The last mile
We’re closer than ever to eradicating polio
...And closer than ever to seeing a resurgence.

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.