Comparative Seroprevalence of Antibodies in Canine and Feline Populations

Thesis Abstract

Understanding seroprevalence patterns of infectious diseases in companion animals is essential for informing vaccination strategies, disease surveillance, and public health risk assessment. This study addresses the comparative seroprevalence of antibodies against common canine and feline pathogens—specifically Canine Parvovirus (CPV), Canine Distemper Virus (CDV), Feline Panleukopenia Virus (FPV), and Feline Herpesvirus (FHV-1)—in urban and peri-urban populations within a defined metropolitan region, where disparate vaccination uptake and owner practices may influence exposure risk. The aim is to quantify interspecies differences in seroprevalence, identify associated risk factors, and evaluate the concordance between reported vaccination status and serological evidence. Specific objectives are to (i) determine the seroprevalence of CPV, CDV, FPV, and FHV-1 antibodies in dogs and cats; (ii) compare seroprevalence by species, breed, age, sex, and vaccination status; (iii) assess the influence of habitat (household, shelter, or clinic populations) and owner-reported preventive practices on serostatus; (iv) examine associations between seroprevalence and documented vaccination histories using logistic regression; and (v) propose evidence-based recommendations for vaccination and surveillance programs. A cross-sectional design with a stratified sampling approach will be employed. Blood samples (n = 1,200; 600 canine and 600 feline) will be collected from veterinary clinics, animal shelters, and households over 12 months to account for seasonal variation in exposure. Serological analysis will utilize commercially validated enzyme-linked immunosorbent assays (ELISAs) for CPV, CDV, FPV, and FHV-1 antibodies, with neutralization tests conducted for a subset (n = 200 per species) to confirm equivocal results. Data on demographics, vaccination history, prior infection, living conditions, and preventive practices will be captured via structured owner questionnaires and veterinary records. Data analysis will proceed in three stages (i) descriptive statistics to estimate seroprevalence and 95% confidence intervals by species, age group, and habitat; (ii) bivariate analyses using chi-square tests and t-tests to identify potential associations; and (iii) multivariable logistic regression models to determine independent predictors of seropositivity for each pathogen, including interaction terms between species and vaccination status. Model fit will be evaluated with Hosmer-Lemeshow tests and area under the ROC curve. A secondary analysis will apply a Bayesian hierarchical framework to account for clustering by collection site and to estimate posterior probabilities of seropositivity given vaccination and exposure variables. Theoretical grounding will draw on the Health Belief Model to interpret owner preventive behaviors and the One Health framework to contextualize cross-species seroprevalence within shared environmental exposures. Expected findings include higher seroprevalence for vaccine-targeted antibodies in vaccinated individuals, residual seropositivity in unvaccinated animals suggesting natural exposure or maternal antibodies, and notable interspecies differences in exposure risk linked to owner practices and living conditions. The study anticipates potential under-vaccination in specific subgroups, with shelter populations exhibiting higher exposure to CPV and FPV compared with household pets. The contribution to knowledge lies in providing robust comparative seroprevalence estimates, identifying actionable risk factors for targeted vaccination and surveillance, and highlighting gaps between vaccination records and serological protection. The study will inform policy recommendations for veterinarian-led vaccination campaigns, guidance for shelter infection control, and community education to improve preventive care. Conclusion and recommendations will emphasize strengthening vaccination uptake, aligning serological surveillance with vaccination records, and enhancing owner awareness of durability of immunity and the potential need for booster doses. Limitations include potential seroreversion over time, cross-reactivity in serological assays, and reliance on owner-reported data. Further research suggestions include longitudinal cohort studies to track seroconversion dynamics, evaluation of maternally derived antibody decay in kittens and puppies, and cost-effectiveness analyses of integrated vaccination-surveillance programs.