Parvovirus enteritis in Nigerian dogs: A Systematic Review (2009–2025) and a Six-Year Retrospective Cohort in the Veterinary Teaching Hospital, University of Ibadan

Canine parvovirus (CPV) enteritis is a leading cause of canine morbidity and mortality in Nigeria. This study synthesized evidence via a systematic review of the Nigerian literature (2009-2025) and a six-year retrospective cohort analysis of 415 laboratory-confirmed cases from the University of Ibadan Veterinary Teaching Hospital (2018-2024) to identify risk factors and quantify vaccine impact. A systematic search of Scopus, Web of science, PubMed, and AJOL identified peer-reviewed articles for qualitative synthesis. Retrospective data from the Veterinary Teaching Hospital, University of Ibadan, were analyzed for demographic patterns, and Chi-square tests assessed vaccination impact on survival across breeds and clinical severity strata. Meta-analysis identified young age (<24 weeks), incomplete vaccination, breed predisposition (notably Boerboels and German Shepherds), and environmental exposure as principal risk factors. The retrospective cohort showed a near-balanced sex ratio (52.1% female) and a mean age of 21.44 ± 22.77 weeks. Vaccination significantly improved survival (Table 2): 76.6% (49/64) of vaccinated dogs survived versus 49.6% (68/137) of unvaccinated dogs (χ² = 33.95, p < 0.001). This benefit was consistent across breeds, most markedly in Boerboels (93.3% vs. 46.2%; p = 0.002) (Figure 5), and persisted when stratified by clinical severity, including in dogs presenting with >two clinical signs (76.0% vs. 44.1%; χ² = 16.39, p = 0.003). This literature review suggests vaccine failures were linked to logistical issues like suboptimal handling and maternally derived antibody interference. We conclude that prior vaccination is strongly associated with a profound survival advantage in Nigerian dogs with CPV enteritis. Strengthening early diagnosis, optimizing vaccine delivery protocols, and ensuring complete vaccination schedules are critical to reducing the endemic CPV burden.