American dog ticks along their expanding range edge in Ontario, Canada

Mark P Nelder; Curtis B Russell; Steven Johnson; Ye Li; Kirby Cronin; Tania Cawston; Samir N Patel

doi:10.1038/s41598-022-15009-9

American dog ticks along their expanding range edge in Ontario, Canada

Sci Rep. 2022 Jun 30;12(1):11063. doi: 10.1038/s41598-022-15009-9.

Authors

Mark P Nelder¹, Curtis B Russell², Steven Johnson³, Ye Li^{3

4}, Kirby Cronin^{5

6}, Tania Cawston⁵, Samir N Patel^{5

7}

Affiliations

¹ Enteric, Zoonotic and Vector-Borne Diseases; Health Protection, Operations and Response, Public Health Ontario, Toronto, ON, Canada. mark.nelder@oahpp.ca.
² Enteric, Zoonotic and Vector-Borne Diseases; Health Protection, Operations and Response, Public Health Ontario, Toronto, ON, Canada.
³ Informatics, Knowledge Services, Public Health Ontario, Toronto, ON, Canada.
⁴ Dalla Lana School of Public Health, University of Toronto, Toronto, ON, Canada.
⁵ Public Health Ontario Laboratory, Public Health Ontario, Toronto, ON, Canada.
⁶ National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, MB, Canada.
⁷ Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada.

Abstract

The American dog tick, Dermacentor variabilis, is a tick of public and veterinary health importance in North America. Using passive tick surveillance data, we document distribution changes for the American dog tick in Ontario, Canada, from 2010 through 2018. Dermacentor variabilis submissions from the public were geocoded and aggregated-from large to small administrative geographies-by health region, public health unit (PHU) and Forward Sortation Area (FSA). PHU hot spots with high rates of D. variabilis submissions were (1) Brant County, Haldimand-Norfolk and Niagara Regional in the Central West region and (2) Lambton and Winsor-Essex County in the South West region. The number of established D. variabilis populations with ≥ 6 submissions per year increased significantly during the study at regional (PHUs: 22 to 31) and local (FSAs: 27 to 91) scales. The range of D. variabilis increased similarly to the positive control (Ixodes scapularis) during the study and in contrast to the static range of the negative control (Ixodes cookei). Submission hot spots were in warmer, low elevation areas with poorly drained soils, compared to the province's low submission areas. Dermacentor variabilis is spreading in Ontario and continued research into their vector ecology is required to assess medicoveterinary health risks.

MeSH terms

Animals
Data Collection
Dogs
Ixodes*
New Jersey
Ontario / epidemiology
Rhipicephalus sanguineus*