One health strategies for zoonosis prevention in developing countries: A systematic review (2015-2025)

Despite growing global investment in One Health initiatives, limited systematic synthesis exists examining veterinary authority strategies and their performance outcomes in developing countries, creating a knowledge gap for evidence-based policy formulation.

To develop a comprehensive taxonomy of One Health zoonosis prevention strategies implemented by veterinary authorities in developing countries and establish quantitative effectiveness patterns across resource-constrained settings.

We conducted a systematic review following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 guidelines, searching Scopus, Web of Science, and PubMed for peer-reviewed studies published between January 2015 and July 2025. Two reviewers independently screened 126 records after deduplication with inter-rater agreement (κ = 0.82). We employed mixed-methods synthesis integrating thematic analysis and quantitative effectiveness scoring across 42 included studies.

From 42 studies spanning 18 countries, we identified 14 distinct One Health strategies organized into three dominant modalities: intersectoral coordination mechanisms (35.7%), surveillance system enhancement (28.6%), and integrated service delivery (21.4%). Integrated approaches consistently demonstrated superior effectiveness scores (77-90, 95% CI: 73-94) compared to single-intervention strategies (25-95, 95% CI: 18-88). Mobile surveillance systems achieved 14-fold reporting increases (RR = 14.0, 95% CI: 13.8-14.2), while integrated surveillance systems demonstrated improved epidemiological understanding across human-animal interfaces.

Implementation quality and strategic integration represent more critical determinants of success than intervention type or resource intensity alone. Sub-optimal policy implementation and poor inter-sectoral coordination were consistently identified as barriers to achieving desired outcomes. These findings provide evidence-based guidance for optimizing limited resources in developing countries.