Longitudinal clinical and serological survey of abdominal angiostrongyliasis in Guaporé, southern Brazil, from 1995 to 1999

Angiostrongilíase abdominal é uma zoonose causada pelo Angiostrongylus costaricensis, nematódeo que se localiza no interior de vasos mesentéricos. Nosso objetivo foi de abordar vários aspectos da história natural da parasitose, num estudo longitudinal clínico-sorológico. Um total de 179 indivíduos residentes em área rural no sul do Brasil, com transmissão ativa, foram seguidos por cinco anos. Neste período foram registradas prevalências de 28,2%, 4,2%, 10%, 20,2% e 2,8% e incidências de 0%, 5,9%, 8% e 1,5%. Tanto o sexo masculino quanto o feminino foram afetados com maiores frequências na faixa etária dos 30 aos 49 anos. Em 32 indivíduos, amostras de soro foram coletadas em todas as etapas e a reatividade de IgG detectada por ELISA foi variável e geralmente não persistindo mais do que um ano. Alguns padrões individuais foram sugestivos de re-infecção. Não houve associação com a ocorrência nem de dor abdominal nem com outras enteroparasitoses e não houve nenhum caso com diagnóstico confirmado (histopatológico) da infecção. Moluscos foram encontrados portando larvas infectantes de terceiro estadio, em algumas moradias, com uma prevalência geral de 16% e baixas cargas parasitárias. Em conclusão, a angiostrongilíase abdominal no sul do Brasil pode ser uma infecção frequente, porém com baixa morbidade e reatividade sorológica de gradual declínio.

The initial epidemiological studies in the low endemicity schistosomiasis area in esteio, Rio Grande do Sul, the southernmost Brazilian State, 1997 to 2000

Nor Biomphalaria glabrata neither Schistosoma mansoni were reported from Rio Grande do Sul, the southernmost Brazilian state before 1997. Their detection next to the Sinos River, Esteio, confirmed predictions of schistosomiasis expansion to the south. Parasitological examinations both in snails and fecal samples from the human population were performed from 1997 to 2000. The last 3 out of 5 surveys were performed after a preliminar serological screening procedure in a risk group identified at a population census. A total of 11 infected individuals were found infected and snails from 2 different sites were positive for S. mansoni. Samples from these 2 and other sites were identified as B. glabrata. Egg counts in feces were below 1 per gram in 6 out of 11 patients. Some socio-cultural perceptions of water contact activities next to the Sinos River may cause difficulties to control efforts, but they also may be partially acting against a very rapid increase in transmission intensity. The southernmost schistomiasis mansoni foci in Americas rise the alert for its ongoing expansion.

The initial epidemiological studies in the low endemicity schistosomiasis area in esteio, Rio Grande do Sul, the southernmost Brazilian State, 1997 to 2000

Nor Biomphalaria glabrata neither Schistosoma mansoni were reported from Rio Grande do Sul, the southernmost Brazilian state before 1997. Their detection next to the Sinos River, Esteio, confirmed predictions of schistosomiasis expansion to the south. Parasitological examinations both in snails and fecal samples from the human population were performed from 1997 to 2000. The last 3 out of 5 surveys were performed after a preliminar serological screening procedure in a risk group identified at a population census. A total of 11 infected individuals were found infected and snails from 2 different sites were positive for S. mansoni. Samples from these 2 and other sites were identified as B. glabrata. Egg counts in feces were below 1 per gram in 6 out of 11 patients. Some socio-cultural perceptions of water contact activities next to the Sinos River may cause difficulties to control efforts, but they also may be partially acting against a very rapid increase in transmission intensity. The southernmost schistomiasis mansoni foci in Americas rise the alert for its ongoing expansion.