Since 1990, the number of children who die every year has fallen by more than half! If progress on child mortality is a good measure of the state of the world, then—despite the huge global setbacks of the past few years, including COVID-19—the state of the world has improved dramatically. And based on what I know about innovations that are still to come, we can look forward to even more progress in the years ahead.

My introduction to the subject came 25 years ago, when I read a New York Times article about the health problems caused by unsafe drinking water in low- and middle-income countries. I was shocked to learn that every year, 3.1 million people—nearly all of them children—died of diarrhea, often because they had drunk contaminated water. Diarrhea kills 3.1 million children?, I thought. That can’t be true, can it? But it was.

I had to know more. What other major inequities did I not know about?

I read everything about global health that I could find, and I spoke to as many experts as I could. I learned that researchers define child mortality as the death of anyone under the age of 5. They use that age because the first five years are the riskiest time of childhood, when kids are the most vulnerable.

Learning about the history of child mortality helped me put the statistics in context. In 1950, some 20 million children died. In 1990, it was down to 12 million children, even though more babies were being born. By 2000, the number had dropped to fewer than 10 million. By 2019, it was below 5 million. Virtually all of these deaths occur in low- and middle-income countries.

So the next question was, why were so many children dying?

Around 18 percent of the deaths were caused by non-communicable conditions, such as cancer and cardiovascular problems. The large majority—82 percent—of the deaths were caused by communicable diseases, such as diarrhea and malaria, and health problems that their mothers experienced—and exacerbated by risk factors including malnutrition. (This 18:82 ratio still holds true today.)

On one hand, this was heartbreaking. The worst killers were all things that people in rich countries considered just an unpleasant episode (such as diarrhea) or never experienced at all anymore (such as malaria). In other words, although it was obviously true that children were dying because of deadly diseases, that was only part of the explanation. They were also dying because of where they were born.

On the other hand, it was encouraging to learn that such a large share of the deaths was preventable. When I saw the breakdown of diseases, I thought: Here is our road map. This is what the Gates Foundation should be working on. With the right team, partners, and funding, we could help the world move through the list, systematically going after the worst killers. The solutions that already existed could be made more affordable and delivered to people in low-income countries. The ones that didn’t exist could be invented.

Here is the chart as it looks today:

As you can see, pneumonia is the top preventable cause, but the story here is one of real progress. In 2000, it took the lives of more than 1.5 million children, but by 2019, the number was around 670,000—still an awful number, but a reduction of more than 55 percent. The innovation related to pneumonia that’s going on today is so exciting that I made a separate post and video about it.

Diarrhea is another example of progress. In two decades, its death toll has dropped 58 percent. A key reason is the use of low-tech interventions like oral rehydration solution (sugar water, essentially), which replaces lost electrolytes. Governments also ran large-scale sanitation programs to cut down on the spread of bacteria. And scientists developed an affordable rotavirus vaccine, and the world came together to deliver it. Between 2010 and 2020, this vaccine prevented more than 200,000 deaths. By 2030, it will have prevented more than half a million deaths.

Even though the overall number of deaths has gone down by half, the relative positions of the top three killers have not changed. They are the same today as in 1990: neonatal disorders, pneumonia, and diarrheal diseases. As you can see in this graphic, the fourth slot is where there has been a huge shift. In 1990, it was occupied by measles, responsible for half a million deaths. Today, it’s malaria that is in the fourth slot—not because malaria deaths went up (they actually went down), but because measles deaths fell by a whopping 87 percent.

Why? Vaccines. Since 2000, Gavi, the Vaccine Alliance has provided measles vaccines to more than 500 million children—half a billion!—through routine immunization and special vaccination campaigns. (This is just one example of the magic of vaccines—although unfortunately vaccination rates have dropped because of the pandemic and other factors.) And malaria may not be #4 on that list for long, thanks to innovations like malaria vaccines, improved insecticide-treated bed nets, and sugar baits.

Many groups deserve credit for the decades of progress I’ve described in this post. Countries with high disease burdens have launched massive vaccination campaigns, strengthened their health systems, and shared best practices with each other. Wealthy countries generously give aid that supports these efforts. Pharmaceutical companies have contributed technical expertise and made products affordable for low- and middle-income countries. Foundations including the Gates Foundation have stepped up with additional funding for innovative ideas. (At the foundation, we have staff and partners dedicated to each slice of the pie you see above.)

Although it’s still true that too many children do not live to see their fifth birthday, the world is moving in the right direction. If everyone keeps doing their part, we can move even faster and save even more lives. Because of COVID and other setbacks, the United Nations’ goal to cut childhood deaths in half again to below 3 million by 2030 will be missed, but it can still be achieved the following decade.

At a time when war and pandemic are in the news every day, it is important to look for reasons to be hopeful. The world’s opportunity—and ability—to save children’s lives is surely one of those reasons.

Of all the things I thought would help fight malaria, 100-year-old mosquitoes would not have been high on the list. Then I learned about the work of Dr. Mara Lawniczak.

An evolutionary geneticist at the Wellcome Sanger Institute in the United Kingdom, Mara has spent much of her career trying to understand how the genomes of various mosquito species have changed in response to humans’ attempts to kill them. When, where, and how fast has it happened? What does that say about how they might evolve in the future?

In recent years, genetics has become an increasingly important tool for fighting malaria. Because mosquitoes breed so fast (a female can lay thousands of eggs in her lifespan of a couple of weeks), they evolve rapidly, at least compared to humans. By studying their genes, researchers are able to understand things like how they develop resistance to insecticides, crucial information that helps humans stay one step ahead.

After a few years of studying mosquitoes’ genomes, Mara had grown frustrated by the fact that the only insects available for study were ones that had been captured recently. Without DNA from their ancestors, there was no way to know how their genomes had responded to decades of human attacks. “We were often saying, ‘If only we could look into the past,’” Mara says. “And then it suddenly struck me: I'm sure there are historical collections of mosquitoes around.”

She was right. The Natural History Museum in London has a collection of 34 million insects from all over the world, carefully collected and preserved. Among the collection is a large sample of mosquitoes dating from 1936, when a British entomologist named H.S. Leeson spent a year in East Africa capturing and cataloguing the insects in the hope of learning more about malaria. Leeson didn’t know it at the time—DNA wouldn’t be discovered until the 1950s—but his collection of mosquitoes would become a vast source of genetic material that someone like Mara could study.

Mara reached out to the museum’s curators. They wanted to help, but there was a problem: Extracting DNA from the insects would require Mara to grind them up. Since the museum’s mission is to preserve its collection for future generations, they couldn’t let her do that.

So Mara and her colleagues invented a way around the problem. Working with the museum’s team, they developed a novel way to extract DNA from mosquitoes without damaging the specimen.

They affectionately call this work Project Neandersquito. It’s not because the mosquitoes date from the time of Neanderthals, some 40,000 years ago—this isn’t Jurassic Park, where they extract dinosaur DNA from a prehistoric mosquito trapped in amber. It’s because the mosquitoes they’re studying are 1,000 or 2,000 generations removed from modern ones, just as Neanderthals are more than 1,000 generations removed from modern humans.

Mara’s team has made some surprising finds. For example, because mosquitoes started developing resistance to the insecticide DDT in the 1950s, they expected to see genetic mutations for resistance appearing around the same time. But they didn’t. “We still don't see them even as late as the 1980s,” she says. “So the mosquitoes were somehow making themselves resistant to DDT in ways that we still don't really understand.”

They also hope to get insight into what's coming. “How fast can mosquitoes evolve? And as we throw new control initiatives at them, how quickly are they going to get around them?” Other labs are now using the process devised by the Lawniczak Group to do their own research.

Project Neandersquito is just one of the ways Mara and her team are using genomics to advance the fight against malaria. A different project, the Malaria Cell Atlas, is providing new genetic data that could inform the effort to make better malaria drugs and vaccines. Another project is designed to make it easier and cheaper to identify a mosquito’s species using its DNA—it’s surprisingly hard to do just by looking—as well as whether it’s carrying the parasite that causes malaria, and even which species of the parasite it has. Ultimately, the project’s goal is to help governments get data that will help them get the most out of their anti-malaria efforts.

Mara would be the first to say that these are just a few examples of the tools the world needs to eradicate malaria. It’s going to take global cooperation from governments, the private sector, and academia. And now we can add natural history museums to the list.

Each year, I love sharing stories from around the world about the incredible work being done to fight malaria. Sometimes, though, those stories are best told firsthand. That’s why I invited Professor Charles Wondji—a malaria researcher, mosquito geneticist, and executive director of the Centre for Research in Infectious Diseases in Cameroon—to share his.

Dr. Magellan Tchouakui, Cameroon, Medical Entomology and Vector Control

Dr. Tchouakui is an expert in assessing the impacts of insecticides on major African malaria vectors’ abilities to survive and reproduce. He’s passionate about putting that research to use, and leads the testing of many companies’ novel insecticide formulations to improve bed nets and indoor-residual sprays.

Dr. Mersimine Kouamo, Cameroon, Functional Genomics

Dr. Kouamo employs tools such as transgenesis to “knock down” certain genes in mosquitoes, allowing her to study the genes’ functions and understand which ones enable the mosquitoes to withstand insecticide exposure. She is also a role model to younger female scientists.

Dr. Leon Mugenzi, Rwanda, Molecular Genetics of Vectors

Dr. Mugenzi’s interest is in providing and improving the tools used to control the spread of malaria. During his PhD work at CRID, he designed the first DNA-based diagnostic tool to detect metabolic resistance in mosquitoes to insecticides, which helps prolong the effectiveness of bed nets.

The most dangerous foe U.S. soldiers may have ever encountered is the mosquito, which has caused more casualties than bombs or bullets during the nation’s conflicts.

One of the first military expenditures by the Continental Congress was $300 for quinine to protect General George Washington’s troops from malaria. During the Civil War, there were over a million cases of malaria in Union troops alone. In World War II, there were nearly 700,000 cases of malaria. In Vietnam, 50,000 cases. And more recently, of all the American soldiers deployed in Afghanistan, one out of every 20 of them battled malaria.

Finding ways to protect soldiers from the mosquito—the world’s deadliest animal—is a top priority at the U.S. Department of Defense’s Walter Reed Army Institute of Research (WRAIR).

I expect most people have never heard about WRAIR—or, if they have, they may be confusing it with the more familiar but separate institution, the Walter Reed National Military Medical Center, where U.S. presidents visit wounded troops and go for medical treatment.

It’s too bad more people don’t know about the work being done at WRAIR. Since its founding in 1893, WRAIR has been a global research leader into new malaria drugs, mosquito control, and more recently, vaccines, to protect people from mosquito-borne diseases. This research benefits the lives of not only American soldiers, but also billions of people living in areas where mosquito-borne diseases are a threat. That’s why our foundation collaborates with WRAIR on a range of research projects in malaria and other diseases that endanger the lives of people living in some of the world’s poorest areas.

Here’s one of many incredible facts that speak to WRAIR prominence in malaria research: WRAIR has contributed to the discovery and development of all FDA-approved malaria drugs, including primaquine, mefloquine, atovaquone/proguanil (Malarone), tafenoquine, and doxycycline. If you’ve ever traveled to an area where malaria is prevalent you’ve probably been prescribed one of these drugs for protection. And because of the spread of malaria drug resistance, WRAIR continues to explore new drugs to stay one step ahead of this threat.

WRAIR, in partnership with the Smithsonian Institute, also manages the world’s largest mosquito collection, which currently has more than 1.7 million specimens. Some of the oldest were collected by Walter Reed, the Army major who helped discover that yellow fever is transmitted by mosquitoes. WRAIR is named in his honor.

This large mosquito collection allows WRAIR researchers to “know their enemy,” by giving them a deep understanding of the huge variety of mosquito species that populate the globe so they can mount the most effective defenses against them.

The first line of defense for soldiers is their clothing and WRAIR has developed uniforms treated with insecticides to protect them. Then, there are mosquito nets and various repellents, including ones that double as camouflage paint.

Highly effective vaccines against malaria and other mosquito-borne disease are also a priority at WRAIR. WRAIR developed the first-ever malaria vaccine in conjunction with GlaxoSmithKline. Researchers at WRAIR also led the development of a Zika vaccine.

One of the most surprising and important areas of research at WRAIR are the human malaria infection challenge trials. As part of this program, WRAIR recruits volunteers who agree to be bitten by malaria-infected mosquitoes, exposing themselves to a curable form of the disease to test the effectiveness of various interventions. This might sound scary, but the trials are extremely safe. The volunteers are carefully monitored and are quickly cured before they become too ill. In the last 30 years, WRAIR has performed over 100 trials on over 2,200 volunteers. Thanks to this research, WRAIR has greatly accelerated the development of experimental vaccines and malaria drugs.

What’s most exciting at WRAIR is the research that will help us all prepare for the threats of the future, including climate change, which will increase the spread of mosquito-borne diseases.

As Col. Brian Evans, WRAIR’s chief entomologist, says, “The challenge is always evolving and the role of WRAIR is to keep up with that, to stay ahead of the game.”

Thanks to their incredible work for more than 125 years, WRAIR has done just that.

Inside a two-story brick building in Medellín, Colombia, scientists work long hours in muggy labs breeding millions and millions of mosquitoes. They tend to the insects’ every need as they grow from larvae to pupae to adults, keeping the temperature just right and feeding them generous helpings of fishmeal, sugar, and, of course, blood.

Then, they release them across the country to breed with wild mosquitoes that can carry dengue and other viruses threatening to sicken and kill the population of Colombia.

This might sound the beginnings of a Hollywood writer’s horror film plot.

But it’s not.

This factory is real.

And the mosquitoes being released don’t terrorize the local population. Far from it. They’re actually helping to save and improve millions of lives.

Here’s how they do it: The mosquitoes being produced in this factory carry bacteria called Wolbachia that block them from transmitting dengue and other viruses, such as Zika, chikungunya and yellow fever, to humans. By releasing them to reproduce with wild mosquitoes, they spread the bacteria, reducing virus transmission and protecting millions of people from illnesses.

I’ve written before about these amazing Wolbachia mosquitoes, including last year when a new study showed how effective they could be in preventing diseases. The randomized controlled trial conducted in Yogyakarta, Indonesia, found that Wolbachia-carrying mosquitoes reduced the number of dengue cases in the city by 77 percent and dengue hospitalizations by 86 percent. In a new study in Medellín, dengue cases have declined by 89 percent since Wolbachia mosquitoes started being released in 2015.

These results are a huge breakthrough, offering proof that this new technology will protect entire cities and countries against the threat of mosquito-borne diseases. The World Mosquito Program, which is leading the Wolbachia effort, is now releasing these mosquitoes in 11 countries: Brazil, Colombia, Mexico, Indonesia, Sri Lanka, Vietnam, Australia, Fiji, Kiribati, New Caledonia, and Vanuatu.

And what’s remarkable about the Wolbachia mosquitoes is that once enough of them are released to offer disease protection, it’s a solution that’s self-sustaining. Over time, families will be spared the heartbreak of losing loved ones and communities won’t need to spend money on prevention and treatment for these mosquito-borne diseases, freeing up funds for other health priorities.

The World Mosquito Program aims to spread Wolbachia among Aedes aegypti mosquitoes, a tropical mosquito that is a host for dengue, yellow fever, and other viruses. (Malaria is spread through a parasite carried by the Anopheles mosquito and is not a focus of the Wolbachia effort.) With climate change, there is an urgency to the World Mosquito Program’s work. As global temperatures rise, Aedes aegypti mosquitoes, are finding more regions of the world habitable, increasing the spread of these diseases. The biggest risk is posed by dengue, which infects more than 400 million people each year and kills 20,000.

The demand for these lifesaving mosquitoes continues to grow and that means the World Mosquito Program needs to produce hundreds of millions of Wolbachia mosquitoes. That brings us back to the factory in Medellín, which is currently the world’s largest mosquito breeding facility in the world, producing more than 30 million mosquitoes per week. Other World Mosquito Program sites around the world are also breeding Wolbachia mosquitoes, but Colombia’s is currently the largest.

Until now, killing or repelling mosquitoes with insecticides, bed nets, and traps has been the priority, not mass producing them. As difficult as it is to kill mosquitoes, raising them by the millions may be even harder. Mosquitoes must be bred, fed, and housed under ideal conditions for them to grow and reproduce. The factory in Medellín has been perfecting the process and improving its efficiency so they can breed and release Wolbachia mosquitoes on a large scale.

The centerpiece of the mosquito factory is a colony of Wolbachia mosquitoes, called the brood stock, from which all future populations of Wolbachia mosquito offspring are bred. The brood stock offspring are then raised to create millions of eggs, which hatch when put in water and become larvae. Fed with fish meal, the larvae grow to become pupae, which then become adults. To thrive, adults need sugar (check out this story about how researchers in Zambia are exploiting mosquito’s craving for sugar to create a new bait that will control the spread of malaria) and blood, which the team sources from expired stocks at blood banks. 

Once the factory has bred millions of eggs and adult mosquitoes, they are ready to be released. The eggs are packaged in small gelatin capsules, each containing 300 eggs, which are given to residents to drop in water to hatch. The advantage of egg releases like this is that the eggs can easily be transported long distances and they can be hatched as needed.  The factory also releases adult mosquitoes by the thousands from the back of motorcycles roving the city. The World Mosquito team is also experimenting with releases from drones. The adult releases allow the Wolbachia mosquitoes to immediately begin mating with the wild mosquito population and spreading the virus-blocking bacteria.

It’s exciting to see how far the World Mosquito Program has come. Years ago, the idea of releasing mosquitoes as an ally in the fight against diseases struck many people as crazy. But support for this innovative solution has caught on in communities around the world. These amazing mosquitoes are taking flight and saving lives.

Everyone knows mosquitoes have a taste for blood, but did you know they have an even bigger sweet tooth?

Mosquitoes love sugar.

Just as humans are drawn to the sweet smell of a chocolate shop or bakery, mosquitoes find the smell of sugar irresistible.

All mosquitoes need sugar to survive. Female mosquitoes consume blood to lay eggs, but both male and female mosquitoes require sugar for energy. In fact, even though mosquitoes buzzing in your ears may appear single-minded about biting you, they need sugar more often than they need blood.

Exploiting this craving, researchers have developed a lethal new tool to kill mosquitoes and protect people living in areas at high risk for malaria and other mosquito-borne diseases.

Here’s how it works: In nature, mosquitoes get sugar from flower nectar and plants. But scientists have developed a tempting bait that lures mosquitoes with a highly attractive fruit scent. When they land on it to get their sugar fix, the mosquitoes begin feasting on a sweet meal laced with insecticide. Not long after, they drop dead, reducing mosquito populations and, researchers hope, the spread of malaria in the communities where the traps are used.

While other insects, like bees and butterflies, may also be drawn to the bait’s sweet scent, the bait is just lethal for mosquitoes. A protective membrane, only accessible to mosquitoes, covers the bait and prevents other insects from feasting on the deadly meal inside.

This new mosquito control tool, called Attractive Targeted Sugar Baits or ATSBs, developed by Westham Co., is simple to use, affordable, and has the potential to be a game changer in the effort to eradicate malaria.

And it couldn’t arrive soon enough.

Over the past two decades, the world has dramatically reduced the global burden of malaria, preventing 1.7 billion cases and saving 10.6 million lives. This progress has been attributed, in large part, to the widescale use of long-lasting insecticide-treated bed nets, which protect people from bites while they sleep, and indoor residual spraying, which kills mosquitoes that land on insecticide-treated walls and ceilings in homes.

As effective as these tools have been, both mosquitoes and the malaria parasite are constantly evolving, sometimes making these interventions less effective. We’ve seen this again and again with resistance to insecticides and malaria drugs. And that’s why it’s critical that the world continues to innovate with new ways to prevent the spread of malaria.

In response to the widespread use of bed nets and indoor insecticide spraying, mosquitoes have changed their behaviors, according to some researchers. In some areas, instead of seeking their blood meals only inside homes after bedtime, malaria-carrying mosquitoes are now biting outside homes, and earlier in the evening, when people will often cook and socialize.

And this is how the sugar baits fit in.

By attracting mosquitoes outside, sugar baits offer a highly effective mosquito control tool for households. About the size of a sheet of notebook paper, sugar baits can be easily installed with a hammer and a nail. Two baits hung on the adjacent outside walls of a home are enough to offer months of protection.

In studies conducted in Mali in 2016 and 2017 researchers found that the sugar baits dramatically reduced mosquito populations and malaria cases in the communities where they were used.

A more recent modeling analysis predicted that sugar baits, when used to complement long-lasting insecticide-treated bed nets and indoor spraying, could reduce malaria cases by 30 percent in areas with high malaria burdens.

In 2020, there were an estimated 241 million malaria cases. A 30 percent reduction in malaria cases would be a huge breakthrough and save many lives.

That’s why our foundation has been supporting the development of sugar baits, including sponsoring a large-scale field trial currently underway in Kenya, Mali, and Zambia. So far, the results have confirmed the effectiveness of the bait stations.

If all goes well with the trials, sugar baits could be available for widespread use as soon as next year.

No need to sugarcoat it. For the millions of people at risk of malaria around the world, that would be welcome news.

Have you ever visited a place you haven’t been in a while, and it somehow manages to feel both new and familiar? That’s how I feel every time I go back to Nigeria.

It was amazing to return to Lagos and Abuja this week. I’ve been fortunate to spend a lot of time in Nigeria over the last two-plus decades, but it’s been nearly five years since my last visit due to the pandemic. Nigeria—and especially Lagos—is one of the most dynamic, vibrant places in the world, and I am always blown away by how much it's changed. At the same time, I loved getting to catch up with old friends and reconnect in person with longtime partners. (Remote meetings are great, but it’s nice to meet face-to-face on occasion.)

This week also marked my first-ever trip to Niger. Our foundation has been working with talented Nigeriens for years to help ensure children's health and prevent the spread of polio, and it was exciting to see the country for myself and talk about the future of that work.

It was a great week. These were some of my favorite moments:

Every Christmas when I was a kid, my parents would send out a card with an update on what the family was up to. Dad’s law firm is growing, Mom’s volunteer work is going strong, the girls are doing well in school, Bill is a handful.

Some people think it is corny, but I like the tradition. These days, at the end of each year, I still enjoy taking stock of my work and personal life. What was I excited about? What could I have done better?

I thought I would share a few of these thoughts as 2018 concludes.

One thing that occurs to me is that the questions I am asking myself at age 63 are very different from the ones I would have asked when I was in my 20s.

Back then, an end-of-year assessment would amount to just one question: Is Microsoft software making the personal-computing dream come true?

Today of course I still assess the quality of my work. But I also ask myself a whole other set of questions about my life. Did I devote enough time to my family? Did I learn enough new things? Did I develop new friendships and deepen old ones? These would have been laughable to me when I was 25, but as I get older, they are much more meaningful.

Melinda has helped broaden my thinking on this point. So has Warren Buffett, who says his measure of success is, “Do the people you care about love you back?” I think that is about as good a metric as you will find.

It may sound grand, but I think the world is slowly going through a similar transition to a broader understanding of well-being. For most of human history, we have been focused on living longer by fighting disease and trying to grow enough food for everyone. As a result, life spans have gone up dramatically. Technology has played a key role in that through vaccines, medicines, and improved sanitation.

We still need a lot of innovation to solve problems like malaria or obesity, but we are also going to be focusing more on improving the quality of life. I think this will be the thrust of many big breakthroughs of the future. For example, software will be able to notice when you’re feeling down, connect you with your friends, give you personalized tips for sleeping and eating better, and help you use your time more efficiently.

There are not the same clear measures of these things as there are for diseases, and there may never be. But there is nascent work in this field and I think it is going to accelerate.

As I look back on the year, I am also thinking about the specific areas I work on. Some of this is done through our foundation but a lot of it (such as my work on energy and Alzheimer’s work) is not. What connects it all is my belief that innovation can save lives and improve everyone’s well-being. A lot of people underestimate just how much innovation will make life better.

Here are a few updates on what’s going well and what isn’t with innovation in some areas where I work.

Alzheimer’s disease

I saw two positive trends in Alzheimer’s research in 2018.

One is that researchers focused on a new set of ideas about how to stop Alzheimer’s.

The first generation of theories, which dominated the field for years, emphasized two proteins called amyloid and tau. These proteins cause plaques and tangles in the brain, clogging up and killing brain cells. The idea was to stop the plaques and tangles from forming. I hope these approaches pay off, but we have not seen much evidence that they will.

In the past year, researchers have doubled down on a second generation of hypotheses. One theory is that a patient’s brain cells break down because their energy producers (called mitochondria) wear out. Another is that brain cells break down because part of the immune system gets overactivated and attacks them.

This is a great example of how improving our understanding of biology will reduce both medical costs and human suffering.

The other trend this year is that the Alzheimer’s community focused on getting more and better access to data. We’re working with researchers to make it easier for them to share information from their studies broadly so that we can better understand questions like how the disease progresses.

Over the past few years, the U.S. government has dramatically stepped up funding for Alzheimer’s research, from $400 million a year to over $2 billion a year. There is also a big push to create better diagnostics.

The only problem where I don’t yet see a clear path forward yet is how to develop more efficient ways to recruit patients for clinical trials. Without a simple and reliable diagnostic for Alzheimer’s, it’s hard to find eligible people early enough in the disease’s progression who can participate in trials. It can take years to enroll enough patients. If we could find a way to pre-screen participants, we could start new trials more quickly.

But there is so much momentum in other areas—scientific tools, better diagnostics, improved access to data—that as long as we can solve the recruitment problem, I am confident that we will make substantial progress in the next decade or two.

Polio

I thought we would be closer to eradicating polio today than we are. Unfortunately, there were more cases in 2018 than in 2017 (29 versus 22).

I underestimated how hard it would be to vaccinate children in places where there’s political violence and war. Families move around to escape fighting, which makes it hard to keep track of children and make sure they get all the doses of the vaccine. Or sewage systems get destroyed, allowing the virus to spread as children come into contact with an infected person’s excrement.

This is a key reason why Afghanistan and Pakistan have never been free of polio—in fact they are the only two countries that have never been free of polio.

I spend a lot of time on polio, part of it talking to the funders to make sure they continue their commitment even though eradication is taking longer than any of us would like. I remind them of the huge benefits of success, and the risk that the disease will return in a big way if we don’t finish the job.

I also remind them what a difference innovation is making. We’re now able to test sewage samples to track the virus and find the source before an outbreak starts. And the global health community is finding creative ways to work in war zones, having stopped outbreaks in Syria and Somalia in recent years.

Finally, I am hopeful about a new oral vaccine being tested in Belgium and Panama. The results should be out in 2019, and if this one proves effective, it would overcome some of the problems with previous oral vaccines when they’re used in places where few children are immunized. The new vaccine could be in use as soon as 2020.

Despite all the challenges, I am still optimistic that we can eradicate polio soon.

Energy

Global emissions of greenhouse gases went up in 2018. For me, that just reinforces the fact that the only way to prevent the worst climate-change scenarios is to get some breakthroughs in clean energy.

Some people think we have all the tools we need, and that driving down the cost of renewables like solar and wind solves the problem. I am glad to see solar and wind getting cheaper and we should be deploying them wherever it makes sense.

But solar and wind are intermittent sources of energy, and we are unlikely to have super-cheap batteries anytime soon that would allow us to store sufficient energy for when the sun isn’t shining or the wind isn’t blowing. Besides, electricity accounts for only 25% of all emissions. We need to solve the other 75% too.

This year Breakthrough Energy Ventures, the clean-energy investment fund I’m involved with, announced the first companies we’re putting money into. You can see the list at http://www.b-t.energy/ventures/our-investment-portfolio/. We are looking at all the major drivers of climate change. The companies we chose are run by brilliant people and show a lot of promise for taking innovative clean-energy ideas out of the lab and getting them to market.

Next year I will speak out more about how the U.S. needs to regain its leading role in nuclear power research. (This is unrelated to my work with the foundation.)

Nuclear is ideal for dealing with climate change, because it is the only carbon-free, scalable energy source that’s available 24 hours a day. The problems with today’s reactors, such as the risk of accidents, can be solved through innovation.

The United States is uniquely suited to create these advances with its world-class scientists, entrepreneurs, and investment capital.

Unfortunately, America is no longer the global leader on nuclear energy that it was 50 years ago. To regain this position, it will need to commit new funding, update regulations, and show investors that it’s serious.

There are several promising ideas in advanced nuclear that should be explored if we get over these obstacles. TerraPower, the company I started 10 years ago, uses an approach called a traveling wave reactor that is safe, prevents proliferation, and produces very little waste. We had hoped to build a pilot project in China, but recent policy changes here in the U.S. have made that unlikely. We may be able to build it in the United States if the funding and regulatory changes that I mentioned earlier happen.

The world needs to be working on lots of solutions to stop climate change. Advanced nuclear is one, and I hope to persuade U.S. leaders to get into the game.

The next epidemic

In 1918, the Spanish flu killed 50 million people worldwide. It still ranks as one of the deadliest natural disasters ever.

I had hoped that hitting the 100^th anniversary of this epidemic would spark a lot of discussion about whether we’re ready for the next global epidemic. Unfortunately, it didn’t, and we still are not ready.

People rightly worry about dangers like terrorism and climate change (and, more remotely, an asteroid hitting the Earth). But if anything is going to kill tens of millions of people in a short time, it will probably be a global epidemic. And the disease would most likely be a form of the flu, because the flu virus spreads easily through the air. Today a flu as contagious and lethal as the 1918 one would kill nearly 33 million people in just six months.

I have been studying this for several years. To be prepared, we need a plan for national governments to work together. We need to think through how to handle quarantines, make sure supply chains will reach affected areas, decide how to involve the military, and so on. There was not much progress on these questions in 2018.

The good news is that there has been progress toward a vaccine that would protect you from every strain of the flu. This year I visited the U.S. National Institutes of Health in Maryland and got an update from some of the people leading this work.

The challenges of making a universal flu vaccine are fascinating. All strains of the virus have certain structures in common. If you’ve never been exposed to the flu, it’s possible to make a vaccine that teaches your immune system to look for those structures and attack them. But once you’ve had the flu, your body obsesses over the strain that got you sick. That makes it really hard to get your immune system to look for the common structures.

So it is clear how we could make a universal vaccine that would protect anyone (such as the very young) who has never been exposed to the flu before. But for anyone who has already had the virus, it is a lot harder. The problem is a long way from being solved, but new research money is coming in and more scientists are working on it.

To make the most of these scientific efforts (some of which our foundation is funding), the world needs to develop a global system for monitoring and responding to epidemics. That is a political matter that requires international cooperation among government leaders. This issue deserves a lot more focus.

Gene editing

Gene editing made the news in November when a Chinese scientist announced that he had altered the genes of two baby girls when they were embryos. What is unprecedented about his work is that he edited their germline cells, meaning the changes will be passed down to their children. (The other, less controversial type of gene editing involves somatic cells, which aren’t inherited by future generations.)

I agree with those who say this scientist went too far. But something good can come from his work if it encourages more people to learn and talk about gene editing. This might be the most important public debate we haven’t been having widely enough.

The ethical questions are enormous. Gene editing is generating a ton of optimism for treating and curing diseases, including some that our foundation works on (though we fund work on altering crops and insects, not humans). But the technology could make inequity worse, especially if it is available only for wealthy people.

I am surprised that these issues haven’t generated more attention from the general public. Today, artificial intelligence is the subject of vigorous debate. Gene editing deserves at least as much of the spotlight as AI.

I encourage you to read up on it whenever you have a chance. Keep an eye out for articles in your news feed. If you are willing to read a whole book, The Gene by Siddhartha Mukherjee is very well done. This story is one to follow, because big breakthroughs—some good, some worrisome—are coming.

Looking ahead

I am making a resolution for 2019.

Although I have never been one for New Year’s resolutions, I have always been committed to setting clear goals and making plans to achieve them. As I get older, these two things look more and more like the same exercise. So I am making a resolution for 2019. I am committing to learn and think about two key areas where technology has the potential to make an enormous impact on the quality of our lives, but also raises complex ethical and social considerations.

One is the balance between privacy and innovation. How can we use data to gain insights into education (like which schools do the best job of teaching low-income students) or health (like which doctors provide the best care for a reasonable price) while protecting people’s privacy?

The other is the use of technology in education. How much can software improve students’ learning? For years we have been hearing overheated claims about the huge impact that technology would have on education. People have been right to be skeptical. But I think things are finally coming together in a way that will deliver on the promises.

I will be posting updates on these and other issues on the Gates Notes.

In the meantime, Melinda and I are working on our next Annual Letter. The theme is a surprise, though it is safe to say we’ll be sharing some positive trends that make us optimistic about the future. We’ll send the letter out in February.

I hope you have a happy and healthy start to 2019.

I recently visited a remarkable farm in Carnation, Washington, just 25 miles from downtown Seattle.

At first glance, Dancing Crow Farm looks like any other farm. There are rows of crops and, at least when I was there, the field was dusty. There were farm implements and freshly picked peppers piled up under a lean-to. But if you talk to Sean Stratman—the man responsible for this plot—it quickly becomes clear what makes his farm so special: Sean knows more about his land than almost any other farmer on earth.

Dancing Crow Farm is the pilot site for FarmBeats, an amazing new project that hopes to make farmers more productive by arming them with data. When most people think of groundbreaking digital technology, they don’t picture soil sensors. But a farmer who knows the temperature, pH, and moisture level of his soil can make all sorts of informed decisions that save money and boost yield.

For example, fertilizer works better when it’s applied to moist soil. But how do you know when to fertilize? Soil that feels dry is often still damp below the surface. You’ll end up fertilizing more often than necessary if you go by touch alone. But if you know exactly how much moisture is in your soil at any given moment, you can fertilize only when you need to. You use less and save money.

The problem is that most existing digital platforms that provide this kind of information are expensive. Sensors can cost hundreds of dollars each, and each one only covers 10 meters. The cost is so prohibitive that only the very richest farmers can afford them.

A team of researchers at Microsoft—led by researcher Ranveer Chandra, who I talk to in the video above—wants to change that. In FarmBeats, they’ve developed a series of innovations that might one day put data in the hands of even the poorest farmers.

The main innovation is in how FarmBeats sensors transmit data. Most farms have poor or no access to the Internet. In the United States, 20 percent of people living in rural areas don’t have access to even the slowest broadband speeds. Most farm data systems require expensive transmitters to connect, but FarmBeats relies on a clever workaround: it uses TV white space.

White spaces are unused TV broadcast spectrum. If you’ve ever watched an old TV, you’ve seen white spaces before. They’re the “snow” you’ll sometimes see while flipping through channels. These gaps in spectrum are plentiful in the remote areas where most farms are located, so data can be sent over them the same way that data gets transmitted via broadband.

Here’s how FarmBeats works: The whole system is powered by solar panels. You place a small number of sensors—one every couple hundred meters, instead of 10 meters—in the ground. You then attach your smart phone with the camera facing down to either a drone (if you have money to spare) or a helium balloon (if you don’t).

You walk around the fields with the camera, creating an aerial map of the farm. Data from both the sensors and the phone are transmitted via TV white space to your computer, where an edge device stitches everything together into a data map.

The data generated by FarmBeats has been a game changer for Sean and Dancing Crow Farm. He can use up to 30 percent less water for irrigation and 44 percent less lime to control soil pH. Information on soil temperature and moisture levels has helped him better time the planting of seeds, so he gets a more productive harvest. Because Dancing Crow Farm is located next to a river, flooding is a problem. FarmBeats’ aerial imaging capabilities precisely document flooding patterns, so he’s able to better plan what he plants where. The system even helped Sean identify parts of the farms where inadequate drainage was affecting the quality of beans.

It’ll be at least a year before every component of FarmBeats is available to the public—and even longer before the cost comes down enough for broad adoption (the current version is much cheaper than other farm data systems but still too expensive for poor farmers to afford). But I’m hopeful that one day this technology could be available to every farmer everywhere, including the most remote parts of Africa.

Even as they continue working on the current version, the FarmBeats team is already working on the next generation of their technology. They just released a paper demonstrating for the first time that Wi-Fi signals can be used to collect soil data. Using only their smart phones and super cheap RFID tags buried in the ground, any farmer could get important information about their land—no special, high tech equipment required.

The Wi-Fi technology is still theoretical, but I’m glad brilliant minds are thinking about how we can help the poorest farmers gather data and increase yield. Even small gains in productivity could mean the difference between affording to send your kids to school or not. And for farmers who rely on the food they grow to feed their family—where the size of your harvest is a matter of life or death—FarmBeats could be a literal lifesaver.

More than three-quarters of the world’s poor rely on agriculture to earn a living. If we’re going to win the fight against poverty, we must help farmers—and I believe that FarmBeats could be a powerful tool.

One of my favorite websites is OurWorldInData.org. Based at the University of Oxford, it uses statistics—on everything from health and population growth to war, the environment, and energy—to give you phenomenal insight into how living conditions are changing around the world. I asked its founder, Oxford economist Max Roser, to share three facts from the site that everyone should know. Here’s what Max had to say. – Bill Gates

In the past few years, it has become easy to find many of the important statistics on global development with a quick online search. And since it is now so easy to find the information you need, many argue that it doesn’t make sense to actually remember these statistics. ‘Just look them up when you need them!’ they say.

I disagree with this. Yes, for some details, it makes sense to just search for them when you need them. But for the large global developments, it is important to know some basic statistics that describe living conditions currently and the direction of change that we have seen over the past few decades. Knowing the facts on global changes gives you the context for the daily news and allows you to make sense of new information that you learn. And it must be the basis for political debate, so that we can discuss what we should and shouldn’t do as a society.

And so I compiled a short list of three facts about global living conditions that I want to remember. Each of them describes the current situation and the direction of change.

Fact #1: Since 1960, child deaths have plummeted from 20 million a year to 6 million a year.

Imagine how awful it must be to see your child die.

Then consider that every minute this happens to about 11 parents. This is the number of children, younger than five years of age, who die—on average—every single minute. Eleven deaths every minute for 24 hours add up to 15,500 deaths per day, or 5.6 million deaths per year.

Do we just have to accept that? Is that just how the world is?

Clearly no. We are very much able to drive positive change. Look at the chart below. The same UN data that shows us that 5.6 million are dying today also shows us that in the 1950s and 60s the world saw around 20 million children dying every year.

One key reason why we struggle to see progress in the world today is that we do not know how very bad the past was.

Both are true at the same time: The world is much better than in the past and it is still awful.

To bring this to mind I need to know both statistics: When someone says we can sit back and relax because the world is in a much better place, I point out that 11 children are still dying every minute. We cannot accept the world as it is today. And when I feel hopeless in the face of this tragedy, I remember that we reduced annual child deaths from 20 million to 5.6 million in the last fifty years.

So I am remembering the current extent of child mortality and the direction of change that we have seen: The number of child deaths is falling; there were 3.5-times as many child deaths 50 years ago. But child deaths are still extremely common; 11 children are dying every minute.

Fact #2: Since 1960, the fertility rate has fallen by half.

The chart below shows the key statistic to understand about world population growth: the global fertility rate—the average number of children per woman in the world. When the fertility rate is close to 2 children per woman, so that every couple is on average replaced by about two children, population growth is slow. But until the late 1960s, each woman had on average more than 5 children, and at such high fertility rates, population growth is fast. At that time the world population increased by 2 percent every year.

The availability of contraceptives allows parents to have only as many children as they want. And that number changes as people’s income goes up. From decades of demographic research, we know that women decide to have fewer children as they get access to better education and better opportunities in the job market. We also know that when child mortality falls, so that families do not need to fear that their children will die, they consequently decide to have fewer children in the first place.

Improvements in conditions for women and the health of children have driven a rapid reduction in fertility rates across the world. In fact, the global fertility rate has halved in the last 50 years, from more than 5 children per woman to fewer than 2.5 children. The world population growth rate has also halved in the last 50 years and is just above 1 percent.

The statistic that I remember on population growth is the one that tells me that rapid population growth is coming to an end in this century. In the last 50 years the global fertility rate has fallen from 5 children per woman to less than 2.5 children per woman. In fifty years the fertility rate has halved.

Fact #3: 137,000 people escaped extreme poverty every day between 1990 and 2015.

Living in poverty means that many of the most essential things in life are out of reach. People in poverty tend to lack decent shelter and basic healthcare, and they often struggle to afford adequate food supplies.

People are considered to live in ‘extreme poverty’ if they have to get by on less than 1.90 international-dollars per day, which is a currency that corrects for price differences between countries and inflation.

In this definition of poverty, the term extreme poverty is clearly appropriate: this is a very low poverty line.

When you ask people whether the world is making progress against extreme poverty, the majority of us believe things are getting worse—that the number of people in extreme poverty in the world is rising.

The opposite is true. Both the number and the share of people in extreme poverty is falling:

In 1990, 1.86 billion people were living on less than 1.90 international-$ per day—more than every third person in the world. Twenty-five years later, the number of people living in extreme poverty has more than halved to 706 million, every tenth person.

This is a very large transformation. It means that, on average, every day for the past 25 years 137,000 fewer people were living in extreme poverty than the day before. On every day in the last 25 years there could have been a newspaper headline reading, “The number of people in extreme poverty fell by 137,000 since yesterday.”

This is the statistic I remember: Today every 10th person is living in extreme poverty—706 million people. An unacceptably large number of people. But we should also know that the trend is moving in the right direction. The number of people in extreme poverty is falling. It is possible to end extreme poverty.

Remembering these facts about the world brings to mind why I think it is important to get engaged in global development. The statistics on the current state of the world make clear that we cannot be complacent about the world as it is today. Especially because progress is uneven, and in sub-Saharan Africa progress has been slower, but is not absent. The statistics on global change over time tell us that it is possible to work for a better world. The number of child deaths is dropping. The challenges of rapid population growth will not continue indefinitely. And the number of people in extreme poverty is falling.

Let’s continue in this direction. Our past successes should encourage us to work for more progress.

The great epidemiologist Larry Brilliant once said that “outbreaks are inevitable, but pandemics are optional.” I thought about this quote and what it reveals about the COVID-19 pandemic often while I was working on my new book.

On the one hand, it’s disheartening to imagine how much loss and suffering could’ve been avoided if we’d only made better choices. We are now more than two years into the pandemic. The world did not prioritize global health until it was too late, and the result has been catastrophic. Countries failed to prepare for pandemics, rich countries reduced funding for R&D, and most governments failed to strengthen their health systems. Although we’re finally reaching the light at the end of the tunnel, COVID still kills several thousand people every day.

On the other hand, Dr. Brilliant’s quote makes me feel hopeful. No one wants to live through this again—and we don’t have to. Outbreaks are inevitable, but pandemics are optional. The world doesn’t need to live in fear of the next pandemic. If we make key investments that benefit everyone, COVID-19 could be the last pandemic ever.

This idea is what my book, How to Prevent the Next Pandemic , is all about. I’ve been part of the effort to stop COVID since the early days of the outbreak, working together with experts from inside and out of the Gates Foundation who have been fighting infectious diseases for decades. I’m excited to share what I've learned along the way, because our experience with COVID gives us a clear pathway for how to be ready next time.

So, how do we do it? In my book, I explain the steps we need to take to get ready. Together, they add up to a plan for eliminating the pandemic as a threat to humanity. These steps—alongside the remarkable progress we’ve already made over the last two years in creating new tools and understanding infectious diseases—will reduce the chance that anyone has to live through another COVID.

Imagine a scenario like this: A concerning outbreak is rapidly identified by local public health agencies, which function effectively in even the world’s poorest countries. Anything out of the ordinary is shared with scientists for study, and the information is uploaded to a global database monitored by a dedicated team.

If a threat is detected, governments sound the alarm and initiate public recommendations for travel, social distancing, and emergency planning. They start using the blunt tools that are already on hand, such as quarantines, antivirals that protect against almost any strain, and tests that can be performed anywhere.

If this isn’t sufficient, then the world’s innovators immediately get to work developing new tests, treatments, and vaccines. Diagnostics in particular ramp up extremely fast so that large numbers of people can be tested in a short time. New drugs and vaccines are approved quickly, because we’ve agreed ahead of time on how to run trials safely and share the results. Once they’re ready to go into production, manufacturing gears up right away because factories are already in place and approved.

No one gets left behind, because we’ve already worked out how to rapidly make enough vaccines for everyone. Everything gets where it’s supposed to, when it’s supposed to, because we’ve set up systems to get products delivered all the way to the patient. Communications about the situation are clear and avoid panic.

And this all happens quickly. The goal is to contain outbreaks within the first 100 days before they ever have the chance to spread around the world. If we had stopped the COVID pandemic before 100 days, we could’ve saved over 98 percent of the lives lost.

I hope people who read the book come away with a sense that ending the threat of pandemics forever is a realistic, achievable, and essential goal. I believe this is something that everyone—whether you’re an epidemiologist, a policymaker, or just someone who’s exhausted from the last two years–should care about.

The best part is we have an opportunity to not just stop things from getting worse but to make them better. Even when we’re not facing an active outbreak, the steps we can take to prevent the next pandemic will also make people healthier, save lives, and shrink the health gap between the rich and the poor. The tools that stop an outbreak can also help us find and treat more HIV cases. They can protect more children from deadly diseases like malaria, and they can give more people around the world access to high quality care.

Shrinking the health gap was the life’s work of my friend Paul Farmer, who tragically died in his sleep in February. That’s why I’m dedicating my proceeds from this book to his organization Partners in Health, which provides amazing health care to people in some of the poorest countries in the world. I will miss Paul deeply, but I am comforted by the knowledge that his influence will be felt for decades to come.

If there’s one thing the world has learned over the last two years, it’s that we can’t keep living with the threat of another variant—or another pathogen—hanging over our heads. This is a pivotal moment. There is more momentum than ever before to stop pandemics forever. No one who lived through COVID will ever forget it. Just like a war can change the way a generation looks at the world, COVID has changed the way we see the world.

Although it may not always feel like it, we have made tremendous progress over the last two years. New tools will let us respond faster next time, and new capabilities have made us better prepared to fight deadly pathogens. The world wasn’t ready for COVID, but we can choose to be ready next time.

It’s Mosquito Week again on the Gates Notes. This year I’m exploring some of the science behind malaria and other mosquito-borne diseases. You can read below about how gene editing could play a key role in eradicating malaria. I’ve also written about amazing advances in tracking the disease and how the parasite is a deadly shapeshifter.

Humans have spent thousands of years inventing new ways to kill mosquitoes. The Romans did it by draining swamps. Today you might have a bug zapper in your back yard. In low- and middle-income countries, it’s common to see people spraying insecticides or setting up sticky traps baited with sugar.

But evolution is smart. It is one-upping us by creating mosquitoes that are harder to kill. In sub-Saharan Africa and parts of South America and southeast Asia, we are seeing an alarming number of mosquitoes that can withstand insecticides.

This is especially problematic for the fight against mosquito-borne diseases like malaria. To eradicate these diseases, we need new tools to complement the ones we already have.

Our foundation is backing a lot of different advances. One that I’m especially excited about is a set of techniques for genetically modifying mosquitoes that could dramatically reduce the number of disease-carrying insects in certain areas.

What is cool about these genetic techniques is how precise they can be. Precision matters because out of more than 3,000 species of mosquitoes, only five are responsible for causing most cases of malaria. Of those, only females spread the disease, because they’re the only ones that bite humans. (They do it when they need extra protein for reproduction. Experts call it “taking a blood meal.”) The males just drink nectar.

The promise of gene editing is that, instead of killing a bunch of mosquitoes indiscriminately, we could eliminate only the dangerous ones in a particular area. That would buy us time to cure all the people there of malaria. Then we could let the mosquito population return without the parasite.

One exciting gene-editing technique is called gene drive. The term covers several different approaches, but the basic idea is to use the CRISPR method to rewrite the usual rules of inheritance. Normally, for any given gene, there’s a 50 percent chance that a parent with that gene will pass it on to a child. (It is competing with one from the other parent, and only one of the two can win.) With gene drive, the odds go up to 100 percent. You give a few mosquitoes an edited gene that inserts—or drives—itself into all their offspring. When those mosquitoes mate with wild mosquitoes, all their children will have the edited gene, and over time it will make its way through the entire population.

Imagine if blue-eyed mosquitoes had only blue-eyed children, no matter what color their partners’ eyes were. Eventually, every mosquito in that population would have blue eyes.

This chart shows you how gene drive eventually spreads a gene throughout an entire population:

There’s no reason to think gene drive is even feasible in humans, let alone advisable. There are also serious questions surrounding the use of this technology on insects, which I will get to in a moment. But first I want to give you two examples of how it works.

One is the colorfully named X-shredder. As you might remember from biology class, the sex of a mosquito is determined partly by the sex chromosomes it inherits from its parents. Females got one X chromosome from each parent; males got an X from their mother and a Y from their father.

In 2014, scientists at Imperial College London and the Fred Hutchinson center here in Seattle were able to edit a protein in male mosquitoes so that it shreds the X chromosomes in their sperm. As a result, the males pass along mostly Y chromosomes, so most of their offspring will be males. Thanks to gene drive, those offspring will also have the edited protein, so most of their children will be males.

Within a few generations, the male/female ratio gets out of whack, and eventually the species dies off in that area.

Another example involves the doublesex gene, which in mosquitoes works along with the sex chromosome to determine whether an insect turns out male or female. Last year, researchers at Imperial College London found that females with edited doublesex genes develop a mix of male and female organs, including male genitalia and a proboscis that is too flimsy to break human skin. They can’t reproduce, so the population shrinks; and they can’t take a blood meal, so they won’t spread the parasite.

The doublesex edit doesn’t affect males, although thanks to gene drive, they will pass it to their offspring, which is how it keeps spreading through the population.

We know gene-drive technology works in the lab. When the Imperial College researchers put 150 males carrying a copy of the doublesex edit in a small cage with 450 wild-type mosquitoes, the population died off within a few months (about 10 generations). The sex bias edit produced similar results.

The next step is to run tests in larger cages and, eventually, get permission from governments to do them outdoors. We need to understand things like: What’s the impact on the food chain if a certain species of mosquito starts dying off? How many altered insects would we need to introduce? How long do we need the mosquitoes to be gone? Last year, the government of Burkina-Faso agreed to allow the release of sterile, non-gene-drive mosquitoes in the wild so researchers could begin to study some of these questions.

As I mentioned, social and regulatory issues also come into play. For example, because mosquitoes don’t exactly respect national boundaries, neighboring countries will probably need to agree on the rules surrounding the use of gene-editing technology. Policymakers and scientists have been debating these questions in forums like the World Health Organization and the African Union’s development agency, and they are moving toward a consensus.

I think we can have the regulatory approvals in place by 2024 and the first gene-drive mosquitoes ready for use by 2026. Although this technique will never replace the other tools we have for fighting malaria, I’m optimistic that it could become one more important weapon in eradicating the disease.

Two of the things I love most about my job are getting to see amazing innovations and talk to remarkable people. During a recent trip to New York, I got to check both boxes. I met a woman named Papa Blandine Mbwey who is using a revolutionary new invention to help more kids get vaccinated.

Blandine has worked as a vaccinator in a remote part of the Democratic Republic of the Congo for over a decade. Most days, she travels on foot to villages all over her region so she can vaccinate kids who live too far from a health clinic to make the trip themselves.

Blandine’s job is complicated by a simple fact: vaccines must be kept between 2 and 8° C. If they get too warm, they spoil. If they get too cold, the water in them freezes, and they can stop working. Vaccines must stay within this temperature range through each step of what’s called the “cold chain.”

By the time Blandine reaches the children, the vaccines she’s carrying have traveled nearly 5,100 miles. They could have spoiled at any point during that journey, but vaccines are particularly at risk during the last two stops.

First there’s the health clinics where vaccinators like Blandine usually pick up their supply of vaccines. Many of these clinics are in areas with frequent power outages or no electrical grid at all, which means the refrigerators can’t always keep the vaccines cold.

But even if the vaccines survive the clinic, they still need to make it to the children. Most vaccinators carry them in ice-lined coolers. If you’ve used a cooler to keep your drinks cold at a picnic, you know the big problem with ice: it starts melting as soon as you take it out of the freezer. This means that some of the kids never get vaccinated, because coolers can’t keep vaccines cold long enough to reach them.

Several years ago, I asked a group of inventors called Global Good that I support to take on the cold chain problem. They came up with two remarkable innovations that are changing the game for vaccinators like Blandine.

The first is the MetaFridge. Although it looks like a regular refrigerator, MetaFridge has a hidden superpower: it keeps vaccines cold without power for at least five days. The electrical components are designed to keep working through power surges and brown-outs. During extended outages, an easy-to-read screen tells you how much longer it can stay cool without power so health workers know when to run a generator or move vaccines elsewhere. And if the fridge stops working properly, it transmits data remotely to a service team so they can fix it before vaccines are at risk of spoiling.

The other innovation Global Good invented is the Indigo cooler, which is the device you see Blandine using in the video above. It keeps vaccines at the right temperature for at least five days with no ice, no batteries, and no power required during cooling.

It sounds counterintuitive, but the Indigo needs heat before you can use it. When exposed to a heat source, water inside its walls evaporates and moves into a separate compartment. It can then sit on a shelf for months after heating, ready for use.

When it’s finally time to head out to the children, you open a valve, and the water starts moving back where it started. Because the pressure inside the Indigo has been lowered to the point where water evaporates at 5° C, the water particles take heat with them (the way sweating lowers your body temperature) and cool the storage area down to the perfect temperature for vaccine storage.

Both inventions are already making an impact in the field. A Chinese manufacturer started selling the MetaFridge last year, and a new solar-powered version will hit the market soon. One of the biggest surprises so far is just how much we’ve learned from its remote data monitoring capabilities. We knew the electrical grids in sub-Saharan Africa were unreliable, but we now know exactly how much the power fluctuates. This information will be helpful moving forward for health providers and anyone designing a product meant to work in these areas.

The Indigo is in the field trial phase. It’s still early, but the data suggests that the Indigo is allowing vaccinators to reach four times as many places as they could with the old ice-based coolers. That’s a big deal, and I’m excited to learn more.

Keeping vaccines cold when you’re delivering them to the most remote places on earth is a tough problem—and these devices show how innovation can help solve tough problems. I hope MetaFridge and Indigo inspire other inventors to find creative solutions.

Of all the things I did when I visited Cornell University recently, I probably had the most fun brushing up on how plants have sex.

Cornell is one of the world’s top universities for research on improving crops. Their work involves a lot of plant breeding. During one meeting, I got to try my hand at cross-pollinating wheat, which is a surprisingly delicate procedure. It gave me even more respect for the people who do it every day.

Cornell’s work on crop improvement also involves a lot of cutting-edge genetics. You might see the words “crop improvement” and “genetics” in the same sentence and think I’m talking about GMOs. Although Melinda and I do support research in that area—we don’t think poor farmers should be denied the choice to use any tools that might benefit them—the work I saw at Cornell is different. It’s focused on how the science of genetics can improve agriculture in other ways. And the advances are really exciting.

I got interested in crop breeding through my work with the Gates Foundation. Because most of the world’s poor people are farmers, helping farmers grow more food is one of the most powerful levers we have for fighting poverty. The faster we can improve crops—making them more nutritious or drought-tolerant, for instance—the faster we can help farmers become more productive.

My main guide was Dr. Ed Buckler, a scientist in his mid 40s who works at Cornell for the U.S. Department of Agriculture (USDA). Over the four hours we spent together I asked Ed dozens of questions (I’ve learned a lot about agriculture, but I’m still a city boy at heart), and he was always quick with an answer. Yet Ed and his colleagues aren’t just experts in their field—they’re also deeply passionate about their work. I can see why: The advances they’re working on will change people’s lives by dramatically accelerating a process that is now slow and laborious.

Here’s how it works today. Suppose you want a variety of corn with a natural resistance to a certain pest. You start by planting as much corn as you can. You wait 8 to 12 weeks for it to grow, and then you take pollen from some of the plants that aren’t infested and use it to pollinate others. If the offspring of those plants is pest-resistant, you’re in luck—your plant won the genetic lottery. If not, you have to start over. Because you’re limited by the growing season, the process can take seven to ten years.

Genetics research will cut that time in half.

Getting there takes three steps. One is to understand the crop’s genetic makeup. Ed took me on a short tour of a lab where machines called sequencers were analyzing DNA from thousands of plants. They were mapping the genes that give each plant its physical traits: its height, color, etc.

The second step is to go into the field and record those physical traits for each individual plant whose genes you’re studying. Cornell researchers are growing hundreds of acres of corn and other crops not far from campus, and they make regular treks out there to collect data. Unfortunately, I didn’t have time for a field trip on this visit.

Finally, you build a computer model that puts the two together—the genetic maps of individual plants, along with the data about their physical traits. Once you have that model, you no longer need to cross two plants and just hope for the best. You can ask the computer, “Out of all the plants I have in my field, which two should I breed in order to produce one that is pest-resistant?” Think of it as a highly sophisticated Match.com for plants.

Cornell and the USDA have already built such a model for some traits in corn; because people in rich countries eat corn, there’s a big market for better varieties. Meanwhile, crops that are eaten mostly by the poor have largely been ignored by scientists. But that’s starting to change.

With support from the British government, our foundation, and others, researchers at Cornell and the USDA are now working on a model for cassava, a root vegetable that’s a staple crop in many tropical regions. Partners in Uganda and Nigeria are growing lots of plants, recording their traits, and sending genetic samples to Cornell for sequencing. When the cassava model is finished, it will help breeders develop new varieties faster than ever. (Incidentally, I’m fascinated by cassava—and you may not know that it is responsible for the fun factor in bubble tea.)

During my visit, I learned about one trait that I had never thought about before: poundability. Over lunch with several graduate students, a Ugandan researcher named Paula Iragaba told me that women in her country do most of the work to turn cassava into flour, and they wish it were easier to process. “Women’s preferences have to be taken into account,” she said. I couldn’t agree more.

Keep in mind, none of the genetics research I saw changes the basics of plant sex. Breeders in the field still have to move pollen from one plant to another, as they have for ages. We’re just getting a lot smarter about helping them pick the best partners. And the result will be phenomenal—a much faster path to more-productive crops so that millions of people can eat better food, earn more money, and improve their lives.

When I first started traveling to Africa, I would often meet children in the villages I was visiting and try to guess their ages. I was shocked to find out how often I guessed wrong. Kids I thought were 7 or 8 years old based on how tall they were—would tell me that they were actually 12 or 13 years old.

What I was witnessing was the terrible impact of malnutrition in Africa. These children were suffering from a condition known as stunting. They were not starving, but they were not getting enough to eat, leaving them years behind in their development—and it was hard to see how they could ever catch up.

Stunting not only affects a child’s height. It also has an impact on brain development. Stunted children are more likely to fall behind at school, miss key milestones in reading and math, and go on to live in poverty. When stunted children don’t reach their potential, neither do their countries. Malnutrition saps a country’s strength, lowering productivity and keeping the entire nation trapped in poverty.

Worldwide, one in four children is stunted. Three-quarters of them live in South Asia and sub-Saharan Africa. However, while stunting has declined by more than a third in South Asia since 1990, in sub-Saharan Africa, the number of stunted children is still on the rise, up 12 million since 1990 to 56 million. Forty percent of all children in sub-Saharan Africa are stunted.

I run into a lot of people from rich countries who still think of Africa as a continent of starvation. The fact is, that’s an outdated picture (to the extent that it was ever accurate at all). Thanks to economic growth and smart policies, the extreme hunger and starvation that once defined the continent are now rare. As I saw when I was back in Africa last month with best-selling author John Green, today the issue isn’t quantity of food as much as it is quality—whether kids are getting enough protein and other nutrients to fully develop.

As Melinda and I have grown aware of the scale of this challenge, we’ve made improving nutrition a bigger priority for our foundation. One thing we’ve quickly come to appreciate is the problem’s complexity.  There’s no vaccine to prevent stunting. Proper nutrition involves eating enough food, and the right kinds, every day of your life. While the global health community is still working to understand all of the causes and solutions to malnutrition, we do know a lot about how to ensure children get the nutrition they need for a healthy start to life.

We know that getting children the right nutrition in the first 1000 days—from the start of a woman’s pregnancy until her child’s 2nd birthday – is the best down payment on their future, giving them the opportunity to grow and develop physically and mentally. We also know that exclusive breastfeeding in the first six months of a child’s life is the single most effective intervention to help the brain develop and protect against life-threatening diseases. That’s why we continue to research the best ways to address cultural beliefs and other barriers that have kept almost half of all women from using optimal breastfeeding practices.

We know kids have a hard time getting the nutrients they need when fruits, meats, and vegetables are in short supply—so fortifying staple foods like cooking oil, flour, and salt with essential vitamins and minerals can fill the gap. We’re also beginning to develop new crops that are more-nutritious--including a sweet potato that’s enriched with vitamin A—and also produce a higher yield. Not only does this help smallholder farmers earn more income that can be used to diversify their family’s diet, it also puts more nutritious food directly on their table.

Providing better health care can make a difference too. Children who receive the rotavirus vaccine, for example, have fewer bouts of diarrhea, which can drain kids of vital nutrients and make them more susceptible to infection. Likewise, clean water and sanitation play a role in improving nutrition by reducing illness and disease.

We have many great interventions on our side, but with so many factors at play it can be difficult to measure which interventions have the most impact on improving nutrition and why. If I could have one wish, I would want the world to have a better understanding of malnutrition and how to solve it.

We have much more research to do in this area and we will continue to make progress. But what’s not in doubt is the importance of giving all children the nutrition they need for a healthy start to life. Their future depends on it. So does Africa’s.

I always look forward to visiting India for the opportunity to meet people who are benefiting from projects we’re supporting in key health areas, like family planning, polio eradication, and HIV/AIDS.

On my recent trip, I spoke with several women in one of Lucknow’s urban slums who told me how grateful they are to have a choice of contraceptives. That hasn’t always been the case and there are still many poor women who don’t know about or have access to contraceptives. Efforts like the foundation-supported Urban Health Initiative are designed to change that by educating more women about contraceptive choices and practices like spacing births further apart.

This is a top health priority for the foundation because it directly affects the health (and often the survival) of poor women and their babies. And it offers them something that all mothers desire and deserve—the opportunity to provide their children with a high-quality education and the best chance of success growing up.

I started my last day in India at a Bangalore community center called Swathi’s House—a drop-in center for sex workers that’s part of a foundation-supported HIV prevention project called Avahan. The community members gave me a traditional Indian welcome, called an aarti. It was a day to celebrate, because the program is being handed off to the government for long-term support. But the real driver of success are the members themselves.

The center is run by a remarkable community-based organization called Swathi Mahila Sangha, which has approximately 8,500 members out of a population of about 19,000 sex workers in Bangalore. They provide counseling, medical help, HIV prevention training and a micro-finance bank. All of this is done with a cadre of peer educators and outreach workers. It’s a great model for self-help and empowerment.

I was touched by the community’s honesty and resolve—and their entrepreneurial spirit. Roughly half of the members now have savings accounts and their micro-finance bank has $800,000 USD in assets, with a recovery rate of nearly 100%. (I think most U.S. banks would be envious.) Thanks, in part, to their efforts, rates of HIV and sexually-transmitted diseases are down and the woman I talked with spoke of no longer feeling alone and helpless. They were proud of being able to keep their money, instead of remaining victims to “the thugs and the goons.”

Even though they are still a marginalized group, the sex workers are succeeding in advocating for their own rights and are enthusiastic about getting even more sex workers signed up and involved. There’s also been tremendous progress at the government level tackling the problem of HIV infection head-on, and Avahan and community centers like Swathi House are great examples.

I spent the last part of my trip at a gathering of a number of business leaders and philanthropists. I was the guest of two remarkable individuals. Azim Premji is the founder of Wipro and one of Asia’s biggest philanthropists. Ratan Tata is one of the country’s foremost business leaders and a member of the Tata  family well known throughout Indian industry and philanthropy. They were nice enough to invite me to make a few remarks at the beginning, but mostly it was an opportunity to listen and learn about their perspectives on philanthropy in India.

While the circumstances for giving are unique in India, it was amazing just how much their discussion sounded like the conversations I’ve had with wealthy business people and philanthropists in the U.S. and elsewhere. A few common themes emerged. People agreed it was often easier to make the money than to give it away in a thoughtful way. There was a huge feeling of personal satisfaction in their philanthropic work, and a deep sense of societal obligation to give back. With so many problems to address, deciding where to engage and how to do it weighs heavily on their minds.

The group decided they wanted to get together again to learn from one another and talk through issues of common interest. That was fantastic. India is in a new phase of its long history of charitable giving, and I am certain many of these families are going to lead the way by doing remarkable things.

It’s been a very productive and moving three days. I’m grateful I had the chance to meet with so many amazing people in a short time. I’ll post some thoughts on the trip as a whole as well as some video the week of June 11. There’s a lot to reflect on.

Ethiopia is one of the poorest countries in the world and has faced enormous challenges feeding its people and providing critical health services to mothers and their children. Yet, I returned from a recent visit excited about advances the country is making in agriculture and health.

If these innovations—which are a top priority for our foundation—succeed, they can be replicated in other African countries that also face big challenges in health and agriculture.

One factor in Ethiopia’s progress is Prime Minister Meles Zenawi and his leadership team, who have played a key role in reinventing the country’s agricultural and health systems. Making changes to either would be a big challenge in any country, so it’s even more impressive in Ethiopia, which has the second largest population of any country in Africa but a limited economic infrastructure.

Around 85 percent of the country’s population survives by growing crops on small plots of less than five acres. But frequent droughts and soils that have been depleted of nutrients often led to low crop yields and considerable food insecurity. More than half of the country’s population of 83 million is malnourished and more than 5 million households receive food aid each year.

Our foundation has been working with the Ministry of Agriculture, the county’s new Agricultural Transformation Agency, and other partners to help farmers plant higher-yielding, drought-tolerant seeds, improve soil health and fertility, and get higher prices for their crops by selling to global markets.

At the Melkassa Research Station, one of 13 government-run agricultural outposts, Dr. Markus Walsh, Sr. showed me a new, state-of-the-art technology called NIR spectroscopy that’s part of a digital revolution in agriculture. This portable device, which quickly and cheaply analyzes soil conditions, is a fantastic breakthrough that will help farmers everywhere. But it’s especially valuable in countries like Ethiopia, where farmers haven’t been able to afford laboratory tests but need to know how to amend soils to grow better crops. The spectroscopy is part of an even bigger agricultural digital information system that will provide a comprehensive and detailed map of soil properties across the country.

I also met with a number of farmers to talk about new varieties of sorghum (a grain) and beans they are growing. Beans are very important because they provide protein and people need a combination of protein and grain to have a reasonable diet.

Helping small farmers sell their crops in world markets is another important part of the work we’re supporting in Ethiopia. It’s currently a big challenge because poor farmers may not be growing the right crops for world markets and they often lack the roads, trucks, and other infrastructure necessary to enable exports. And getting foreign investors to help build this “value chain” can be difficult. But I visited one agricultural processing facility called ACOS, that is processing and shipping a variety of beans to European markets. It is jointly owned by an Italian company and Ethiopian investors and is a great example of private investment in developing countries.

What Ethiopia is doing in health is really a model system because it reaches everyone in the country. I visited the Germana Gale Health Post, where I talked to several of the more than 30,000 health extension workers who have been trained in recent years to deliver basic health education, prevention, and treatment. Most of the health workers are women, and those I met were energetic and well-trained.

These kinds of primary health services—giving vaccines, educating women about family health, and promoting hygiene and environmental sanitation—is the foundation for building good health systems in poor countries. Ethiopia’s health system also includes district health centers like the Dalocha Health Center I visited. There, they do a little bit of surgery and have more expertise and a wider variety of drugs. There are also primary hospitals that focus on higher level treatment and some emergency surgery, and general hospitals that deal with serious emergencies and high-risk and specialized care.

Ethiopia still faces some big problems. But the people I met and what I saw re-energized me and increased my optimism that the big investments we and other donors are making in health and agriculture will pay off for the people of Ethiopia and can serve as model activities in other African countries. Improving agricultural productivity and the quality of life through better health services is the key to unleashing the potential of Ethiopia and other poor countries and getting them on the road to self-sufficiency.

With continued hard work and investment the world is on a path toward something pretty incredible, the eradication of polio. In the past two decades, polio cases around the world have been reduced by 99 percent. If we can get rid of the last 1 percent, polio will become the second major infectious disease, after smallpox, that has ever been completely eliminated. There are still gaps in funding for polio eradication, and new outbreaks could reverse some of the progress made so far. But if polio is eliminated, never again will a child be crippled by this terrible virus.

We have a chance to get there because of some great efforts, particularly by the Global Polio Eradication Initiative, which involves the World Health Organization, Rotary International, the US Centers for Disease Control and Prevention (CDC) and the United Nations Children's Fund (UNICEF). The Gates Foundation is very involved in supporting polio immunization campaigns and other efforts to educate parents and communities about the importance of immunization. We’re also supporting work to improve polio surveillance and to develop better vaccines and anti-poliovirus drugs.

Northern India and northern Nigeria are two areas where polio continues to be a problem. I visited northern India in May this year to see the progress there. I was very excited to visit northern Nigeria in June, because the progress there since my last visit in February 2009 has been especially impressive. As of July 14th, only five cases due to wild polio viruses were reported in Nigeria this year, versus hundreds last year.

I spent most of my first day in Kano, one of the northern states most vulnerable to polio. I met with community leaders, visited a local health center and stopped in at an informal school where students study the Koran in Arabic. On the streets and most everywhere else we went, I noticed so many young children around. Nigeria has more people by far than any other African country, and more than 40 percent of them are under the age of 15. That makes polio immunization a big challenge. Kano had just begun a campaign to immunize more than 6 million children under the age of five.

Part of the challenge is overcoming fear and suspicion. In Kano in the past, false rumors linked immunization to sterility and HIV. Community leaders told me that because polio vaccine is free and brought to people in their homes, some people think there must be something wrong with it. Community leaders play a critically important role in helping to overcome mistrust, and a big focus of anti-polio efforts is on informing these leaders and enlisting their support.

Another ironic thing I noticed was that because polio cases have been dramatically reduced, it’s more difficult to know whether local immunization campaigns are reaching everyone they need to reach, particularly sub-populations that may be more at risk. Without many actual cases, you have to rely on other ways of monitoring immunization rates, and the different measures are sometimes quite inconsistent. I think we need to look at how to help get more reliable data to guide our efforts and ensure they’re effective.

Also of concern is the risk that progress against polio in Kano might be undermined by the virus filtering back in from neighboring countries and other parts of northern Nigeria. Increasingly, the problem needs to be approached on a regional basis.

The school we visited was very interesting. It didn’t really look like a school. There were no classrooms, just children sitting on the street, against a wall or under a tree, holding slates with Arabic script written on them. I asked one of the boys to recite the lesson from his slate, and he did.

That night in Abuja, the Nigerian capital, I had dinner with government officials including the Minister of Health, Onyebuchi Chukwu. It was interesting to learn about some of the creative approaches being used to inform Nigerians about the importance of immunization. Pro-immunization messages are being embedded in the plotlines of popular TV entertainment programs, for example. One of Nigeria’s largest mobile phone service providers has agreed to send out about 25 million free text messages on polio and health.

The next day I had a number of meetings including a session with several state governors and one with Nigeria’s new President, Goodluck Jonathan. Commitment from Nigeria’s leaders has been crucial in advancing the nation’s fight against polio.

A recurring theme I picked up from the people I talked to was the importance of using what we’ve learned and accomplished in the drive against polio to fight other illnesses such as infant diarrhea, respiratory ailments and malaria. I do believe that polio eradication helps strengthen routine immunization, which has the potential to save the lives of large numbers of children.

Wherever I go, I always find that saving children’s lives is a universal concern. I was very impressed with Nigeria’s progress against polio. I tried to encourage everyone to not let up.

While the World Summit on Food Security in Rome in November did not achieve all it should, it shined a welcome spotlight on small farmers who make up the vast majority of hungry and poor people in the world. Coming on the heels of a commitment by the G20 to invest $22 billion in developing-country agriculture, the summit provided reason to be optimistic that after decades of neglect, we’ll start investing in the single best strategy to reduce global hunger and poverty.

At the same time, I am worried that as momentum builds behind agricultural development as a long-term alternative to food aid, a growing ideological divide may cause the world to squander a real opportunity to fight hunger and poverty.

The global movement to help small farmers is increasingly divided into two camps. On one side is a technological approach focused on improving productivity. On the other side is an environmental approach that promotes sustainability. Productivity or sustainability – they say you have to choose.

A recent Time Magazine article “Different Shades of Green in Africa,”for example, pits the idea of organic development to help African farmers against the heavy input approach being promoted by the Alliance for a Green Revolution in African (AGRA) and the Bill & Melinda Gates Foundation, calling it “a battle between two very different agricultural philosophies.”

As I said during my speech at the World Food Prize in October, this is a false choice that is dangerous for the field of agricultural development.

At a time of rising population and climate change, we need both organic solutions that promote sustainability and the technological approaches that increase productivity—and there is no reason we can’t have them both.

Many environmental advocates highlight the excesses of the original Green Revolution. They have a point. The Green Revolution increased yields dramatically in many poor countries in the second half of the 20th century, but it also led to over-irrigation and over-fertilization. The next Green Revolution has to be greener than the first.

Some have tried to restrict the spread of biotechnology regardless of its potential to increase productivity. They act as if there is no emergency, even though there are already 1 billion hungry people in the world, and climate change is going to make conditions harsher in the future. The Food and Agriculture Organization estimates that developing countries will have to boost their yields by half to meet the challenge of global hunger. We simply won’t be able to meet that goal without using all the scientific tools at our disposal.

Of course, new technologies must be proven safe for farmers, consumers, and the environment before they’re adopted. That’s why countries should have a strong regulatory infrastructure guided by experts with access to the latest science-based information.

I have seen proof that agricultural science can make people’s lives better. This summer, I attended a roundtable discussion in New Delhi with scientists who developed a new variety of rice called Swarna-sub1. The amazing thing about Swarna-sub1 is that it can survive underwater for more than two weeks, which means it could revolutionize life for millions of farmers in flood-prone areas of India. The researchers used a fascinating technique called marker assisted selection to introduce a single allele, a version of a gene, into an existing rice variety to make it flood tolerant.

I also met with representatives from local NGOs, seed companies, and the government of India to talk about their plans for delivering new seeds to farmers. The government’s goal is to have more than 5 million hectares planted with Swarna-sub1 in just five years.

The tendentious debate pitting productivity against sustainability doesn’t just threaten important scientific advances. It also obscures another crucial lesson from the first Green Revolution: that developing more productive seeds is just one element of an effective strategy. In addition to new seeds, farmers also need training, access to new markets, and organizations to represent their interests. Governments need better data so they can devise sound agricultural policies. By placing so much emphasis on just one link in a very long agricultural value chain, we distract ourselves from a goal we can all agree on: helping small farmers and their families.

Success requires progress on many fronts. African countries must lead the way by spending more on agriculture. Donor countries must do a better job of listening so they can understand what poor countries really need. They should explain more clearly how the money they’re pledging will be spent. I am optimistic that these obstacles can be cleared away and that the world can tap into the opportunity offered by agricultural development. That’s why the Bill & Melinda Gates Foundation has committed more than $1.4 billion to initiatives that support small farmers.

However, if the field doesn’t move past this counterproductive debate, hungry and poor people will suffer. We have a choice: We can let our disagreements get in the way of real progress, or we can agree to help more than a billion people live healthier, happier lives.