Chimpanzees have been found to have long-triggered leprosy in their noses, the first time the disease has been spotted in wild apes.
Previously, leprosy, a severe infection of the skin and mucous membranes, was only seen in the survivors of those caught by humans, who traditionally used it as a form of punishment. However, scientists tracked down 14 chimpanzees living in Pemba National Park in Tanzania – all of them females aged between five and 17.
They showed the team of researchers, at the Max Planck Institute for Evolutionary Anthropology in Leipzig, traces of the disease were now present in the noses of both females and males.
Scientists from the Max Planck Institute for Evolutionary Anthropology in Leipzig say leprosy in chimpanzees is rarely seen in the wild (Photo credit: Lily Koborzky)
In the same animal health study, scientists from Duke University discovered rare rhesus monkeys – such as marmosets – harbour leprosy-related lesions as well as two new leprosy-related chimp lesions.
“Our results provide stronger support for the concept that pathogens can change their ecological hosts to evolve new genetic properties. To that end, it is only a matter of time before human pathogens acquire resistance to leprosy drugs, increasing the risk of humans catching leprosy. We need to start a conversation about the possibility of reintroducing anti-leprosy drugs in the wild,” lead author and assistant professor at the Duke University Medical Center, Hervé Chéry, said.
“At this time, our research suggests that we can’t eliminate all pathogens from humans, including leprosy,” said the paper, published in Proceedings of the National Academy of Sciences.
Research on populations of leper monkeys in the jungles of Madagascar is part of a broader study into chimp behaviour. The team found that the chimps tested show normally when their group is out hunting or climbing trees, but also develop predisposed behaviours when threatened with predators, such as calling in a distress signal.
“The study also shows what we already suspected: that chimp development is complex and that they are highly adaptive in adapting their behaviours to the environment they live in,” Chéry added.