The Occurrence of the Granular Tape-Worm Echinococcus granulosus in Wild Game in North America

Abstract

Hydatid disease, induced by the larval stage of Echinococcus granulosus, has been reported from several localities in N. America. The cycle has typically involved native ungulates (white-tailed deer, Odocoileus virginianus, and moose, Alces americana) as the intermediate host and the timber wolf (Canis lupus) as terminal host. Such naturally occurring infestations have been reported from Minnesota and from Ontario. The present paper records the occurrence of Echinococcus in the coast deer, O. hemionus columbianus, on Vancouver Island, British Columbia, and in elk, Cervus canadensis, and mule deer, 0. h. hemionus, in the Rocky Mt. region of western Alberta. On Vancouver I. the terminal host was not discovered, but feral dogs seemed most probable. In the Rocky Mt. region the adult cestode was taken from timber wolves, one infestation was well established in the absence of wolves but in the presence of mountain lion, Felis concolor, and coyote, Canis latrans. The incidence of infestation in 352 elk slaughtered in Banff National Park in 1945-46 was 6.5%.