Prevalence of Enterobacteriaceae in Wild Long-Tailed Macaques (Macaca fascicularis) in Thailand

An expanding human population has increased the risk of zoonosis (Devaux et al. 2019), particularly between humans and wild primates, given our close evolutionary histories and shared ecologies (Fuentes and Hockings 2010). Among the major classes of zoonotic agents, some enteropathogenic bacteria (family Enterobacteriaceae) can cause lethal diarrheal disease and pose a serious threat to all primates (McLennan et al. 2018). Enterobacteriaceae may enter primate populations from livestock, soil, human foods, and water (McLennan et al. 2018). Epidemiological studies in wild primates, both endangered species (gorillas, Gorilla gorilla; chimpanzees, Pan troglodytes) and widely distributed species that thrive in (peri)urban environments (rhesus macaques, Macaca mulatta; olive baboons, Papio anubis) speculate that primates, aside from being at risk and showing disease symptoms themselves, also act as reservoirs or carriers of Enterobacteriaceae and pose risks of bacterial spillover into overlapping humans and other wildlife (reviewed in McLennan et al. 2018).

Among the most widely distributed, socioecologically flexible primates, long-tailed macaques (Macaca fascicularis) are found throughout Southeast Asia, where frequent occurrence of human–macaque interactions have led to calls for macaque population control (Malaivijitnond et al. 2011). Such interactions may also increase macaques’ exposure to zoonotic Enterobacteriaceae, which nevertheless remain underassessed among wildlife populations in the Asian tropics. Here we report the prevalence of three Enterobacteriaceae {Salmonella spp., Shigella spp., and Shiga toxin producing Escherichia coli (STEC)] in long-tailed macaques living in human-impacted environments in Thailand.