Surveillance for Ixodes scapularis and Ixodes pacificus ticks and their associated pathogens in Canada, 2022

This article continues the annual series on tick surveillance in Canada, tracking two of the primary tick vectors of concern in the country, Ixodes scapularis and Ixodes pacificus, which can transmit the agent of Lyme disease alongside several other tick-borne pathogens.

This study analyzed passive and active tick surveillance data, including geographic distribution, pathogen prevalence and other characteristics to inform public health prevention.

Passive and active surveillance data were compiled from eTick (an online, image-based platform), the National Microbiology Laboratory (Public Health Agency of Canada), provincial and local public health authorities and the Canadian Lyme Disease Research Network. Descriptive statistics of ticks and their associated pathogens are presented, including infection prevalence estimates.

In 2022, a total of 7,030 I. scapularis were submitted through passive surveillance from all provinces, while 911 I. pacificus were submitted from British Columbia (n=909) and Yukon (n=2). Ixodes scapularis submissions peaked in May and again in October. For I. pacificus, submissions peaked in May with a second, smaller peak in November. Six tick-borne pathogens (Anaplasma phagocytophilum, Borrelia burgdorferi, Borrelia miyamotoi, Babesia microti, Babesia odocoilei, Powassan virus) were identified from the I. scapularis collected by dragging in Manitoba, Ontario, Québec, New Brunswick or Nova Scotia.

This report provides a summary of tick surveillance data collected in 2022. Tick characteristics and tick-borne pathogen infection prevalence were similar to previous years. Tick surveillance continues to play an important role in monitoring infection prevalence among ticks and their geographic distribution, which will help inform public health prevention and intervention efforts.