Scientists identify two primate species as hosts of a high number of pathogens that can jump to Homo sapiens .

The mammals that are most likely to pass diseases to humans are those that easily share their bacteria and viruses across species boundaries.

Disease-causing microbes that have jumped from animals to humans include Ebola virus and the coronavirus behind the 2020 epidemic in China. Maya Wardeh at the University of Liverpool, UK, and her colleagues collected information on 1,560 mammalian species, including their geographical ranges, their interactions with humans and their pathogens. Using machine-learning software, the researchers organized the animals into a network that revealed how the species share 3,986 pathogens with one another.

Mammals that share pathogens with many other species are more likely to serve as reservoirs for human diseases, the researchers found. Among the species predicted to harbour the highest number of potential human pathogens are chimpanzees (Pan troglodytes), rhesus macaques (Macaca mulatta) and red foxes (Vulpes vulpes).

The researchers say that the findings could help to identify how bacteria, viruses and other infectious agents jump to humans.