Modelagem de nicho ecológico de Biomphalaria spp (Preston,1910) no Estado do Espírito Santo-Brasil

Abstract

Schistosomiasis mansoni is a parasitic disease caused by Schistosoma mansoni. The transmission occurs by aquatic mollusks, of the genus Biomphalaria, having three species of epidemiological importance (Biomphalaria glabrata, Biomphalaria straminea and Biomphalaria tenagophila). In Brazil, the species Biomphalaria glabrata is the most important intermediate host, due to its extensive geographical distribution, high infection rates and infection transmission efficiency. Schistosomiasis is endemic in 47 of the 78 municipalities of Espirito Santo (ES), where the most important foci are located in the central and southern regions of the state; Baixo Guandu and Vale do Rio Doce. Objective: In this work, was analyzed the predictive distribution of the main species of Biomphalaria and the relationship with the transmission of schistosomiasis mansoni in the ES state. Materials and methods: The historical series from 2000 to 2016 were collected by the Center of Entomology and Malacology of ES State and evaluated by geoclimatic maps. Nineteen variables were analyzed by WorldClim program, temperature, rainfall, altitude and slope that was available by IBGE, and soil by EMBRAPA / IBGE. The ArcGIS and Maxent programs were used to analyze the data and elaborate the prediction maps. Results: Out of 23,738 samples of Biomphalaria planorbids and 39,808 positive cases of schistosomiasis mansoni were evaluated in the ES state. These results were obtained from geoprocessing and modeling, which allowed to conclude that some variables such as temperature and precipitation, are highly related to the presence of these planorbids in the state. Conclusions: This study presents, for the first time, the map of the occurrence of schistosomiasis mansoni in the ES state, proving the association of the distribution depends of the temperature, precipitation and altitude in addition to identifying the areas of higher probability of occurrence of Biomphalaria genus.