Factors affecting snakebite mortality in north-eastern Nigeria.

Snakebite is an important cause of mortality among rural dwellers in the savannah region of West Africa. We conducted a retrospective review of snakebite patients managed by experienced medical staff at Kaltungo in north-eastern Nigeria to determine the cause of death. During a 36 month period there were 94 deaths among 6687 victims (1.41%). Relative risk (RR) of mortality increased to 2.29 (95% CI 1.35-3.89) during a period when source of antivenom became unreliable. The increase was not due to seasonal variation. In a logistic regression model predictors of mortality were new central nervous system (CNS) features (Odds ratio (OR) = 24.61; 95% CI 6.93-87.41) and delay from bite to hospitalization (OR for every 1 h delay = 1.01; 95% CI 1.00-1.02). Treatment with antivenom was protective (OR = 0.17; 95% CI 0.03-0.96). Relationship of anaemia and shock to mortality were not maintained following adjustment. Effort should be made to provide regionally appropriate, affordable and effective antivenoms in addition to enforcement of continuous regulatory control measures. Antivenoms should be distributed to affected areas and treatment access points of care expanded to communities to diminish travel time. The populations at risk should be educated on avoiding unnecessary delays and on prevention of bites.