Biomphalaria species distribution and its effect on human Schistosoma mansoni infection in an irrigated area used for rice cultivation in northeast Brazil
AbstractThe role of irrigated areas for the spread of schistosomiasis is of worldwide concern. The aim of the present study was to investigate the spatial distribution of the intermediate snail host Biomphalaria in an area highly endemic for schistosomiasis due to Schistosoma mansoni, evaluating the relationship between irrigation and types of natural water sources on one hand, and the influence of place and time of water exposure on the intensity of human infection on the other. A geographical information system (GIS) was used to map the distribution of the intermediate snail hosts in Ilha das Flores, Sergipe, Brazil, combined with a clinical/epidemiological survey. We observed a direct correlation between the intensity of human infection with S. mansoni and irrigation projects. Malacological studies to identify snail species and infection rates showed that B. glabrata is the main species responsible for human schistosomiasis in the municipality, but that B. straminea also plays a role. Our results provide evidence for a competitive selection between the two snail species in rice fields with a predominance of B. glabrata in irrigation systems and B. straminea in natural water sources.
- Abstract views: 1275
- PDF: 596
Copyright (c) 2012 Delmany Moitinho Barboza, Cangjie Zhang, Nathaly Cardoso Santos, Marília Matos Bezerra Lemos Silva, Carla Virgínia Vieira Rollemberg, Fabio Jorge Ramalho de Amorim, Marlene Tiduko Ueta, Claudia Moura de Melo, José Antônio Pacheco de Almeida, Verónica de Lourdes Sierpe Jeraldo, Amélia Ribeiro de Jesus
This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.