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See related articles at [[www.cmaj.ca/lookup/doi/10.1503/cmaj.191279][2]][2] and [[www.cmaj.ca/lookup/doi/10.1503/cmaj.191660][3]][3] KEY POINTS In early July, a previously healthy 37-year-old man presented to a primary care clinic with fever, sore throat, nasal congestion and migratory arthralgia

A One Health approach was developed in the province of Manitoba in 2014 to manage human and domestic animal exposures to rabies. Manitoba Rabies Central is a collaboration of 3 provincial departments responsible for animal, human, and environmental health. Since the inception of the program 537 samples from animals suspected of rabies and causing an exposure to a human or domestic animal have been evaluated with 11.3% testing positive, 85.7% testing negative, and 3.0% being unfit for testing. Most of the positive rabies test results came from skunks (52.0%), which accounted for 12.5% of submissions. Dogs and cats accounted for 52.5% of submissions; however, only 18.9% of these animals tested positive for rabies. Domestic animals were more likely to be exposed to a rabid animal (most commonly skunks) than were humans. Humans were more likely to be exposed to dogs and cats (regardless of rabies test result).

Lyme disease, the most commonly reported vector-borne disease in North America, is caused by the spirochete Borrelia burgdorferi sensu stricto, which is transmitted by Ixodes scapularis in eastern Canada and Ixodes pacificus in western Canada. Recently, the northward range expansion of I. scapularis ticks, in south-eastern Canada, has resulted in a dramatic increase in the incidence of human Lyme disease. Detecting emerging areas of Lyme disease risk allows public health to target disease prevention efforts. We analysed passive tick surveillance data from Ontario and Manitoba to i) assess the relationship between the total numbers of I. scapularis submissions in passive surveillance from humans, and the number of human Lyme disease cases, and ii) develop province-specific acarological indicators of risk that can be used to generate surveillance-based risk maps. We also assessed associations between numbers of nymphal I. scapularis tick submissions only and Lyme disease case incidence. Using General Estimating Equation regression, the relationship between I. scapularis submissions (total numbers and numbers of nymphs only) in each census sub-division (CSD) and the number of reported Lyme disease cases was positively correlated and highly significant in the two provinces (P ≤ 0.001). The numbers of I. scapularis submissions over five years discriminated CSDs with ≥ 3 Lyme disease cases from those with < 3 cases with high accuracy when using total numbers of tick submission (Receiver Operating Characteristics area under the curve [AUC] = 0.89) and moderate accuracy (AUC = 0.78) when using nymphal tick submissions only. In Ontario the optimal cut-off point was a total 12 tick submissions from a CSD over five years (Sensitivity = 0.82, Specificity = 0.84), while in Manitoba the cut-off point was five ticks (Sensitivity = 0.71, Specificity = 0.79) suggesting regional variability of the risk of acquiring Lyme disease from an I. scapularis bite. The performances of the acarological indicators developed in this study for Ontario and Manitoba support the ability of passive tick surveillance to provide an early signal of the existence Lyme disease risk areas in regions where ticks and the pathogens they transmit are expanding their range.