Prevalence of Giardia and Cryptosporidium in muskrats in northeastern Pennsylvania and New Jersey.

Giardia spp. and Cryptosporidium spp. are intestinal parasites that affect humans and animals throughout the world. Although infection with Giardia spp. is usually self-limiting, some cases result in mild to severe enteritis. Giardiasis can be treated with modern drugs. The increasing incidence of well-documented outbreaks of Cryptosporidiosis has resulted in a growing awareness of the danger of this infection. In this study, the authors examined beavers and muskrats to determine their role as reservoir hosts in the spread of these two pathogens. The authors obtained fecal samples from trapped animals and examined them to detect simultaneously the presence of Cryptosporidium oocysts and Giardia cysts. Water samples collected from the trapping locations were also tested for the same pathogens. The study showed that 65.9% of the tested muskrats were positive for Giardia spp., 50% were positive for Cryptosporidium spp., and 29.3% were infected with both parasites. The surface water tests showed three sites were positive for Cryptosporidium spp. and none for Giardia spp. These findings suggest the muskrat may be an important reservoir host for both Cryptosporidium spp. and Giardia spp.