Epidemiology of snakebite in Eshowe, KwaZulu-Natal, South Africa

Three hundred and thirty-three patients admitted to Eshowe Hospital with snakebite were analysed. Forty-one were non-envenomed, 282 exhibited painful progressive swelling (PPS), seven showed progressive weakness (PW), and there were three cases of minor envenomations that were unclassifiable. Offending dead venomous snakes included Naja mossambica (Mozambique spitting cobra), Bitis arietans (puff adder), Atractaspis bibronii (stiletto snake), Causus rhombeatus (common night adder) and Dendroaspis polylepis (black mamba). Most bites occurred on the leg in the wet summer months during the first three decades of the patients' lives. The majority of patients used a first-aid measure. The snake was most commonly sighted if the patient was bitten on an upper limb or above the ankle. Severe envenomation was associated with quicker arrival at hospital, and multiple bites occurred more frequently in sleeping patients. Non-envenomation following snakebites was more common in winter, in adult females, and if the patient was bitten proximally on a limb or on a hand. Patients with PPS developed bite site complications (42), compartment syndromes (4), femoral vessel entrapment (1), deep vein thrombosis (1), and respiratory complications (4). Severe swelling was associated with spring and early summer, proximal limb bites and children who were most at risk of necrosis. Fingers and hands were most prone to necrosis and permanent disability. Four patients with PW developed respiratory failure. Antivenom was administered to 12 patients, five of whom developed an acute adverse reaction. There was one death.