Poster 214 - Epidemiology of snakebites in Brazil 18 years after the implementation of the National

Poster 214. Congresso da Sociedade Brasileira de Toxinologia, 8., Symposium of the Pan American Section of the International Society on Toxinology, 8., 2004, Angra dos Reis, Brasil. Abstracts... J. Venom. Anim. Toxins incl.Trop. Dis., 2004, 10, 3, p.573.

Epidemiology of snakebites in Brazil18 years after the implementation of the National Program for Snakebites Control.

Snakebites continue to be public heath problem in Brazil, responsible for high indexes of morbidity and lethality. The National Program for Snakebites Control was implemented by the Ministry of Health to reach auto-sufficiency in antivenom production and to provide epidemiological information, by a national health information system. Data obtained from this system indicated that 21,716 snakebites occurred in 2002 (incidence of 12 cases per 100,000 population); 319,342 ampoules were acquired and distributed free of charge for the whole country. The risk of accidents was much higher in the Amazon region, which had the highest incidence coefficient (42/100,000). Bothrops snakebites were reported to occur in 84.0%, while Crotalus, Lachesis and Micrurus were responsible for 9.8, 2.6 and 0.6% of cases; non-poisonous snakes were identified to cause only 2.9% of all cases. Of the total, antivenom therapy was reported in 82.1%, ranging from 86,1% for Bothrops accidents to 65.6% for Micrurus accidents. The number of ampoules per case varied according to the type of envenoming: 6.7 for Bothrops, 10.4 for Crotalus, 7.1 for Lachesis and 7.6 for Micrurus cases. Case-fatality rate maintained low during the years: in 2002 113 deaths were registered (0.5%). Patients who arrived at the hospital more than 12 hours after bite had almost 4 times more risk of death when compared to those who arrived in the first 3 hours. Lethality of Crotalus envenoming was higher (1.3%) than Bothrops (0.4%) and Lachesis (0.8%); no deaths caused by Micrurus was detected in 2002. Free of charge distribution of antivenom for the whole country certainly contributed to decline mortality but these figures have not been changing for years. Also, number of cases had not decline along the last two decades, revealing that educational programmes failured to reduce incidence of snakebites. Special focus should be given to the Amazon region where time between accident and treatment and type of envenoming revealed to be important associated factors for lethality.