Prevalence and distribution of Echinococcus species in domestic dogs and wild canids in Pennsylvania: KeyScreen™ GI Parasite PCR testing of fecal samples

<i>Echinococcus</i> species are zoonotic cestodes found worldwide, posing a risk to humans and animals. <i>Echinococcus multilocularis</i> and <i>E. granulosus</i> sensu lato (s.l.) are both a concern in North America. Wild and domestic canids are definitive hosts, while rodents and ruminants are intermediate hosts for <i>E. multilocularis</i> and <i>E. granulosus</i> s.l., respectively. Humans can be alternative intermediate hosts for both <i>Echinococcus</i> species, and domestic dogs can serve as intermediate hosts for <i>E. multilocularis</i>. Recent <i>Echinococcus</i> detections in the eastern United States and Canada indicate a need for surveillance for these parasites. In total, we tested 27,293 fecal samples: pet dogs (<i>n</i> = 26,979), hunting dogs (<i>n</i> = 52), and wild canids (<i>n</i> = 262, including coyotes (<i>Canis latrans</i>), red fox (<i>Vulpes vulpes</i>), and gray fox (<i>Urocyon cinereoargenteus</i>)) from Pennsylvania, USA using the KeyScreen™ GI Parasite PCR. This PCR can detect and differentiate <i>E. multilocularis, E. granulosus</i> s.l., and <i>Taenia</i> spp. Infection with <i>Echinococcus multilocularis</i> was detected in four individuals: two gray foxes from Erie and Clearfield counties and two coyotes from Lackawanna and Susquehanna counties. Additionally, one coyote was positive from Wyoming county for <i>E. canadensis</i> (G8), an <i>E. granulosus</i> s.l. species. No pet dogs or hunting dogs were positive for either <i>Echinococcus</i> species. Wild canids from multiple counties were positive for <i>Taenia</i> species, but no domestic pet dogs or hunting dogs were positive. These findings expand the known range of <i>Echinococcus</i> species in Pennsylvania wild canids and demonstrate that KeyScreen™ is a valuable and rapid tool for detecting <i>Echinococcus</i> spp. in canid fecal samples.