Prevalence, molecular epidemiology, and zoonotic potential of Entamoeba spp. in nonhuman primates in China

Amebiasis is a major public-health concern. It has a global distribution, and is listed as the third leading parasitic cause of human mortality. To survey the prevalence and assess the potential zoonotic transmission of Entamoeba spp. in nonhuman primates (NHPs) in China, 2688 fresh fecal specimens were collected from NHPs reared in farms or zoos/parks or free ranging in 13 districts. The overall prevalence of Entamoeba spp. infection determined with microscopy analysis was 39.4% (1059/2688). Higher infection rates were detected in the free ranging group (41.1%, 169/411) and in animals <1year old (58.7%, 556/947). Gene fragments were successfully amplified 463 (87.2%) out of the 531 selected specimens (approximately half of the total microscopy-positive specimens). Polymerase chain reaction (PCR) amplification identified 386 (83.4%) Entamoeba dispar and 287 (62.0%) E. coli infections, and among these, 210 (45.4%) were mixed infections. And that the E. dispar and E. coli had also been detected in humans. In phylogenetic analysis, the E. dispar and E. coli sequences clustered with reference E. dispar and E. coli, respectively. In conclusion, nonhuman primates infected with Entamoeba species, with high prevalence and zoonotic potential, should be considered when evaluating the maintenance of Entamoeba spp. and its transmission between animal reservoirs and humans.