EPIDEMIOLOGY OF DEATHS CAUSED BY POISONOUS ANIMALS IN BRAZIL

WEN, F.H.(1)

(1)Hospital Vital Brazil, Instituto Butantan

One of the main objectives of antivenom therapy is preventing the occurrence of deaths. This objective has been partially achieved in the 1980´s by the time the Ministry of Health had implemented the National Program of Snakebites Control, lately named National Program of Control of Accidents Caused by Poisonous Animals. The lethality has been dramatically dropped with the decentralized distribution of antivenom. Nevertheless, about a hundred of deaths have still been registered in whole country, most of them presumably preventable with adequate antivenom therapy and supportive treatment. The causes of mortality are poorly known since the information system of accidents does not emphasize description of complications that may lead to fatal evolution. In parallel, difficulties to perform adequate necropsy also obscure the study of pathophysiological conditions in which patients die. Snakebites are far the most common cause of death among the poisonous animals, followed by scorpion stings. Among the snakes, Crotalus is far the commonest cause of death (lethality = 1.87%), although the absolute number of Bothrops fatal cases is twice higher. Scorpion stings are known to be responsible for systemic severe envenoming in children under 14 years old: the lethality in this age group is about 1.8% while in adults the lethality is less than 0.01%. Spiders seem to be rarely associated with deaths in Brazil. Recently Lonomia caterpillars have been described as an important agent of severe envenomation in southern region of Brazil, and consequently of systemic complications that my lead to fatal outcome in consequence of intracranial hemorrhage and acute renal failure. Before the production of Lonomia antivenom, the calculated lethality was 1.7%, dropping to about 0.3% in patients had received the specific treatment. In conclusion, although lethality by poisonous animals is relatively low, the causes of deaths should be more precisely documented, for a better understanding of the mechanisms of venoms activity and, perhaps most importantly, to be used as a tool for development of public politics of health.

CORRESPONDENCE TO:

WEN, F.H., Hospital Vital Brazil, Instituto Butantan, Avenida Vital Brasil, 1500, São Paulo, 05503-900, SP, Brasil, E.mail: fhui@uol.com.br,  fanhui@butantan.gov.br