A Scoping Review on the Epidemiology of Orthobunyaviruses of Canadian Public and Animal Health Relevance in the Context of Vector Species.

Background: Mosquito-borne orthobunyaviruses are a growing priority for public and animal health in Canada. It is anticipated that disease incidence will increase due to a warming climate, given that habitats are expanding for reservoir hosts and vectors, particularly in Canada. Little is known about the ecology of primary vectors that perpetuate these orthobunyaviruses, including the viral transmission cycle and the impact of climatic and landscape factors. Methods: A scoping review was conducted to describe the current state of knowledge on the epidemiology of orthobunyaviruses relevant to Canada. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews guidelines was used to characterize studies focused on vector species. A literature search was conducted in six databases and gray literature. Eligible studies characterized orthobunyavirus epidemiology related to vector species, including viral competency, geospatial distributions, seasonal trends, and/or risk factors. Results: A total of 1734 unique citations were identified. Screening of these citations revealed 172 relevant studies, from which 87 studies presented primary data related to vectors. The orthobunyaviruses included Cache Valley virus (CVV), Jamestown Canyon virus (JCV), Snowshoe Hare virus (SHV), and La Crosse virus (LACV). Surveillance was the predominant study focus, with most citations representing the United States, specifically, LACV surveillance in Tennessee, followed by CVV and JCV in Connecticut. Orthobunyaviruses were detected in many mosquito species across multiple genera, with high vector specificity only being reported for LACV, which included Aedes triseriatus, Aedes albopictus, and Aedes japonicus. Peridomestic areas were positively associated with infected mosquitoes compared with dense forests. Orthobunyavirus infections, coinfections, and gut microbiota affected mosquito feeding and breeding behavior. Conclusion: Knowledge gaps included Canadian surveillance data, disease modeling, and risk projections. Further research in these areas, especially accounting for climate change, is needed to guide health policy for prevention of orthobunyaviral disease.

Talking treats: A qualitative study to understand the importance of treats in the pet-caregiver relationship.

Treats are a prevalent aspect of pet care, frequently given by dog and cat caregivers for varying reasons. However, recommendations of reducing or eliminating treat feeding poses a common challenge, leading to potential non-adherence surrounding weight management practices. To explore caregivers' perceptions and experiences surrounding treat feeding, we conducted five online focus groups with 24 dog and cat caregivers, recruited via an infographic shared on social media using snowball sampling. NVivo12© was used to organize and analyze verbatim transcripts using inductive thematic analysis. Outcomes illustrated three major themes: 1) the role of treats as an important tool for caregivers; 2) considerations for treat selection and provision; and 3) caregivers' need for more and better information and support related to treats. Participants emphasized the importance of treats for managing behaviours, health-related activities, and enhancing the pet-caregiver relationship. Results suggest that the diverse and valued applications of treats, caregivers' satisfaction associated with treat-giving, and perceived lack of guidance surrounding treats may present challenges for caregivers in reducing treat feeding with their pets. Findings highlight opportunities to enhance the available resources that can empower both veterinary professionals and caregivers to make well-informed decisions and foster sustainable changes in treat feeding practices to support weight management and overall health. Such considerations can improve client compliance with veterinary recommendations, to promote companion animal health and well-being while fostering the human-animal bond.

Multiple species of canine Rhipicephalus complex detected in Canada.

Multiple species of brown dog ticks have been described in the United States and the Caribbean: Rhipicephalus sanguineus sensu stricto (s.s.), also referred to as temperate lineage; R. linnaei (=tropical lineage); and R. rutilus (=southeastern Europe lineage) However, Rhipicephalus spp. are rarely recovered from dogs in Canada. To identify canine Rhipicephalus spp. in Canada and determine the influence of travel history on infestation, ticks morphologically identified as brown dog ticks (n = 93) collected from dogs (n = 13) in British Columbia, Ontario, and Québec, Canada were submitted with information regarding each dog's geographic location and travel history. Nucleic acid was extracted from available individual ticks (n = 86) and PCR was used to amplify sequences of a 12S rRNA mitochondrial gene fragment. Sequences were compared to published reference sequences of known species and a phylogenetic tree constructed. Twenty-three ticks (26.7%) consistent with R. linnaei were identified on seven dogs, including dogs from British Columbia and Ontario, with a median infestation intensity of 2 ticks/dog (mean = 3.3 ticks/dog). Sixty-one ticks (70.9%) consistent with R. sanguineus s.s. were found on two dogs from Québec and Ontario (median = 30.5 ticks/dog; mean = 30.5 ticks/dog). One dog from Ontario was infested with R. rutilus (n = 2) (2.3%). Species could not be determined for ticks from three dogs from Ontario and Québec. Most infested dogs (10/13; 76.9%) had a recent (< 1 month) international travel history. These data confirm that multiple species of canine Rhipicephalus are occasionally found in Canada and suggest introduction following travel is likely responsible for these infestations. Further analysis will allow for greater understanding of the range and diversity of canine Rhipicephalus spp. in North America and may reveal risk factors for infestation.

Cat caregivers' perceptions, motivations, and behaviours for feeding treats: A cross sectional study.

There is an abundance of research focusing on the nutritional needs of the cat, though aspects surrounding treat feeding have received far less attention. Feeding practices have the potential to cause nutrient imbalances and adverse health outcomes, including obesity. The objective of this study was to identify and describe the perceptions, motivations, and behaviours surrounding treats, and factors that influence treat feeding by cat caregivers. A 56-question online survey was disseminated to cat caregivers (n = 337) predominantly from Canada and the USA to collect data regarding caregiver and cat demographics, the pet-caregiver relationship, perceptions surrounding treats, and feeding practices and behaviours. Descriptive statistics, chi-square tests, Kruskal-Wallis one-way ANOVA, Wilcoxon signed-rank tests, and multivariable logistic regression models were used to analyze the survey data. Caregivers had varying interpretations of the term 'treat' and how treats relate to the primary diet, and these perceptions appeared to influence the quantity of treats provided. Aspects relating to the human-animal bond were highlighted as an important factor in decisions and behaviours surrounding treat feeding in our results. Though the majority (224/337, 66%) of respondents indicated they monitor their pet's treat intake, using an eyeball estimate was the most frequent (139/337, 41%) method reported to measure treats. Multivariable logistic regression results revealed feeding jerky, bones, dental treats, and table scraps in select frequencies were predictive of caregivers perceiving their cat as overweight/obese. Results provide valuable new insights to cat caregiver feeding practices and perceptions of treats and can be used to inform veterinary nutrition support to caregivers. More research is warranted to further our understanding and ensure that cats receive optimal nutrition and care.

Reporting perceived capability, motivations, and barriers to reducing treat feeding amongst dog and cat caregivers.

Obesity remains a significant concern for dogs and cats, and reducing or eliminating treats is commonly recommended as a strategy for weight management. Caregivers can struggle with adherence to such dietary recommendations. Previous research suggests caregivers are reluctant to reduce treats but there is limited understanding of the underlying factors contributing to these behaviours and decisions. The objective of this study was to explore caregivers' motivations and barriers to reducing treat feeding, and their reported capability to do so. An online questionnaire including multiple choice and Likert scale questions was disseminated to dog and cat caregivers (n=1053) primarily from Canada and the USA from September to November 2021. Caregivers commonly expressed a wide range of motivations to reduce treat feeding with their pet, though barriers to reducing treat feeding were less defined. Changing their pet's routine was a reported barrier by more than 30% of respondents and was predictive of caregivers finding reducing treat giving to be difficult (OR=1.67, p=0.017). Results from multivariable logistic regression also revealed that caregivers who consider their companion animal to be obese as more likely to perceive reducing treats to be difficult. The results highlight the role of treats in the relationship and routine of caregivers' and their pets, and the importance of considering the individualised needs and circumstance of the caregiver and pet in veterinary discussions surrounding reducing treat feeding. Identifying these perspectives can improve self-efficacy with veterinary nutrition recommendations surrounding treats.

A Scoping Review on the Epidemiology of Orthobunyaviruses in Canada, in the Context of Human, Wildlife, and Domestic Animal Host Species.

Background: Mosquito-borne orthobunyaviruses in Canada are a growing public health concern. Orthobunyaviral diseases are commonly underdiagnosed and in Canada, likely underreported as surveillance is passive. No vaccines or specific treatments exist for these disease agents. Further, climate change is facilitating habitat expansion for relevant reservoirs and vectors, and it is likely that the majority of the Canadian population is susceptible to these viruses. Methods: A scoping review was conducted to describe the current state of knowledge on orthobunyavirus epidemiology in Canada. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews guideline was used. Literature searches were conducted in six databases and in gray literature. The epidemiology of orthobunyaviruses was characterized for studies focusing on host species, including spatiotemporal patterns, risk factors, and climate change impact. Results: A total of 172 relevant studies were identified from 1734 citations from which 95 addressed host species, including humans, wildlife, and domestic animals including livestock. The orthobunyaviruses-Cache Valley virus (CVV), Jamestown Canyon virus (JCV), Snowshoe Hare virus (SHV), and La Crosse virus (LACV)-were identified, and prevalence was widespread across vertebrate species. CVV, JCV, and SHV were detected across Canada and the United States. LACV was reported only in the United States, predominantly the Mid-Atlantic and Appalachian regions. Disease varied by orthobunyavirus and was associated with age, environment, preexisting compromised immune systems, or livestock breeding schedule. Conclusion: Knowledge gaps included seroprevalence data in Canada, risk factor analyses, particularly for livestock, and disease projections in the context of climate change. Additional surveillance and mitigation strategies, especially accounting for climate change, are needed to guide future public health efforts to prevent orthobunyavirus exposure and disease.

Estimating spatial and temporal trends of dog importation into Canada from 2013 to 2019.

Background and objective: For several years, there has been growing concern over the public and animal health impacts of dog importation, with many Canadian veterinarians reporting increasing diagnoses of exotic pests and pathogens. This study is the first to estimate the number of dogs imported into Canada and describe spatial and temporal trends. Animal and procedure: Commercial and a subset of personal dog importation records, obtained from the Canada Border Services Agency, were used to estimate the total number of dogs imported into Canada from 2013 to 2019. Results: The number of dogs imported annually increased by > 400% over the study period, with > 37 000 dogs imported in 2019. The majority of dogs (72%) were imported from the United States and Eastern Europe, and 23% originated in a country considered high-risk for canine rabies. Conclusion: Dog importation into Canada has increased substantially over time. Moving forward, education and improved tracking will be essential.

Estimation des tendances spatiales et temporelles de l'importation de chiens au Canada de 2013 à 2019. Contexte et objectif: Depuis plusieurs années, les impacts de l'importation de chiens sur la santé publique et animale suscitent de plus en plus d'inquiétudes, de nombreux vétérinaires canadiens signalant une augmentation des diagnostics de vermines et d'agents pathogènes exotiques. Cette étude est la première à estimer le nombre de chiens importés au Canada et à décrire les tendances spatiales et temporelles. Animal et procédure: Des dossiers d'importation de chiens commerciaux et personnels, obtenus auprès de l'Agence des services frontaliers du Canada, ont été utilisés pour estimer le nombre total de chiens importés au Canada de 2013 à 2019. Résultats: Le nombre de chiens importés chaque année a augmenté de > 400 % au cours de la période d'étude, avec > 37 000 chiens importés en 2019. La majorité des chiens (72 %) ont été importés des États-Unis et d'Europe de l'Est, et 23 % sont originaires d'un pays considéré comme à haut risque de rage canine. Conclusion: L'importation de chiens au Canada a considérablement augmenté au fil du temps. À l'avenir, l'éducation et un meilleur suivi seront essentiels.(Traduit par Dr Serge Messier).

Epidemiology and clinical manifestations of reported Lyme disease cases: Data from the Canadian Lyme disease enhanced surveillance system.

Lyme disease cases reported in seven Canadian provinces from 2009 to 2019 through the Lyme Disease Enhanced Surveillance System are described herein by demographic, geography, time and season. The proportion of males was greater than females. Bimodal peaks in incidence were observed in children and older adults (≥60 years of age) for all clinical signs except cardiac manifestations, which were more evenly distributed across age groups. Proportions of disease stages varied between provinces: Atlantic provinces reported mainly early Lyme disease, while Ontario reported equal proportions of early and late-stage Lyme disease. Early Lyme disease cases were mainly reported between May through November, whereas late Lyme disease were reported in December through April. Increased awareness over time may have contributed to a decrease in the proportion of cases reporting late disseminated Lyme disease. These analyses help better describe clinical features of reported Lyme disease cases in Canada.

Cache a Killer: Cache Valley virus seropositivity and associated farm management risk factors in sheep in Ontario, Canada.

Cache Valley virus (CVV) disease is a mosquito-borne zoonosis endemic to North America. CVV disease is reported most often in sheep, causing lethal congenital deformities. There are limited data on CVV in Ontario, which is the largest sheep producing province in Canada. This study aimed to determine CVV seroprevalence in Ontario sheep flocks and investigate farm management factors associated with CVV exposure. A cross-sectional study was performed including 364 mature ewes across 18 farms selected from the five largest sheep districts in the province. A questionnaire was administered at each farm to determine farm management practices pertinent to the flock and ewes specifically sampled. Mixed multivariable logistic regression with a random effect for farm was conducted to assess associations between CVV seropositivity (outcome variable) and farm management risk factors (predictor variables). CVV seroprevalence was 33.2% in individual ewes (95% CI: 28.4%-38.1%) as determined by a virus neutralization assay with a titre > 4. Sixteen of the eighteen flocks (88.9%) had at least one CVV seropositive ewe. Increased age, smaller flock size, and sheep housing near wetlands, lakes, or ponds were found to be significantly associated with higher odds of CVV seropositivity. These findings are valuable in guiding breeding practices and housing during mosquito season to minimize infection and, ultimately, CVV disease in the flock.

Dog caregivers' perceptions, motivations, and behaviours for feeding treats: A cross sectional study.

Treats are commonly fed by most dog caregivers and can constitute a significant proportion of a dog's diet, potentially contributing to obesity. Feeding aspects related to treats specifically, remain underexplored. An e-survey was voluntarily completed by 716 dog caregivers predominantly from Canada and the USA to identify and describe caregivers' perceptions, motivations, and behaviours surrounding treats, and factors that influence decisions about feeding treats. Survey responses were analyzed using descriptive statistics, chi-square tests, Kruskal-Wallis one-way ANOVA, and Wilcoxon signed-rank tests. Multivariable logistic regression analyses were performed to analyze (1) measurement methods associated with monitoring treat intake, and (2) frequency of feeding different types of treats with perceiving dog as overweight/obese. Most caregivers considered the term 'treat' in a nutritional context, but respondents expressed mixed perceptions of how they consider treats in relation to their dog's primary diet. Alongside training and sports activities, aspects relating to the human-animal bond were highly reported to influence decisions surrounding treats. Most respondents were motivated to provide treats because it makes their pet happy, and to strengthen the bond with their dog, and nearly 40% of caregivers frequently feed treats to show love to their dog. Human food and table scraps were frequently fed by 30-40% of caregivers and feeding human food weekly was predictive of caregivers perceiving their dog to be overweight/obese (OR=2.24, p = 0.007). Caregivers estimated treats to account for a median of 15% of their dog's total diet, based on estimated quantity. Caregivers who reported using a measuring cup/scoop to measure their dog's treats were more likely to monitor their dog's treat intake (OR=3.38, p = 0.002). Most caregivers monitor their dog's body condition (60%) or consider their dog's recent activity level (43%) to decide on the amount of treats to feed; only 22% of caregivers reported veterinary advice to support their decisions on the amount of treats to feed. Findings from this research offer new insights to dog caregiver feeding habits and their perceptions of treats in relation to the canine diet. These results can be used to inform veterinary counselling strategies and caregiver education initiatives to promote animal health and well-being.

Isolation and multilocus sequence typing of Borrelia burgdorferi from Ixodes scapularis collected from dogs in Ontario, Canada.

OBJECTIVE: To identify the multilocus sequence typing (MLST) sequence types of Borrelia burgdorferi from Ixodes scapularis in Ontario, Canada. RESULTS: One hundred and eighty-five I. scapularis ticks were submitted from 134 dogs via participating clinics from April 1, 2019, to March 31, 2020. Seventeen MLST sequence types of B. burgdorferi were detected from fifty-eight cultured isolates from 21 ticks. The most common MLST sequence types were 12 and 16. Mixed infections of two MLST sequence types were detected in four ticks. Three sequence types (48, 317, 639) were new detections in Ontario.

Infestation patterns of Ixodes scapularis and Dermacentor variabilis on dogs and cats across Canada.

Due to recent climatic and land use changes, Canada has experienced changes in tick populations, leading to an increased risk of tick bites and tick-borne pathogen exposure, especially in eastern Canada. Preventative recommendations for companion animals from veterinary professionals include regular use of tick prevention products and tick checks. Tick checks, specifically, should target regions of an animal's body which are deemed to be high risk for tick attachment. However, tick species-specific infestation patterns on dogs and cats are largely understudied, and additional research is needed to help guide targeted tick checks. The objective of this study was to identify tick species-specific infestation patterns on dogs and cats. Ticks were collected for one year (April 2019 -March 2020) from 94 veterinary clinics across Canada as part of the Canadian Pet Tick Survey. All ticks were identified to species, and data on the location of tick attachment were ascertained with each submission. To examine the association between location of attachment (outcome) and tick species (explanatory variable), specifically Ixodes scapularis and Dermacentor variabilis, mixed effects univariable models were built. Two thousand three hundred and six submissions were received from 1925 dogs and 381 cats across Canada. Of these submissions, 1377 comprised Ixodes scapularis, and 620 comprised Dermacentor variabilis. Clear tick species-specific infestation patterns for dogs were present, with I. scapularis being significantly more likely to be found on the shoulders, and D. variabilis more likely to be found on the ears and neck. Dermacentor variabilis was more likely to be found on the cranial aspect of cats' limbs, compared to I. scapularis. Up-to-date information on infestation patterns can be used to inform veterinary professionals and pet owners of common attachment sites based on established ticks in their region and thus conduct targeted tick checks.

Transformative learning for a sustainable and healthy future through ecosystem approaches to health: insights from 15 years of co-designed ecohealth teaching and learning experiences.

This paper presents insights from the work of the Canadian Community of Practice in Ecosystem Approaches to Health (CoPEH-Canada) and 15 years (2008-2022) of land-based, transdisciplinary, learner-centred, transformative learning and training. We have oriented our learning approaches to Head, Hands, and Heart, which symbolise cognitive, psychomotor, and affective learning, respectively. Psychomotor and affective learning are necessary to grapple with and enact far-reaching structural changes (eg, decolonisation) needed to rekindle healthier, reciprocal relationships with nature and each other. We acknowledge that these approaches have been long understood by Indigenous colleagues and communities. We have developed a suite of teaching techniques and resources through an iterative and evolving pedagogy based on participatory approaches and operating reciprocal, research-pedagogical cycles; integrated different approaches and ways of knowing into our pedagogy; and built a networked Community of Practice for continued learning. Planetary health has become a dominant framing for health-ecosystem interactions. This Viewpoint underscores the depth of existing scholarship, collaboration, and pedagogical expertise in ecohealth teaching and learning that can inform planetary health education approaches.

Student Veterinarian Perceptions of Community-Based Primary Care Veterinary Clinics in Indigenous Communities in Southern Ontario, Canada.

Community-based primary care veterinary clinics represent an opportunity to benefit multiple populations. Student veterinarians are afforded the opportunity to build technical and non-technical professional skills, while underserved communities are provided with access to companion animal care. The Ontario Veterinary College (OVC), as with many other veterinary colleges across Canada and the United States, has hosted community-based primary care veterinary clinics, including in local Indigenous communities. As these clinics continue and grow, it is critical to evaluate their operation to ensure that they align with community goals and values, adequately support student learning, and do not perpetuate racism and implicit bias. The objective of this study was to explore the perceptions of student veterinarians who had volunteered at community-based primary care veterinary clinics in First Nations communities in southern Ontario, Canada. We used an online survey that consisted of multiple choice and short answer questions focused on motivating factors for involvement, supports available before and during the clinics, exposure to Indigenous cultures, and the challenges and rewards associated with volunteering. Forty-one student veterinarians from OVC completed the survey in January 2020. Most students were motivated to volunteer to make a positive difference in the lives of people and animals and improve their clinical skills. In general, respondents felt adequately prepared for and supported during their experiences but did recommend additional pre-departure instructions on roles and responsibilities. Participants were ambivalent as to whether they had learned about Indigenous culture, with several strongly recommending more cultural sensitivity training. Most students found their experiences rewarding because of the gratitude expressed by clients and the feeling that they had made a difference. We reflect on the potential benefits and challenges of community-based primary care veterinary clinics in light of student responses.

Comparing Canadian Lyme disease risk area classification methodologies.

Lyme disease risk areas have increased across Canada in recent decades with the ongoing range expansion of Ixodes scapularis and Borrelia burgdorferi. Different methodologies are used by federal and provincial governments to determine local Lyme disease risk, which can make comparisons between regions challenging. In this study, seven Canadian Lyme disease risk classification methodologies were compared with each other to highlight the strengths and limitations of how each definition measured I. scapularis and B. burgdorferi risk. Each methodology was applied to active surveillance data from Ontario, and per cent agreement and kappa statistics were calculated. The methodologies varied in their measurements of the risk of exposure to I. scapularis and B. burgdorferi based on their use of active surveillance techniques, multiple types of collected surveillance data and laboratory confirmation of B. burgdorferi. Most initial Lyme disease risk site classifications were maintained over time. Kappa and per cent agreement statistics highlighted large differences between 8 of the 15 methodology pairings, indicating the presence of inconsistencies between most methodologies. Accurate, consistent surveillance and assessment of the spread of I. scapularis and its pathogens will aid with communicating Lyme disease risk to the public and preventing tick-borne pathogen transmission.

Assessing the spatial and temporal patterns and risk factors for acquisition of Ixodes spp. by companion animals across Canada.

Climatic and land use changes have contributed to substantial changes in the abundance, distribution, and activity patterns of ticks in Canada, which have led to an increased risk of tick bites and tick-borne pathogen exposure for companion animals. The objectives of this study were to describe current spatial and temporal patterns of Ixodes spp. on companion animals in Canada and explore the association between tick bites and dog and cat demographic factors. Ticks were collected for one year (April 2019 - March 2020) from 94 veterinary clinics. Included with each submission was a short questionnaire containing owner-reported information on travel history, date of removal and suspected location of tick acquisition, and animal-specific demographic factors. Ticks were identified morphologically using a stereomicroscope, standard keys, and through PCR analyses. Mixed effect multivariable logistic regression models were built to explore the association between an Ixodes scapularis bite and animal demographic factors; veterinary clinic was included as a random effect. Approximately 2300 submissions were received from clinics across Canada, totalling 4425 ticks. The most common Ixodes spp. was I. scapularis (n = 2168), followed by Ixodes pacificus (n = 172) and Ixodes cookei (n = 155). Ixodes scapularis were well distributed in regions across central and eastern Canada. Ixodes cookei was found in eastern Canada, with the greatest numbers from Quebec and New Brunswick. Ixodes pacificus submissions were restricted to British Columbia. Across eastern Canada, dogs of the herding, mixed breed (large and small), sporting, working, terrier, and toy breed groups, and spayed cats were all found to have higher odds of acquiring I. scapularis, compared to other tick species. For the dog model, significant interactions were found between predictor variables age and sex. Regional information on tick distribution, seasonality, and risk factors for acquisition contribute to evidence-based veterinary practices for tick and tick-borne disease control in Canada.

Spatial patterns of Borrelia burgdorferi, Borrelia miyamotoi and Anaplasma phagocytophilum detected in Ixodes spp. ticks from Canadian companion animals, 2019-2020.

Increasing temperatures due to climate change have contributed to a northward range expansion of Ixodes scapularis ticks in Canada. These ticks harbour pathogens of public and animal health significance, including Borrelia burgdorferi and Anaplasma phagocytophilum, which cause Lyme disease and anaplasmosis, respectively, in humans, dogs and horses, and Borrelia miyamotoi, which causes a flu-like relapsing fever in humans. To address the risks associated with these vector-borne zoonotic diseases, continuous tick surveillance is advised. This study examined spatial patterns of B. burgdorferi, B. miyamotoi and A. phagocytophilum from ticks submitted through a national study on ticks of companion animals. From 1 April 2019 to 31 March 2020, we received a total of 1541 eligible submissions from 94 veterinary clinics across Canada. Individual and pooled samples of a maximum of either 5 I. scapularis, I. pacificus or I. angustus samples from the same animal and of the same life stage were screened using real-time PCR targeting genes 23S rRNA for Borrelia spp. and msp2 for A. phagocytophilum. Confirmatory testing was conducted on all 23S rRNA positive samples using a duplex assay for ospA and flaB to differentiate B. burgdorferi and B. miyamotoi, respectively. Prevalence estimates were highest (>20%) for B. burgdorferi in southwestern Manitoba, eastern Ontario, southwestern Quebec, New Brunswick and Nova Scotia. Estimates of B. miyamotoi and A. phagocytophilum were much lower (<5%), except for higher A. phagocytophilum (>5%) estimates for southern Manitoba, eastern Ontario and Prince Edward Island. Findings from this study, combined with other surveillance approaches, can be used to guide veterinary and public health approaches for ticks and tick-borne diseases.

Range Expansion of Ixodes scapularis and Borrelia burgdorferi in Ontario, Canada, from 2017 to 2019.

Range expansion of the vector tick species, Ixodes scapularis, has been detected in Ontario over the last two decades. This has led to elevated risk of exposure to Borrelia burgdorferi, the bacterium that causes Lyme disease. Previous research using passive surveillance data suggests that I. scapularis populations establish before the establishment of B. burgdorferi transmission cycles, with a delay of ∼5 years. The objectives of this research were to examine spatial and temporal patterns of I. scapularis and its pathogens from 2017 to 2019 in southwestern, eastern, and central Ontario, and to explore patterns of B. burgdorferi invasion. Over the 3-year study period, drag sampling was conducted at 48 sites across Ontario. I. scapularis ticks were tested for B. burgdorferi, Borrelia miyamotoi, Anaplasma phagocytophilum, and Babesia species, including Babesia microti and Babesia odocoilei, and Powassan virus. I. scapularis was detected at 30 sites overall, 22 of which had no history of previous tick detection. B. burgdorferi was detected at nine sites, eight of which tested positive for the first time during this study and five of which had B. burgdorferi detected concurrently with initial tick detection. Tick and pathogen hotspots were identified in eastern Ontario in 2017 and 2018, respectively. These findings provide additional evidence on the range expansion and population establishment of I. scapularis in Ontario and help generate hypotheses on the invasion of B. burgdorferi in Ontario. Ongoing public health surveillance is critical to monitor changes in I. scapularis and its pathogens in Ontario.

The utility of a maximum entropy species distribution model for Ixodes scapularis in predicting the public health risk of Lyme disease in Ontario, Canada.

Lyme disease is an emerging public health threat in Ontario, Canada due to ongoing range expansion of the tick vector, Ixodes scapularis. Tick density is an important predictor of human Lyme disease risk and is typically measured using active tick surveillance via drag sampling, which is time and resource-intensive. New cost-effective tools are needed to augment current surveillance activities. Our objective was to evaluate the ability of a maximum entropy (Maxent) species distribution model to predict I. scapularis density in three regions of Ontario - Ottawa, Kingston, and southern Ontario - in order to determine its utility in predicting the public health risk of Lyme disease. Ticks were collected via drag sampling at 60 sites across the three regions. Model-predicted habitat suitability was calculated from a previously constructed Maxent model as the mean predicted habitat suitability within a 1-km radius of each site. Spearman's correlation coefficient was used to quantify the continuous relationship between model-predicted habitat suitability and tick density, and negative binomial regression was used to quantify the relationship between tick density and model-predicated habitat suitability. Spearman's correlation coefficients for the full study area, Kingston region, and Ottawa region were 0.517, 0.707, and 0.537, respectively, indicating a moderate positive relationship and ability of the model to predict tick density. Regression analysis further demonstrated a significant positive association between tick density and model-predicted habitat suitability (p< 0.001). Using a dichotomized measure of model-predicted habitat suitability, the incidence rate ratio - the ratio of ticks per m2 in sites predicted to have a 'suitable' habitat compared to those predicted to have 'not suitable' habitat - was 33.95, indicating that tick density was significantly higher at sites situated in areas with predicted suitable habitat. Given that tick density is an important component of Lyme disease risk, the ability to predict high tick density locations using the Maxent model may make it a cost-effective tool for identifying geographic areas that pose elevated public health risk of Lyme disease.

Evaluation of 2 ELISAs to determine Borrelia burgdorferi seropositivity in horses over a 12-month period.

The blacklegged tick (Ixodes scapularis), which transmits Borrelia burgdorferi, the causative agent of Lyme disease, has undergone rapid range expansion in Ontario. In horses, Lyme disease remains an enigmatic disease, with limited understanding of the pathogenesis and many issues pertaining to selection and interpretation of laboratory tests. We evaluated B. burgdorferi seropositivity in naturally exposed horses over a 12-mo period and compared paired samples with 2 common serologic tests. Serum samples were collected in 2017, ~1 y after initial testing, from a cohort of 22 horses that were seropositive in a 2016 seroprevalence study. Samples were tested using a C6 ELISA and a multiplex ELISA targeting outer surface proteins A, C, and F. 1 y after initial testing, 14 of 22 (64%) horses remained seropositive; 7 (32%) were positive on the multiplex ELISA, 2 (9%) on C6 ELISA, and 5 (23%) on both tests. Repeatability was 100% for the C6 ELISA, and 95% for the multiplex ELISA, with no significant difference between paired sample multiplex titer values. Our results indicate strong intra-test reliability, although further investigation is required to determine the clinical significance of serologic testing.