Echinococcus spp. Tapeworms in North America

Abstract

Alveolar and cystic echinococcosis are emerging and reemerging in Europe, Africa, and Asia. The expansion of Echinococcus spp. tapeworms in wildlife host reservoirs appears to be driving this emergence in some areas. Recent studies suggest a similar phenomenon may be occurring in North America. We describe the context of Echinococcus spp. research in North America, with a specific focus on the contiguous United States. Although studies were conducted in the United States throughout the 1900s on various sylvatic and domestic Echinococcus spp. tapeworm cycles, data are lacking for the past ≈30 years. We review previous research, provide analysis of more recent focal studies, and suggest that Echinococcus spp. tapeworms, in particular E. canadensis, may be underrecognized. As a result, we suggest that additional research and surveillance be conducted for these tapeworms in wildlife host reservoirs across the United States.

Retrospective investigation of Echinococcus canadensis emergence in translocated elk (Cervus canadensis) in Tennessee, USA, and examination of canid definitive hosts

“…Echinococcus granulosus (s.l.) has been previously documented in the southeastern USA in hogs, cattle, and domesticated dogs, although there have previously been no sylvatic cycles documented in the region [6,25,26].…”

“…Echinococcus canadensis (G8-G10) encompasses the American cervid strain and the Fennoscandian cervid strain, and cycles between cervids including moose, elk, and reindeer and canids. [4][5][6]. Members of E. granulosus (s.s.) are most frequently implicated as the causative agents of CE; however, E. ortleppi (G5), E. intermedius (G6, G7) and E. canadensis (G8, G10) are also known contribute to the global burden of human disease [4,7,8].…”

Cervical Lymphatic Filariasis in a Pediatric Patient: Case Report and Database Analysis of Lymphatic Filariasis in the United States

“…Although numerous case reports have described excision biopsies of affected lymph nodes without any apparent complications, it is unknown whether intraoperative violation of the specimen would lead to an anaphylactic reaction similar to those reported in hydatid cyst excisions. 21,[33][34][35][36] To our knowledge, no studies exist that quantify the burden of zoonotic or endemic forms lymphatic filariasis in the United States. The literature suggests that the vast majority of zoonotic cases are found in the Northeastern and mid-Atlantic states and are either due to B. beaveri or B. lepori and to our knowledge, Bancroftian and malayan filariasis in the United States has not been reported.…”

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

“…Recent findings suggest that two species of Echinococcus are emerging as threats to public health in regions of Canada and the USA [ 1 ]. These include range expansion of E .…”