Leprosy, ancient scourge of humans, found to assail wild chimpanzees

Conservation scientist Kimberley Hockings was worried. In 2017, photos from camera traps in Guinea-Bissau’s Cantanhez National Park, where she works, revealed several chimpanzees with terrible lesions on their faces. Hockings emailed wildlife veterinarian Fabian Leendertz. “I have NEVER seen this in chimps,” Leendertz, who works at the Robert Koch Institute in Berlin, wrote back. Then a few months later, Leendertz saw a similar photo from his own research site in Ivory Coast, hundreds of kilometers away. Could it be the same disease? Now, a new preprint by the two researchers gives a surprising answer: Chimps in both West African sites suffer from leprosy, a disease never before documented in wild chimpanzees. The strains in each park appear unrelated, and they are unlikely to have come from contact with humans, the authors argue. The finding could indicate an unknown source of leprosy in the wild and reveal new clues about a still-mysterious disease.