Do apes smell like humans? The role of skin bacteria and volatiles of primates in mosquito host selection

Anthropophilic mosquitoes are effective vectors of human disease because of their biting preferences. To find their host, these mosquitoes are guided by human odours, primarily produced by human skin bacteria. By analysing the skin bacterial and skin volatile profiles of humans, bonobos, chimpanzees, gorillas, lemurs and cows, we investigated whether primates that are more closely related to humans have a skin bacterial community and odour profile that is similar to that of humans. We then investigated whether this affected discrimination between humans and closely related primates by anthropophilic and zoophilic mosquitoes that search for hosts. Humans had a lower skin bacterial diversity than the other animals and their skin bacterial composition was more similar to that in other primates than it was to the skin bacteria of cows. Like the skin bacterial profiles, the volatile profiles of the animal groups were clearly different from each other. The volatile profiles of cows and lemurs were more closely related to the human profiles than expected. Human volatiles were indeed preferred above cow volatiles by anthropophilic mosquitoes and no preference was observed when tested against non-human primate odour, except for bonobo volatiles, which were preferred over human volatiles. Unravelling the differences between mosquito hosts and their effect on host selection is important for a better understanding of cross-species transmission of vector-borne diseases.