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Every Vaclav Smil book that I own is marked up with lots of notes that I take while reading. Invention and Innovation is no exception. Even when I disagree with him, I learn a lot from him.

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The sky’s the limit

How David Sengeh is using prosthetic limbs and data science to help Sierra Leone

As chief innovation officer, David is helping his country navigate extraordinary times.


The first time I met David Moinina Sengeh, he was a college senior studying biomedical engineering. The university president asked him to introduce me at a lecture I was giving, and he charmed the crowd by talking about the ways he and I are similar (we both want people to live healthy, fulfilling lives) and how we’re different (our hairstyles). I remember being blown away by his intellect, his ambition, and his sense of humor.

It was clear that David had a bright future ahead of him, but I don’t think anyone could have predicted where he’d end up just a few years later: as Sierra Leone’s first chief innovation officer and youngest ever education minister.

David grew up in Bo, the second largest city in Sierra Leone. His uncle was a surgeon, and David would sometimes get to sit in and observe his procedures. David remembers one time when a woman showed up for her surgery only to be turned away. His uncle explained that the hospital where he worked didn’t have an ultrasound machine, and he wasn’t comfortable performing the procedure blind. Just a few hours later, during a different procedure, the lights went out in the operating room with a patient open on the table.

That’s when he realized what he wanted to do with his life: make sure every health care worker had access to the tools they needed, “I left that day thinking it was great to be a doctor, but I wanted to do biomedical engineering,” says David. So, he went abroad to study—first at a university in Norway and then at Harvard (which is where we met).

Even though he was halfway around the world, David never stopped thinking about how to help people back home—especially the more than 27,000 Sierra Leoneans who became amputees during the country’s civil war in the 1990s. Many of the disabled people he knew growing up chose not to wear prosthetics because they were painful and fit poorly. (I recently wrote about Dr. Mohamed Barrie, another hero from Sierra Leone whose career was also inspired by the same problem.)

So, David decided to spend his doctoral studies designing a more comfortable prosthetic. He ended up creating an innovative new process for fitting prosthetics. It uses an MRI to create a precise measurement of a patient’s remaining limb and a 3D printer to create a socket that fits as close to perfectly as possible.

After finishing his Ph.D. and spending some time in Nairobi studying disease data, David got a phone call that would change his life. Sierra Leone’s new president, Julius Maada Bio, wanted him to come home and serve as his country’s first ever chief innovation officer. He accepted and has been a remarkable advocate for Sierra Leone ever since. David and President Bio even joined me at our foundation’s Goalkeepers event a couple years ago to talk about their work together.

Through his role as CIO, David is working to better integrate technology into every part of Sierra Leone’s government and support the next generation of entrepreneurs. He’s helped develop data visualization tools that local leaders can use to guide decision making. His expertise has been invaluable as Sierra Leone creates new digital tools for its citizens, like a secure electronic health records system. David is doing such a great job that, in 2019, he was asked to take on a second role as the Minister of Basic and Senior Secondary Education.

Just a couple months later, the COVID-19 pandemic started. David has been deeply involved in his country’s response between his two roles.

Sierra Leone didn’t see its first case of COVID-19 until the end of March 2020, but David and his government colleagues started planning as soon as it became clear the virus posed a serious threat. “We had a vision and a strategy that was informed by the numbers from around the world,” he says.

David believes Sierra Leone’s experience during the 2014 Ebola epidemic made them better prepared for COVID-19. He gives credit to the people of Sierra Leone for immediately understanding how important it was to get the virus under control. The population took quarantine restrictions seriously from the beginning. As a result, the country has kept case counts relatively low throughout the pandemic.

“David believes Sierra Leone’s experience during the 2014 Ebola epidemic made them better prepared for COVID-19.”

Building on David’s work as CIO, Sierra Leone is using a robust data collection system to monitor COVID cases. If you start to feel ill, you can text an automated system to check your symptoms. If you need to quarantine, there’s an app you can use to make sure you receive any supplies needed to stay safe. In turn, local governments are able to use the data collected by these apps to make informed decisions about when to close things down and when to open back up.

The country was also able to reinstate a number of programs created for the Ebola outbreak. For example, in March 2020, David and his colleagues knew that the school closures that were starting to happen around the world would soon become necessary in Sierra Leone. So, they immediately began to rebuild the government’s radio teaching program. Some kids live in parts of the country so rural that radio signals don’t reach them, and the government arranged to have printed materials delivered to them. Kids who lived in bigger cities with internet access were able to take classes online.

Sierra Leone’s ability to implement lessons learned from their last epidemic gives me hope. Although Ebola was devastating for the people of Sierra Leone, the country emerged stronger and better prepared for future public health crises. I’m optimistic the same will be true for the world after COVID-19. “COVID showed us that we have to use technologies that allow us to have an impact,” says David. “This is an opportunity to reset, reimagine, and rethink.”

David Sengeh has achieved so much—and helped Sierra Leone navigate such extraordinary times—that it’s hard to believe he’s only 34 years old. I’m confident that we’ll be hearing about his amazing work for decades to come.

Meet more of my heroes in the field