Echinococcus in wild canids in Québec (Canada) and Maine (USA)

PLoS Negl Trop Dis. 2018 Aug 20;12(8):e0006712. doi: 10.1371/journal.pntd.0006712. eCollection 2018 Aug.

Abstract

Zoonotic Echinococcus spp. cestodes (E. canadensis and E. multilocularis) infect domestic animals, wildlife, and people in regions of Canada and the USA. We recovered and quantified Echinococcus spp. cestodes from 22 of 307 intestinal tracts of wild canids (23 wolves, 100 coyotes, 184 red and arctic foxes) in the state of Maine and the province of Québec. We identified the species and genotypes of three Echinococcus spp. cestodes per infected animal by sequencing mitochondrial DNA at two loci. We further confirmed the absence of E. multilocularis by extracting DNA from pools of all cestodes from each animal and running a duplex PCR capable of distinguishing the two species. We detected E. canadensis (G8 and G10), but not E. multilocularis, which is emerging as an important human and animal health concern in adjacent regions. Prevalence and median intensity of E. canadensis was higher in wolves (35%, 460) than coyotes (14%, 358). This parasite has historically been absent in Atlantic regions of North America, where suitable intermediate hosts, but not wolves, are present. Our study suggests that coyotes are serving as sylvatic definitive hosts for E. canadensis in Atlantic regions, and this may facilitate eastward range expansion of E. canadensis in the USA and Canada. As well, compared to wolves, coyotes are more likely to contaminate urban green spaces and peri-urban environments with zoonotic parasites.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Canidae / parasitology*
  • Echinococcosis / epidemiology
  • Echinococcosis / veterinary*
  • Echinococcus / isolation & purification*
  • Maine / epidemiology
  • Quebec / epidemiology

Grants and funding

Funding for this project was provided by the National Center for Veterinary Parasitology (http://www.ncvetp.org/), the Western College of Veterinary Medicine Interprovincial Fund, and NSERC USRA. Additional funding was provided by federal Pittman-Robertson Wildlife Restoration funds from the USFWS’ Wildlife and Sport fish Restoration Program (https://wsfrprograms.fws.gov/subpages/grantprograms/wr/wr.htm), and revenues from state hunting and trapping licenses. Funding for the Zoonotic Parasite Research Unit at the University of Saskatchewan comes from the Canadian Foundation for Innovation Leaders Opportunity Fund. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.