Epidemiology of schistosomiasis in coastal areas of Pernambuco State, Brazil.

Abstract

The expansion of schistosomiasis to the coast of Pernambuco has been registered since 1992 withthe detection of acute cases of the disease in individuals of middle/upper class. To diagnose thisnew scenario of transmission of schistosomiasis in tourist areas on the waterfront of the state,knowledge of georeferenced species distribution of vector snails through maps that show theirexact location seems essential, as it is necessary to localize situations with biohazard and unhealthyenvironmental conditions. From 15 to 18 September 2008 and 10 to 13 September 2013, expeditionswere conducted by groups of epidemiologists and parasitologists for 11 coastal municipalities ofthe state, checking all the collections of fresh water up to 2 km away from the seaside. Data weregeoreferenced for a later conduction of spatial analysis. For positive identification of Biomphalariaglabrata, the technique of light exposure was used. Specimens of B. straminea that remainednegative until the 15th day underwent the technique of molecular diagnosis (PCR-single tube). Inthe 2008 expedition, 3,392 B. glabrata snails and 725 B. straminea snails were captured, whoseinfection rates ranged from 0.9% to 22.2%. In the 2013 expedition, 948 B. glabrata and 504 B.straminea snails were collected and only in Porto de Galinhas city were B. glabrata snails foundreleasing S. mansoni cercariae, with an infectivity rate of 81.4%, confirming that in this locality therisk of schistosomiasis transmission is still present.