The association between animal-keeping practice and human malaria infection: a cross-sectional study in southern Tanzania

Background Malaria remains a leading global health threat, primarily in sub-Saharan Africa. In Tanzania, malaria continues to cause high morbidity and mortality, especially in rural areas. Animal-keeping, common in these regions, may influence the local malaria vector ecology. However, the relationship between animal-keeping and malaria risk remains to be understood, with studies showing mixed results regarding its protective or risk-enhancing effects. This study assessed the associations between malaria infection and animal-keeping practices in rural southern Tanzania, specifically whether animal species (poultry, ruminants, or pets), management location (indoors vs. outdoors), and herd size influence infection risk, providing insights for targeted malaria control strategies within a One Health framework. Methods Data were collected from the baseline survey of the China-Tanzania malaria control project in July 2019, covering three regions: Kibiti, Rufiji and Kilwa. Interviews were conducted with households, including data on living conditions, animal-keeping practices, malaria prevalence, and health-seeking behaviors. Malaria was diagnosed using rapid detection reagents. Univariant analysis and the logistic regression models of exposure-outcome and dosage-outcome were implemented to assess the relationship between malaria infection risk and animal-keeping practices. Results Of the 11,406 participants with malaria RDT results, 6,379 (55.93%) kept animals. Poultry-keeping was consistently associated with increased malaria risk across all analyses (univariant analysis OR 1.51 and 1.66, 95% CI 1.35–1.69, 1.51–1.82; exposure-outcome OR 1.409 and 1.596 with 95% CI 1.256–1.580, 1.450–1.757; dosage-outcome OR 1.018 and 1.014, with 95% CI 1.000–1.037 and 1.009–1.018). Results were robust after considering confounding. Conclusion Poultry-keeping near households is associated with increased malaria risk in rural southern Tanzania. Findings suggest that managing animal placement and housing could enhance traditional vector control. Adopting a One Health framework that integrates veterinary and environmental management is essential for improving malaria intervention outcomes in rural communities.