A systematic review and meta-analysis of incidence and spatiotemporal trends of snakebites in Iran.

Background and Purpose

Snakebites are a neglected public health concern, particularly in tropical regions, causing significant morbidity and mortality. Despite Iran's high snakebite burden, epidemiological data remain inconsistent. This systematic review and meta-analysis aim to provide estimates of snakebite incidence and geographical distribution across Iranian provinces.

Methods

A comprehensive search was conducted in PubMed/MEDLINE, Scopus, Web of Science, Embase, Google Scholar, and Persian databases (Magiran, SID) up to February 2025. Observational studies reporting snakebite incidence in Iran were included. Two independent reviewers screened studies, extracted data, and assessed bias using the Newcastle-Ottawa Scale (NOS). A random-effects meta-analysis was performed, with heterogeneity evaluated via I². Meta-regression analyzed temporal trends.

Results

Of 618 initially identified studies, 8 met the inclusion criteria. This meta-analysis found Iran's overall snakebite incidence to be 31.89 cases per 100,000 population (95% CI: 16.58-47.20), with extreme regional variation (0.14-295.45). Males showed a significantly higher incidence (108.34) than females (66.79). Geographic analysis revealed the highest rates in southeastern (109.68) and southwestern (116.04) regions, and the lowest in northwestern (4.30) and northern (4.05) areas. Meta-regression indicated a significant temporal increase in incidence (β = 0.035, p < 0.001). High heterogeneity (I² ≥ 99.8%) suggests additional underlying factors influence snakebite distribution.

Conclusion

Snakebite incidence in Iran exhibits marked geographical and gender disparities, with an upward temporal trend. These findings highlight the need for targeted prevention strategies, improved antivenom access, and enhanced surveillance in high-risk provinces.