CANINE DISTEMPER VIRUS ECOLOGY: INSIGHTS FROM A LONGITUDINAL SEROLOGIC STUDY IN WILD RACCOONS (PROCYON LOTOR).

Increasing reports of canine distemper virus (CDV) in a variety of hosts, and changing CDV dynamics, have led to renewed interest in the ecology of CDV infections in wildlife. Longitudinal serologic studies provide insights into intrapopulation and intraindividual pathogen dynamics, but few studies in wildlife have been conducted. We used data from 235 raccoons (Procyon lotor) captured on more than one occasion between May 2011 and November 2013 to investigate CDV dynamics in Ontario, Canada. Using mixed multivariable logistic regression, we found that juvenile raccoons were more likely to be seronegative from August to November than from May to July. Using paired titers from CDV-exposed individual raccoons, we determined that the winter breeding season, when there is high intraspecific contact and an increase in susceptible juveniles, may be a period of high risk for CDV exposure. Interestingly, CDV seropositive adult raccoons had nondetectable titers ranging from 1 mo to 1 yr later. Based on our preliminary investigation using two different statistical approaches, CDV exposure was associated with a decrease in parvovirus titer. This result raises important questions about whether virus-induced immune amnesia occurs after CDV exposure, which has been described for measles virus, a closely related pathogen. Overall, our results provide significant insights into CDV dynamics. Further research is needed to investigate whether CDV-induced immune amnesia occurs in raccoons and to determine the potential impacts of a reduced population immunity that may occur secondary to CDV exposure, particularly as it relates to rabies control efforts.

Characterization of neurotropic HPAI H5N1 viruses with novel genome constellations and mammalian adaptive mutations in free-living mesocarnivores in Canada.

The GsGd lineage (A/goose/Guangdong/1/1996) H5N1 virus was introduced to Canada in 2021/2022 through the Atlantic and East Asia-Australasia/Pacific flyways by migratory birds. This was followed by unprecedented outbreaks affecting domestic and wild birds, with spillover into other animals. Here, we report sporadic cases of H5N1 in 40 free-living mesocarnivore species such as red foxes, striped skunks, and mink in Canada. The clinical presentations of the disease in mesocarnivores were consistent with central nervous system infection. This was supported by the presence of microscopic lesions and the presence of abundant IAV antigen by immunohistochemistry. Some red foxes that survived clinical infection developed anti-H5N1 antibodies. Phylogenetically, the H5N1 viruses from the mesocarnivore species belonged to clade 2.3.4.4b and had four different genome constellation patterns. The first group of viruses had wholly Eurasian (EA) genome segments. The other three groups were reassortant viruses containing genome segments derived from both North American (NAm) and EA influenza A viruses. Almost 17 percent of the H5N1 viruses had mammalian adaptive mutations (E627 K, E627V and D701N) in the polymerase basic protein 2 (PB2) subunit of the RNA polymerase complex. Other mutations that may favour adaptation to mammalian hosts were also present in other internal gene segments. The detection of these critical mutations in a large number of mammals within short duration after virus introduction inevitably highlights the need for continually monitoring and assessing mammalian-origin H5N1 clade 2.3.4.4b viruses for adaptive mutations, which potentially can facilitate virus replication, horizontal transmission and posing pandemic risks for humans.

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.

USING WILDLIFE REHABILITATION AND POSTMORTEM DATA TO IDENTIFY KEY CAUSES OF MORBIDITY AND MORTALITY IMPACTING THE HEALTH AND WELFARE OF FREE-LIVING WILD ANIMALS IN CANADA.

The health and welfare of wild animals are of increasing concern, yet there are very few large-scale data syntheses examining how causes of wildlife morbidity and mortality vary across time, space, and taxa. Records for 18,540 animals submitted to the Canadian Wildlife Health Cooperative (CWHC) (2009-19) and 144,846 animals admitted to 19 wildlife rehabilitation centers (WRCs) (2015-19) were evaluated to 1) identify the main causes of morbidity and mortality for Canadian wildlife and 2) assess the utility and complementarity of these two data sources to further our understanding of wildlife health. The CWHC cases (mortality) were examined by pathologists and grouped by the presence or absence of five diagnostic categories: trauma, emaciation, infection or inflammation, toxicity, and other. These CWHC animals were also classified as "killed due to real or perceived human-wildlife conflict" based on finder history. The WRC admissions were categorized by health issue (according to intake records) and based on reported or observed situational reasons for admission: parental loss, unsafe or unsuitable location, nest or habitat disturbance, illegal possession, and abnormal behavior. For both datasets, the main reason for submission or admission was trauma (44 and 48%, respectively), especially vehicle collisions (7 and 11%) and window or building strikes (5 and 7%). Many other WRC admissions were due to parental loss (28%), cat attacks (6%), and immature animals being found in unsafe or unsuitable locations (6%). Most other CWHC mortalities were caused by infections (27%) and emaciation (23%). Relatively few birds, amphibians, and reptiles submitted to CWHC were killed due to human-wildlife conflict, but 22% of mammals were killed for this reason, highlighting the taxonomic differences in the perceived threat of wildlife to finders, and therefore their response. Together, these data sources highlight key issues impacting the health and welfare of wild animals in Canada.

Behavior and adoptability of hoarded cats admitted to an animal shelter.

OBJECTIVES: The aim of this study was to analyze the behavioral characteristics and success of adoption for previously hoarded cats. METHODS: Shelter records and post-adoption surveys were analyzed for hoarded cats ⩾6 months old at intake. A non-standard scoring system was used. Intake scores were allocated contemporaneously and socialization scores were applied retrospectively for three time points (TPs): 5-10 days post-intake (shelter TP), ⩽1 week post-adoption (home TP1) and >1 week post-adoption (home TP2). Adoption returns were compared between hoarded and non-hoarded cats. RESULTS: The study included 195 hoarded cats, of which 174 were adopted. Of 164 cats with intake scores, 86 (52%) were scored as 'friendly' at intake. Forty-five cats had socialization scores for all of the TPs, and of these, the percentages of 'supersocial' or 'social' decreased from 87% at the shelter TP to 47% at home TP1, then increased to 84% at home TP2. Most cats that scored as 'tense' at intake had supersocial or social scores at home TP2. Nine of the 88 cats with survey results had out-of-box (OOB) elimination in either the shelter or home but only 1/88 in both. Adopters expressed positive feelings for 42/43 cats for which feelings-based language was used in their survey responses. Notable behaviors, such as neediness, were recorded for 48/88 cats. Relationships with other household pets were typically positive. Eighteen of 174 hoarded (10%) and 188/2662 non-hoarded (7.1%) cats were returned post-adoption. Of these, six hoarded and 87 non-hoarded returns included behavioral reasons. There were no significant differences between hoarded and non-hoarded cats for total or behavioral returns. CONCLUSIONS AND RELEVANCE: Hoarded cats had high adoption rates, high adopter satisfaction and the potential for good emotional well-being in adoptive homes. Behavior at intake and OOB elimination in the shelter may not reflect post-adoption behavior. Behavior-based outcome decisions for these vulnerable animals should be deferred to allow time for habituation.

Genetic characterization of canine distemper virus from wild and domestic animal submissions to diagnostic facilities in Canada.

Traditionally considered an agent affecting domestic dogs, canine distemper virus (CDV) is now well known for an ability to infect a broad range of hosts. In Ontario, domestic dogs are routinely vaccinated and clinical disease attributed to CDV infection in this population is infrequent. CDV has been regularly documented in Ontario wildlife spanning at least 4 decades however, the molecular identity of circulating CDV strains is currently unknown. Our objective was to investigate the molecular identities of and genetic relationships between CDV detected in wild and domestic animals from Canada, across multiple host species and over time. Samples were opportunistically collected from submissions to the Ontario-Nunavut node of the Canadian Wildlife Health Cooperative and the Animal Health Laboratory in Guelph, Ontario. RT-PCR was used to confirm CDV diagnosis, and the hemagglutinin gene was sequenced. Phylogenetic relationships were inferred, and the geographic distribution of clades was visualized using a geographic information system. Phenetic relationships between sequences were investigated with a median joining network analysis and through mixed multivariable linear regression. CDV sequences from ten wild and domestic species were characterized into seven lineages, that overlapped geographically and temporally. The predominant lineage circulating in Ontario wildlife, denoted Canada-1, has not been previously described to the authors knowledge. Our analysis indicates that the Canada-1 lineage is most genetically similar to America-1 sequences, however according to current methodology represents a distinct lineage. Multiple co-circulating CDV lineages were also identified, and raccoons appear to play an important role in the maintenance and transmission of these heterogeneous lineages in Ontario. This study also confirmed the presence of CDV from a lineage not found to be circulating in Ontario wildlife, in a domestic dog imported into Ontario from South America. Therefore, travel and the trade of animals may be an important avenue for the introduction of novel CDV lineages. It remains unclear whether and to what extent the genetic heterogeneity identified poses a risk to the efficacy of current vaccines. Increasing viral activity and continued antigenic drift resulting in partial protection or vaccine failure remains a concern.

Fecal viral DNA shedding following clinical panleukopenia virus infection in shelter kittens: a prospective, observational study.

OBJECTIVES: The aims of this study were to determine the magnitude and duration of fecal viral DNA shedding after diagnosis of feline panleukopenia (FP) in a group of shelter cats using quantitative real-time PCR (qPCR); to assess the utility of a negative point-of-care test or the resolution of diarrhea and systemic signs as proxy measures for qPCR positivity; and to investigate patterns of additional enteric pathogens in relation to feline panleukopenia viral shedding duration. METHODS: Feline panleukopenia virus (FPV) infection in clinically affected shelter cats was confirmed by a commercial qPCR test. Observations were made on days 0, 3, 7, 14 and 21 post-diagnosis. Fecal flotation, FPV qPCR and the canine parvovirus IDEXX SNAP Parvo ELISA (SNAP) test were performed on fecal samples. RESULTS: Forty cats and kittens with confirmed panleukopenia were initially enrolled. Sixteen kittens were sampled until day 14, and 12 were followed to day 21. Median DNA viral copy numbers fell below the diagnostic cut-off by day 7, with 13/16, 6/16, 1/16 and 0/12 testing PCR-positive on days 3, 7, 14 and 21, respectively. The SNAP test was positive in 12/16 kittens on day 0 and only 3/16 on day 3. SNAP test results, diarrhea and systemic signs were inconsistent in relation to qPCR positivity post-diagnosis. Additional enteric pathogens were common. The presence of additional pathogen types was suggestive of a longer PCR shedding duration, but this was not tested statistically owing to the small sample size. CONCLUSIONS AND RELEVANCE: These findings suggest that cats should be isolated for at least 14 days after a diagnosis of FP, but that release from isolation after this point is reasonable, in association with a multifaceted infection control strategy. The study findings did not support using SNAP test results, diarrhea or systemic signs as proxy measures for virus shedding.

Diagnostic testing for feline panleukopenia in a shelter setting: a prospective, observational study.

OBJECTIVES: The aim of this study was to optimize the diagnosis of feline panleukopenia virus (FPV) infection in a shelter setting by: (1) comparing the results of the canine parvovirus IDEXX SNAP Parvo (SNAP) point-of-care ELISA with a commercial FPV quantitative real-time PCR (qPCR) test; (2) assessing whether vomit and anal/rectal swabs could be used for early diagnosis; and (3) clarifying the interpretation of weak-positive SNAP test results. METHODS: The study included shelter cats and kittens with incomplete or unknown vaccination history that had clinical signs suspicious for feline panleukopenia and fecal SNAP and PCR tests performed within 24 h of onset. Feces, anal/rectal swabs and vomit were tested using SNAP and PCR, with fecal PCR utilized as the reference standard. RESULTS: One hundred and forty-five cats were included. Seventeen were diagnosed with FPV infection and 62 were negative; 66 could not be individually designated because they were co-housed. Sensitivity was as follows: fecal SNAP 55% (n = 102; 95% confidence interval [CI] 32-77); swab SNAP 30% (n = 55; 95% CI 7-65); swab PCR 77% (n = 55; 95% CI 46-95); and vomit PCR 100% (n = 17; 95% CI 16-100). Specificity was high (96-100%) for all sample and test types. For PCR-positive fecal samples, true-positive SNAP tests (including weak positives) had significantly higher DNA viral copy numbers than false-negative SNAP tests (P = 0.0031). CONCLUSIONS AND RELEVANCE: The SNAP ELISA should be viewed as an initial diagnostic test to rule in feline panleukopenia. Positive fecal SNAP test results, including weak positives, are highly likely to be true positives in clinically affected animals. Negative results in clinically affected animals are unreliable and should be followed up with PCR testing.

COMPARISON OF TWO SURVEILLANCE COMPONENTS FOR INVESTIGATING THE EPIDEMIOLOGY OF CANINE DISTEMPER VIRUS IN RACCOONS (PROCYON LOTOR).

Canine distemper virus (CDV) has a broad mammalian host range. In Ontario, Canada, CDV is frequently encountered in wild carnivores and is the most common infectious cause of death for raccoons (Procyon lotor). The isolation of wild-type CDV strains genetically distinct from vaccine strains in North America has renewed interest in the epidemiological patterns of this virus. However, wildlife surveillance is challenging and often utilizes a combination of surveillance methods with aggregation of data from multiple sources. Our objective was to compare raccoon CDV data generated through two separate surveillance components operated by the Ontario-Nunavut node of the Canadian Wildlife Health Cooperative. The raw data generated by each component in addition to the results of multilevel logistic regression and spatial scan statistics, were compared between the datasets. A total of 498 raccoons obtained via passive surveillance between 2007 and 2017 and 887 raccoons obtained via enhanced-passive surveillance between 2014 and 2017, were tested for CDV. The number and geographic distribution of reports, proportion of yearly reports classified as CDV-positive, and characteristics of CDV-positive raccoons differed between passive and enhanced-passive surveillance components. Geographical data demonstrated that CDV infection was present throughout southern Ontario. The geographic area of both surveillance components combined was more representative than either passive or enhanced-passive surveillance in isolation; but was restricted compared to the overall distribution of raccoons in Ontario. Regression analyses produced statistically significant associations between the presence of CDV and host and environmental variables that were at times discordant between the two datasets. Studying the properties of these datasets will inform future passive wildlife surveillance strategies and highlights the impact that a surveillance strategy can have on the results of epidemiological analyses.

Medical conditions and outcomes in 371 hoarded cats from 14 sources: a retrospective study (2011-2014).

OBJECTIVES: The aims of this study were to: (1) describe the source, route of surrender and signalment of hoarded cats relinquished to the Toronto Humane Society (THS); (2) document the prevalence of medical conditions by group (place of origin); (3) compare medical conditions between institutional hoarding (IH) and non-institutional hoarding (NIH) environments; and (4) report length of stay (LOS) and outcomes in hoarded and non-hoarded cats. METHODS: A retrospective, descriptive epidemiological study was performed using THS records from between July 2011 and June 2014. The prevalence of medical conditions was calculated for the different groups. Univariable logistic regression with a random intercept to account for autocorrelation among animals from the same group was used to examine the influence of IH and NIH environments on selected medical conditions. LOS and outcomes were calculated for hoarded and non-hoarded cats. RESULTS: Three hundred and seventy-one hoarded cats from 14 sources were included. The majority (n = 352/371) were surrendered voluntarily, many with the assistance of a community intermediary. Upper respiratory infection (URI) was the most common medical condition (38% of cats), followed by dermatological disease (30%). The prevalence of medical conditions varied substantially between groups. The odds of URI at intake (odds ratio [OR] 4.35, P = 0.044) and chronic URI (OR 23.70, P <0.0001) were significantly greater for IH compared with NIH. Adoption rates, euthanasia rates and LOS were similar for hoarded and non-hoarded cats. CONCLUSIONS AND RELEVANCE: The different prevalence of medical conditions in groups of hoarded cats indicates a continuum of harm and severity in animal hoarding. Hoarded cats can have LOS and live release rates comparable with non-hoarded cats. Cats from IH were significantly more likely to have chronic URI. This study highlights the need for a greater focus on IH, as well as the role of community intermediaries and the potential for a harm reduction approach to animal hoarding.

Ventriculoperitoneal shunt for treatment of hydrocephalus in a French bulldog puppy.

A 6.5-week-old bulldog was presented with lethargy, anorexia, and stunted growth. A domed skull, ventrolateral strabismus, hypermetria, and delayed hopping were observed. Congenital hydrocephalus was diagnosed and a ventriculoperitoneal shunt was placed. After surgery, a shunt obstruction occurred but resolved with treatment. The puppy responded well and neurological deficits continued to improve after surgery.

Dérivation ventriculo-péritonéale pour le traitement de l'hydrocéphalie chez un chiot Bouledogue français. Un Bouledogue âgé de 6,5 semaines a été présenté pour de l'abattement, de l'anorexie et une croissance retardée. Un crâne en forme de dôme, du strabisme ventrolatéral, de l'hypermétrie et du sautillement retardé ont été observés. Une hydrocéphalie congénitale a été diagnostiquée et une dérivation ventriculo-péritonéale a été placée. Après la chirurgie, une obstruction de la dérivation s'est produite mais s'est résorbée après un traitement. Le chiot a bien répondu et les déficits neurologiques ont continué de s'améliorer après la chirurgie.(Traduit par Isabelle Vallières).