Prevalence and intensity of gastrointestinal helminthes in habituated mountain gorillas (gorilla beringei beringei) of Bwindi Mgahinga Conservation Area

Abstract

Humans and gorillas share up to 98% of their genetic makeup, and this is a public health threat, and also a threat to the health of the endangered gorilla population through cross transmission of infections. The ease of disease and parasite transmission between gorillas, humans, and other mammals, including livestock, recorded from several shared parasites, necessitates extensive awareness of the current state of parasite burden on the mountain Gorilla. This study aimed to determine the prevalence of gastrointestinal helminthes and their intensity, paying attention to how these are affected by age, sex, and group dynamics. A cross-sectional study was non-invasively conducted, where fecal samples were analyzed and assessed using mini-FLOTAC devices for identification and EPGs. The study involved factoring the effects of age, sex, and family on the parasite egg counts and helminth prevalence. The identified helminthes were cestodes (Anoplocephala spp and Moniezia spp) and roundworms (Strongyles eggs, Strongyloides spp, Ascaris sp, Trichuris sp, and hookworms). Mean EPGS exceeding 1000 was recorded for Strongyles (7.14%), and the highest infection rate was recorded for Anoplocephala (100% all maximum prevalence), followed by Strongyles (87.5% families had maximum prevalence) between Gorilla families, while Trichuris scored the least infection in all families and all other variables studied. On the other hand, immature gorillas (sub-adults, juveniles, and infants) showed a higher parasite prevalence than adults, and the adult females had the highest prevalence among the adults. Significant differences in infections between males and females were not observed. A general uniformity in the intensity of infections with the helminths across sectors and the national parks shows that majority of these parasites are fully established in the gorilla populations and have either remained constant due to the existence of a coexistence equilibrium created over time, or there is a rising and yet hazardous outbreak of severe helminthiasis in the gorillas of BMCA. Further investigations at the molecular level to know the specific parasites to the species level, and also identifying the several entry points of these parasites into the gorilla population and their subsequent management.