Cryptosporidium and Blastocystis sp infections in wild primates from urban and peri-urban centres in Kenya

Evidence of pathogen cross transmission between humans and primates has raised concerns about the potential impact of zoonotic pathogen transmission on primate and human health, and primate conservation. Cryptosporidium infection has been recorded in many primate species, indicating that they are likely to serve as potential reservoirs for human infections. We conducted molecular characterization of Cryptosporidium species infecting wild primates for insights into the little-known zoonotic transmission cycles in urban and peri-urban centres in Kenya. Rectal swabs were collected from a total of 65 primates, DNA extracted and screened by nested polymerase chain reaction. Overall, 43.08% of all the primates sampled were found positive for Cryptosporidium species with most infections occurring in adults. Positive cases of Cryptosporidium sp infection were distributed across all the study sites. Three of four sampled primate species (Papio anubis, Chlorocebus aethiops, Cercopithecus mitis) were positive for Cryptosporidium infections; one (Cercopithecus ascanius schmidts) was not. Sequencing results further revealed the presence of Blastocystis species. Strong bootstrap support showed a clear clustering of both Cryptosporidium and Blastocystis species obtained from this study with human isolates. In conclusion, both parasites have zoonotic potential and our findings highlight the importance of periodic surveillance of wild primate populations for zoonoses. We trapped free-raging nonhuman primates (NHPs) in 2018 and 2019 from natural urban wildlife populations within five urban and peri-urban centres of selected towns in Kenya: in the western part of the country Kisumu, Kakamega, central Murang’a and on along the coast Mombasa and Kilifi. Sampling was carried out as previously described (Maamun et al., 2011, Jeneby et al.,, 2011). To avoid re-trapping of study subjects, we applied a non-toxic dye to the fur to identify sampled individuals, An authorised wildlife veterinarian physically examined the animals under anaesthesia and recorded their general health, sex and age group as described Nyamota et al., (2020) and Mbuthia et al., (2021). Sampled primates included Papio anubis (olive baboon), Chlorocebus aethiops (African green monkey), Cercopithecus mitis (Sykes monkeys) and Cercopithecus ascanius schmidts (red-tailed monkey). Faecal samples were collected from the rectum via swabbing and stored in 70% ethanol for molecular assays.