Genetic diversity, prevalence and risk factors of trichomonads from captive non-human primates in China

Trichomonads are flagellated protozoan parasites, some of which are pathogenic and have zoonotic potential. This study aimed to investigate the prevalence, genetic diversity, phylogenetic relationships and risk of trichomonads in captive non-human primates (NHPs) in China. Data on trichomonad prevalence and diversity in captive NHPs are limited. To better understand the prevalence status of trichomonads, fecal samples from 356 NHPs across three zoos in China were collected, including Cercopithecidae (n = 179), Hylobatidae (n = 64), Cebidae (n = 65), Callithrix (n = 48). The ITS-1/5.8S/ITS-2 gene was amplified using polymerase chain reaction (PCR) to investigate the prevalence rate and species identification of trichomonads. Phylogenetic analysis was then conducted to assess evolutionary relationships and genetic characteristics. A prevalence of 22.19 % (79/356) was observed in NHPs, with younger animals, Cebidae and living condition at higher risk of infection. Six trichomonad species in NHPs were identified, including Tetratrichomonas spp., Honigbergiella spp., Simplicimonas spp., Pentatrichomonas hominis, Hypotrichomonas hampli, and Trichomitus spp. These findings highlight the presence of multiple trichomonads species in NHPs, which may serve as potential sources of zoonotic, and emphasize the necessity of improving health management strategies and strengthening monitoring of zoonotic disease transmission risks within NHP populations.