Snakebite health outcomes and influencing factors in high-incidence Asian countries: A systematic review

Snakebites are a global public health problem and one of the neglected tropical diseases. Community factors and health system factors influence snakebite health outcomes. This systematic review provides evidence of the relationship between snakebite health outcomes and the factors affecting these outcomes among selected Asian countries with high snakebite incidence to guide snakebite management strategies to improve outcomes for snakebite patients. A systematic review was conducted. We searched articles published in English from 2014 to 2024 on PubMed, Scopus and Web of Science, including studies that discussed snakebite patients with envenoming effects who received management at health facilities and mentioned health outcomes and factors influencing those outcomes. Joanna Briggs Institute standard critical appraisal tools were used for quality assessment. A proportional meta-analysis with a random effects model was performed using STATA software to calculate the overall proportion of snakebite health outcomes. The funnel plot and Egger's test were conducted to investigate publication bias. Heterogeneity (I²) and sensitivity analyses were carried out. Initially, 3354 studies were identified. After screening, 18 relevant studies were included in the analysis, which reported a total of 5344 snakebite patients. The overall recovery and death proportions were 94 % (95 % confidence interval [CI]: 0.92, 0.95) and 5 % (95 % CI: 0.03, 0.08), respectively. The heterogeneity (I²) was high, with values of 83.89 % for pooled recovery and 95.70 % for pooled death, owing to the variability in the nature of the included studies. The pooled recovery and death proportions were similar in selected South Asian and Southeast Asian countries. Twenty-six patients required amputations, 30 were discharged or left the hospital against medical advice, and 22 were transferred to other hospitals. Seven studies highlighted community factors (inappropriate first aid methods and delayed arrival at health facilities), three studies mentioned health system factors (antivenom accessibility and availability of competent healthcare providers), and eight studies discussed both factors as influences on snakebite outcomes. This is the first systematic review to highlight the overall influencing factors across the selected multiple countries with high snakebite incidence regions in Asia. It provides cumulative insights into the factors that are reported by individual studies. Further studies may emphasise the context influencing snakebite health outcomes to understand the enduring reasons behind these factors and enhance snakebite management strategies to address these factors.