Distribution of snake species and snakebites in hotspots of Ethiopia

Abstract

Introduction: In Sub-Saharan Africa, snakebites are a public health problem. In Ethiopia, clinical cases have been described, but little information exists on snakebites burden and its geographical distribution. The aim of this study was to document the spatial distribution of venomous snakes and snakebites in Ethiopia.

Methodology: In a cross-sectional observational study, venomous snakes were collected during snake catching activities in six Ethiopian hotspot areas between April 2015 and September 2020. Species and habitat were described. In the hotspot areas, routine health information data on reported snakebites was collected in 78 districts and subsequently used to map annual incidence per district.

Result: A total of 333 snakes were collected and 14 species were identified. The most prevalent species were Bitis arietans, Bitis arietanus somalica, Echis pyramidum, known as vipers, and Naja pallida, known as cobra. The highest number of snakes (75) was observed in the Northwest and Eastern parts of Ethiopia, mostly in cultivation and man-made farm land, wooded and moist dry savanna. In each hotspot a wide variety of species was observed, although composition was different. The highest snakebite incidence overlapped with the high snakes densities in Northwest Ethiopia. The snakebite annual average incidence at district level was very heterogeneous and ranged from < 15 cases/100,000 inhabitants (44% of the districts) to 309.2 cases/100,000 inhabitants.

Conclusions: Snake diversity and distribution, linked to high incidence of snakebites in the hotspots, suggests a close interconnection between human, animal and environmental systems and could inform the need for antivenoms per geographical locality.