Prevalence Of, Risk Factors For, and Zoonotic Potential of Giardia Spp

Giardia duodenalis is an intestinal protozoal parasite capable of causing both clinical and subclinical disease in a broad range of species, including humans and cats. The parasite has a ubiquitous distribution and infection occurs worldwide in nearly all mammals. Giardia infection in cats may not be associated with any clinical signs, but affected cats most commonly exhibit acute small bowel diarrhea with or without weight loss. Estimates of the prevalence in cats fall within a broad range (between 1-10%), with higher rates generally reported for group housed cats. Confusion exists regarding the significance of Giardia in cats and the need for surveillance and treatment of cats in animal shelters as data regarding the zoonotic potential of Giardia-infected cats are lacking. Cysts of the various genotypes are morphologically indistinguishable by light microscopy and advanced molecular techniques are required to determine their assemblage type. Little information exists regarding the differences among the various assemblages, with the principal distinction being host range and possibly geographic location. Assemblages A and B have the widest host range and cause disease in humans. Assemblages C and D are found mainly in dogs, E in livestock, F in cats, and G in rodents. Mixed infections are possible. The purpose of this study was to estimate the prevalence of Giardia in cats available for adoption at an animal shelter in central New York, assess zoonotic risk by determining the assemblage type(s) found in cats shedding Giardia cysts, and determine risk factors for infection. Once monthly for 5