Canine infection with Borrelia burgdorferi, Dirofilaria immitis, Anaplasma spp. and Ehrlichia spp. in Canada, 2013–2014

Abstract

BackgroundCanine test results generated by veterinarians throughout Canada from 2013–2014 were evaluated to assess the geographical distribution of canine infection with Borrelia burgdorferi, Dirofilaria immitis, Ehrlichia spp., and Anaplasma spp.MethodsThe percent positive test results of 115,636 SNAP® 4Dx® Plus tests from dogs tested were collated by province and municipality to determine the distribution of these vector-borne infections in Canada.ResultsA total of 2,844/115,636 (2.5%) dogs tested positive for antibody to B. burgdorferi. In contrast, positive test results for D. immitis antigen and antibodies to Ehrlichia spp. and Anaplasma spp. were low, with less than 0.5% of dogs testing positive for any one of these three agents nationwide. Provincial seroprevalence for antibodies to B. burgdorferi ranged from 0.5% (Saskatchewan)–15.7% (Nova Scotia); the areas of highest percent positive test results were in proximity to regions in the USA considered endemic for Lyme borreliosis, including Nova Scotia (15.7%) and Eastern Ontario (5.1%). These high endemic foci, which had significantly higher percent positive test results than the rest of the nation (P < 0.0001), were surrounded by areas of moderate to low seroprevalence in New Brunswick (3.7%), Quebec (2.8%), and the rest of Ontario (0.9%), as well as northward and westward through Manitoba (2.4%) and Saskatchewan (0.5%). Insufficient results were available from the westernmost provinces, including Alberta and British Columbia, to allow analysis.ConclusionIncreased surveillance of these vector-borne disease agents, especially B. burgdorferi, is important as climate, vector range, and habitat continues to change throughout Canada. Using dogs as sentinels for these pathogens can aid in recognition of the public and veterinary health threat that each pose.

ACVIM consensus update on Lyme borreliosis in dogs and cats

“…Other Bb‐sl species causing human LB (ie, B. mayonii in upper Midwestern states; B. afzelii, B. bavariensis, B. garinii, and B. spielmanni in Europe) are not known to cause illness in dogs. The main tick vector for Bb is the 3‐host tick Ixodes scapularis in Northeastern, Mid‐Atlantic, upper Midwestern states, and adjacent areas of Canada (http://www.capcvet.org/parasite-prevalence-maps. Accessed January 5, 2018); I. pacificus in the Pacific states and Canada; and, I. ricinus in Europe.…”

Regional and Local Temporal Trends of Borrelia burgdorferi and Anaplasma spp. Seroprevalence in Domestic Dogs: Contiguous United States 2013–2019

“…However, there is no physical barrier between the northern US and southern Canadian border to prevent the movement of ticks and B. burgdorferi reservoir hosts. There is a growing recognition of canine Lyme disease in Canada along with increased geographic distribution and density of Ixodes scapularis, increased numbers of B. burgdorferiinfected ticks, increased human cases (74) and increased seroprevalence in dogs (75,76). Canadian veterinarians and human healthcare providers should take the same precautions as those in the USA practicing in these transitional zones.…”

Prevalence of Borrelia burgdorferi, Anaplasma spp., Ehrlichia spp. and Dirofilaria immitis in Canadian dogs, 2008 to 2015: a repeat cross-sectional study

“…This widespread testing provides abundant prevalence data and an avenue for surveillance through analyses of large datasets of reported test results for vector-borne pathogen exposure and infection in dogs. This technique has been used to monitor for pathogen prevalence in dogs in the USA and Canada over the past decade [5, 12, 13]. Reported prevalence of canine vector-borne pathogens in Canada has varied by study, with respect to variation in geography (local and regional), year performed and test methodology [5, 14–18].…”