Abstract

Increasing human activities in the vicinity of natural habitats may facilitate the emergence and transmission of diseases between humans, domestic animals, and wildlife species. Giardia and Cryptosporidium are two ubiquitous and potentially zoonotic protozoan parasites. They are highly prevalent in humans and domestic animals and caused significant morbidity and mortality in captive lemurs. We hypothesized that these parasites are present in the Ranomafana National Park (RNP) ecosystem (Madagascar) and may constitute a threat to endangered and endemic lemur species. The objectives of the present study were to estimate the prevalence and identify variables associated with the infections by Giardia and Cryptosporidium in various populations of humans and animals from the RNP ecosystem. Fecal samples were obtained non-invasively from human volunteers, domestic animals, and introduced rodents inhabiting three villages in the vicinity of the national park and from four species of free-ranging lemurs from the RNP. This study reports the prevalence of both protozoan in humans, domestic animals, and introduced rodents and identifies risk factors for infections in these species. Additionally, we documented for the first time the occurrence of Cryptosporidium in two species of endangered lemurs from the RNP. Endemic wildlife species may be infected by a “spill-over” of protozoan parasites from human or domestic animals.