Paul Farmer, the physician, anthropologist, and author who advocated for health care for people living in poverty across the world, died in Rwanda at 62, NPR reports.

His death was confirmed by Partners in Health, the nonprofit he co-founded in 1987. No cause of death was given.

Farmer, a Massachusetts native, was educated at Duke and Harvard universities. He worked as a physician before co-founding Partners in Health, which provides medical care to people in countries including Haiti, Rwanda, and Mexico.

In 2003, journalist Tracy Kidder told Farmer’s story in his book Mountains Beyond Mountains; the book became a New York Times bestseller and introduced Farmer to the world at large. Kirkus called the book a “skilled and graceful exploration of the soul of an astonishing human being.”

Farmer’s own books include Pathologies of Power, Haiti After the Earthquake, and, most recently, Fevers, Feuds, and Diamonds, a book about the 2014 Ebola outbreak in West Africa, which was published just months after the Covid-19 pandemic began in 2020.

Farmer was remembered on social media by his admirers. Ford Foundation President Darren Walker tweeted, “The passing of Paul Farmer—a person so full of life, infectious optimism and vibrant joy—is devastating for those of us who knew and loved him. A world with hope is difficult to imagine without Paul.”

And Paul Kagame, the president of Rwanda, wrote, “He combined many things hard to find in one person. The weight of his loss is in many ways personal, to the country of Rwanda (which he loved and to which he contributed so much during its reconstruction), to my family and to myself. I know there are many who feel this way in Africa and beyond.”

Michael Schaub is a Texas-based journalist and regular contributor to NPR.