Animal diseases that infect humans are a major threat to human health, and diseases often spillover to humans from nonhuman primates. In 2018 the World Health Organization added "Disease X" – an unknown pathogen of zoonotic origin that can infect human beings – to its list of diseases most in need of research and development. Now, researchers, including Dr Tamara Giles-Vernick of the Institut Pasteur, have carried out an extensive social sciences evaluation of how populations in Cameroon interact with nonhuman primates, pointing toward behaviors that could put people at risk of infection with new diseases. Their paper appeared in PLOS Neglected Tropical Diseases in December.
Zoonotic diseases—those which originate in other animal species before spilling over to humans—now constitute more than 60 percent of emerging infectious diseases. Of these zoonotic diseases, 70 percent reportedly come from wild animals. Because of the similarity between humans and nonhuman primates, these monkeys and apes serve as frequent reservoirs or amplifiers for pathogens that pose a risk to human populations.
In the new work, Tamara Giles-Vernick, Head of the Medical Anthropology and Environment Research Group at the Institut Pasteur, France, and Victor Narat, researcher at the French Center for National Scientific Research (who carried out his postdoctoral fellowship in Dr. Giles-Vernick’s research group), with their colleagues carried out real-time data collection, oral history interviews, questionnaires, and wild meat surveys to paint a full picture of the physical exposure of people in southeastern Cameroon to nonhuman primate species. Data were collected in 2016 and 2017 and included information from multiple villages and hundreds of people.
The researchers found that Cameroonian adults have frequent physical contact with primates, and more with monkeys than great apes. This contact is most often through hunting, butchering, preparing and consuming meat, but also includes injuries sustained from gorillas. Some 85% of questionnaire respondents had eaten primate meat in their lifetimes. In general, the exposure risk in any given village was directly related to the relative density of nonhuman primates and their proximity to human settlements.
Courtesy of PLOS Neglected Tropical Diseases who gave permission to use and modify its original press release.
The Agence Nationale de la Recherche (France; http://www.agence-nationale-recherche.fr) funded the study ANR-14-CE31-004, including postdoctoral salary and field missions. TGV received this funding.
The Canadian Institute for Advanced Research(https://www.cifar.ca/) provided additional funding for field investigation. TGV received this funding.
The Institut Pasteur Infection and Epidemiology Department (https://www.pasteur.fr/en/infection-and-epidemiology) provided supplemental funding for VN's salary. VN received this funding.
The Institut Pasteur International Direction (https://www.pasteur.fr/fr/international) provided supplemental funding for participation in the study by Richard Njouom, head of the Virology Department at the Centre Pasteur of Cameroon.