CaracterizaÃÃo do ambiente fÃsico-quÃmico e biolÃgico de Biomphalaria glabrata em focos litorÃneos de esquistossomose em Pernambuco

AUTOR(ES)
DATA DE PUBLICAÇÃO

2004

RESUMO

In Pernambuco schistosomiasis mansoni is historically endemic in the country side. However, concentration of this disease is occurring in areas of the littoral in the state of Pernambuco and they were detected serious infections in localities like Itamaracà Island, Porto de Galinhas and JaboatÃo dos Guararapes. This situation was detected since the exodus of the rural workers, many times infected by the S. mansoni, who lives in the uptown area of these localities with poor health conditions, and contaminate water bodies which are inhabitted by the gastropod Biomphalaria glabatra. To explain the presence of this gastropd in these water bodies considered before as âfreeâ from these animals and also to better understand the aspect of the expansion of the schistosomiasis mansoni in our State, we investigated physical, chemical and biological parameters related to the survival of the transmitter animal, as salinity, iron, calcium and phytoplakton, among other analysis, in the waters and in the sediments of the investigated localities through samplings of these material, carried out during the dry and rainny periods, from September/2002 to December/2003. Among the several analysed environments, the predomiciliar areas of the âOlho DâÃguaâ lagoon in JaboatÃo dos Guararapes was the most salinated. The average of 7.7%0 is about 15 times above the maximum value established by the agency CONAMA 20/86 which is 0.5%o to freshwaters. The mean concentration of sulphate (489 mg.L-1) represented almost twice of the established by the referred resolution which is 250 mg.L-1. These high values may be explained by the influence of the tides in the waters which communicate with this lagoon. Iron is in the maximum established level by the law, which is 0.3 mg.L-1. The rest of the analysed sites present physical and chemical characteristics of freshwater mainly the âConstanÃaâ Lagoon in Itamaracà Island which represented the most propicious environment to the development and survival of the snails host. Accordingly to the results, the waters from the âOlho dâÃguaâ Lagoon are brakish which represents some way a change of the environment of the species Biomphalaria glabatra considered typical of freshwater. The environmental changes and the characteristics of littoral areas, present salinity above the levels tolerated by the snail host which leads to the selection of more resistent species to some natural present chemical compounds in the studied localities or introduced by men when we pollute the water bodies

ASSUNTO(S)

biomphalaria glabrata ecologia salinidade engenharia civil

ACESSO AO ARTIGO

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