Snake bites in Zimbabwe: a clinical study with emphasis on the need for antivenom.

A retrospective analysis of 83 consecutive patients (42 males and 41 females) treated for snake bites at Mpilo Central Hospital between January 1990 and June 1992 is presented. In Zimbabwe poisonous snakes belong to four families; Colubrids (Boomslang), Vipers (Puff Adder), Elapids (Mambas and Cobras) and Atractaspids (Bibron Stilleto snake). The Puff Adder is responsible for three quarters of the bites. Forty eight pc (40/83) of the patients were below 20 years of age (range 1 year 10 months to 72 years). Most bites occurred at night (61 pc) in the rainy season (November to April). The majority of snake bites occurred on the lower limb, 64 pc (53/83), with most of the remainder occurring on the upper limb, 34 pc (28/83). The most common clinical features were; pain (95 pc), swelling (87 pc), tachycardia (20 pc), fever (13 pc) and vomiting (8 pc). This study, carried out at a time when there was no antivenom in stock at Mpilo Hospital, shows a considerable mortality (5 pc, 4/83) and morbidity (37 pc, 31/83) rate from poisonous snake bites in Zimbabwe. These observations highlight the need to maintain adequate stocks of antivenom in the major hospitals in Zimbabwe.