Canine Distemper Virus: Ecology, Epidemiology and Addressing Challenges in the Wider Wildlife Health Surveillance Context
Notice bibliographique
Résumé
This thesis was both an investigation into the ecology of canine distemper virus (CDV) in Ontario wildlife, and an opportunity to use a CDV lens to explore challenges and opportunities associated with the ways in which we learn about wildlife health and disease in Canada. While canine distemper is considered endemic in Ontario raccoons, information on the epidemiology of this important virus is scarce and the genetic identity of circulating variants is unknown. Based on an analysis of a longitudinal serological raccoon data set obtained through a targeted study in southern Ontario, I report that the winter breeding period was a period of high risk of CDV exposure. Furthermore, it was apparent that many wild raccoons survive for extended periods of time after exposure to CDV and that adult raccoons can revert from seropositive on one capture to having a non-detectable titre at a subsequent capture(s). Based on reports of immune amnesia following infection with measles virus (a similar pathogen), it is noteworthy that CDV exposure may be associated with a decrease in parvovirus titre. Using a multi-species dataset of opportunistically collected wildlife, the genetic identities of and genetic relationships between circulating CDV variants were explored. Multiple co-circulating variants were identified including a novel but dominant variant, named Canada-1. Because of the number of different surveillance methodologies used in the CDV literature, I was also interested in exploring how surveillance method can impact the types of data that are obtained and the potential impacts for data integration and interpretation. I found that 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. Using regression analyses, I also identified statistically significant associations between the presence of CDV and host and environmental variables that were at times, discordant between the two datasets. Based on some of the challenges and limitations identified, I undertook a scoping review to explore the broader Canadian wildlife surveillance context to identify patterns and inform areas for growth and improvement. The results of the scoping review provide a synopsis of 10-years of published Canadian wildlife health surveillance and identify five primary areas of focus moving forward. Overall, this thesis contributes important knowledge towards a regional understanding of the ecology of CDV in wildlife while at the same time, highlighting the importance of understanding the limitations of our data. The concepts discussed, including challenges, limitations, and opportunities, are broadly applicable across wildlife health surveillance (and research) programs.
Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.
Comment cette classification a été obtenuedéplier
Prédiction machine sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Le volet Gemma est une étiquette directe du modèle pour chaque travail de la base, lue sur la notice réduite au titre. Le volet Codex est un classifieur appris des 10 348 étiquettes directes de Codex et calibré sur les taux pondérés de l'échantillon; les champs sans appui suffisant ne portent aucun appel Codex. Le mode candidate est l'union des deux volets; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont pas des étiquettes humaines.
Scores du classifieur distillé par catégorie (deux têtes)
| Catégorie | Codex | Gemma |
|---|---|---|
| Métarecherche | 0,003 | 0,005 |
| Méta-épidémiologie (sens strict) | 0,000 | 0,000 |
| Méta-épidémiologie (sens large) | 0,000 | 0,000 |
| Bibliométrie | 0,001 | 0,002 |
| Études des sciences et des technologies | 0,002 | 0,002 |
| Communication savante | 0,004 | 0,002 |
| Science ouverte | 0,001 | 0,002 |
| Intégrité de la recherche | 0,001 | 0,001 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,001 | 0,000 |
Scores machine (provisoires)
Les deux têtes enseignantes du modèle étudiant, lues sur ce travail. Un score ordonne la base pour la relecture; il n'affirme jamais une catégorie, et le statut de validation accompagne chaque rangée tel quel.
Scores de référence d'un modèle non mature (critères de maturité non atteints, 7 itérations). Un score ordonne; il n'affirme jamais une catégorie.
score_only:v0-immature-baseline · tel quel depuis la passe de notation : score_only signifie que le nombre peut ordonner les travaux, et qu'aucune étiquette de catégorie n'en découleClassification
machine, non validéePrédiction automatique; un appel candidat d’une seule source (Gemma direct ou Codex distillé), pas un consensus.
Le détail, modèle par modèle et score par score, se trouve en fin de page sous « Comment cette classification a été obtenue ».