ENVENOMATIONS BY COLUBRID SNAKES IN AFRICA, EUROPE, AND THE MIDDLE EAST

Abstract

Many species of colubrid snakes from Africa, Europe and the Middle East produce toxic oral secretions. However, only a small number has caused envenomation in humans, and very few are of medical concern. Envenomations are rare and almost exclusively result from handling these animals. Apart from the very small group of people who capture and keep venomous colubrids, the health risks from these snakes to the general population are negligible. Envenomations by the majority of venomous colubrids in Africa, Europe and the Middle East will cause local symptoms of pain and edema of variable extent. Systemic envenomation is rare. Severe consumption coagulopathy and hemorrhagic diathesis have followed bites by the African tree snakes Dispholidus typus and Thelothornis capensis, which have a highly developed venom apparatus and extremely toxic venoms, and are capable of inflicting fatal human envenomation with a quick bite. A similar clinical picture was observed in cases of severe envenomation by the Asian colubrid Rhabdophis subminiatus, which has been imported to Europe by the pet trade. The treatment of colubrid envenomations in Africa, Europe and the Middle East is supportive and symptomatic. Careful monitoring of the patient is imperative, and asymptomatic patients should be hospitalized for at least 48 hr when bites were caused by Dispholidus, Thelotornis or Rhabdophis. Intensive care, replacement of blood and infusion of fibrinogen may be required in cases of hemorrhagic diathesis. Antivenoms raised against the venoms of viperid or elapid snakes are ineffective.