Zoonotic intestinal protists: A cross-sectional survey of non-human primates and caregivers in zoos

Authors: ŠEJNOHOVÁ, ANNA - Institute Of Parasitology - Germany; KOUTENSKÁ, MONIKA - Institute Of Parasitology - Germany; JIRKU, MILAN - Institute Of Parasitology - Germany; BROŽOVÁ, KRISTÝNA - Institute Of Parasitology - Germany; PAVLÍCKOVÁ, ZUZANA - University Of South Bohemia; KADLECOVÁ, OLDRIŠKA - University Of South Bohemia; CINEK, ONDREJ - Charles University, Czech Republic; Maloney, Jenny; Santin-Duran, Monica; PETRŽELKOVÁ, KLÁRA - Institute Of Parasitology - Germany; JIRKU, KATERINA - Institute Of Parasitology - Germany

Submitted to: One Health
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/18/2024
Publication Date: 7/22/2024
Citation: Šejnohová, A., Koutenská, M., Jirku, M., Brožová, K., Pavlícková, Z., Kadlecová, O., Cinek, O., Maloney, J.G., Santin, M., Petrželková, K.J., Jirku, K. 2024. Zoonotic intestinal protists: A cross-sectional survey of non-human primates and caregivers in zoos. One Health. 19. Article e100862. https://doi.org/10.1016/j.onehlt.2024.100862.
DOI: https://doi.org/10.1016/j.onehlt.2024.100862

Interpretive Summary: Blastocystis and Dientamoeba fragilis are intestinal parasites of humans and other animals. They have been linked to human illness and are potentially spread through zoonotic transmission pathways. However, our understanding of what animal hosts are important reservoirs of these parasites is incomplete. Additionally, the role of genetic variation in host specificity remains to be defined. To address these issues, the presence and genetic diversity of Blastocystis and the presence of D. fragilis was explored in non-human primates in zoos in the Czech Republic and in their human caregivers. Through this work it was determined that the same genetic variants of Blastocystis could be found in non-human primates and their caregivers, supporting the potential for those genetic variants to spread through zoonotic transmission routes. Additionally, two new subtypes of Blastocystis were discovered through this work. The description of these new subtypes is an important step in clarifying the complex epidemiology of this parasite. The data produced in this study will benefit the Blastocystis research community and assist public health officials in determining the risk of zoonotic transmission of these human parasites.

Technical Abstract: Intestinal protists in the gut microbiome are increasingly studied, but their basic epidemiology is not well understood. We explored the prevalence, genetic diversity, and potential zoonotic transmission of two protists colonizing the large intestine - Blastocystis sp. and Dientamoeba fragilis - in 37 species of non-human primates (NHPs) and their caregivers in six zoos in the Czech Republic. We analyzed 179 fecal samples (159 from NHPs, 20 from humans) by qPCR. Blastocystis sp. was detected in 54.7% (98/179) of samples, in 24 NHP species and in 57.2% of NHP samples (prevalence ranged between 36 to 80%), and in 35% of human samples (prevalence ranged between 0-67%). Using next generation amplicon sequencing, nine Blastocystis subtypes (ST1-ST5, ST7, ST8, and two novel subtypes) were identified. The two new Blastocystis subtypes (named ST47 and ST48) were described using Nanopore sequencing to produce full-length reference sequences of the small subunit ribosomal RNA gene. Some subtypes were shared between NHPs and their caregivers, suggesting potential zoonotic transmission. Mixed subtype colonization was frequently observed, with 52% of sequenced samples containing two or more subtypes. Dientamoeba was found only in NHPs with a prevalence of 6%. This study emphasizes the critical role of molecular diagnostics in epidemiological and transmission studies of these protists and calls for further research to better understand their impact on public health.