Occurrence and Genetic Diversity of Protist Parasites in Captive Non-Human Primates, Zookeepers, and Free-Living Sympatric Rats in the Córdoba Zoo Conservation Centre, Southern Spain

Abstract

Little information is currently available on the epidemiology of parasitic and commensal protist species in captive non-human primates (NHP) and their zoonotic potential. This study investigates the occurrence, molecular diversity, and potential transmission dynamics of parasitic and commensal protist species in a zoological garden in southern Spain. The prevalence and genotypes of the main enteric protist species were investigated in faecal samples from NHP (<i>n</i> = 51), zookeepers (<i>n</i> = 19) and free-living rats (<i>n</i> = 64) by molecular (PCR and sequencing) methods between 2018 and 2019. The presence of <i>Leishmania</i> spp. was also investigated in tissues from sympatric rats using PCR. <i>Blastocystis</i> sp. (45.1%), <i>Entamoeba dispar</i> (27.5%), <i>Giardia duodenalis</i> (21.6%), <i>Balantioides coli</i> (3.9%), and <i>Enterocytozoon bieneusi</i> (2.0%) (but not <i>Troglodytella</i> spp.) were detected in NHP. <i>Giardia duodenalis</i> (10.5%) and <i>Blastocystis</i> sp. (10.5%) were identified in zookeepers, while <i>Cryptosporidium</i> spp. (45.3%), <i>G. duodenalis</i> (14.1%), and <i>Blastocystis</i> sp. (6.25%) (but not <i>Leishmania</i> spp.) were detected in rats. <i>Blastocystis</i> ST1, ST3, and ST8 and <i>G. duodenalis</i> sub-assemblage AII were identified in NHP, and <i>Blastocystis</i> ST1 in zookeepers. <i>Giardia duodenalis</i> isolates failed to be genotyped in human samples. In rats, four <i>Cryptosporidium</i> (<i>C. muris</i>, <i>C. ratti</i>, and rat genotypes IV and V), one <i>G. duodenalis</i> (assemblage G), and three <i>Blastocystis</i> (ST4) genetic variants were detected. Our results indicate high exposure of NHP to zoonotic protist species. Zoonotic transmission of <i>Blastocysts</i> ST1 was highly suspected between captive NHP and zookeepers.