ECOLOGIA DE FLEBOTOMÍNEOS EM ÁREAS RURAIS ANTIGAS E RECENTES, COM DIFERENTES GRAUS DE DESMATAMENTOS FLORESTAIS, EM BIOMA DE CERRADO DO ESTADO DO MARANHÃO

Abstract

American tegumentary leishmaniasis (ATL), a tegument and/or mucous membranes inflammatory disease, is an endemic disease in Maranhão state, especially in villages within the cerrado biome region. Extensive areas of cerrado located in the municipalities of Chapadinha and Barreirinhas suffer degradation caused by human occupation processes such as urbanization, agricultural activity, livestock and coal production that enable the occurrence of ATL by elimination or reduction of natural habitats for both reservoirs and the vectors. The research investigated ecological aspects of phlebotomic fauna in anthropogenic and wild environments in the cerrado biome. Sandflies samples were captured in forest fragments and peridomestic environments of two forest areas into the cerrado biome in the municipalities of Barreirinhas (old area) and Chapadinha (recent area). Specimen collection was carried between 2012 and 2014. In total, 21.708 specimens and 33 species of Lutzomyia and 02 Brumptomyia were collected. The richness and abundance of species were higher in more preserved area (31 species; 61.7%) than degraded area (17 species; 38.3%). Males predominated over females both in the old area (males: 60.35%; females: 39.65%) and recent area (males: 56.95%; females: 43.05%). In the old area, the dominant species were L. longipalpis (47.52%), L. whitmani (27.34%) and L. evandroi (5.03%), L. trinidadensis (3.17%) and L. lenti (3.15%). In the recent area, the two dominant species were the same (L. longipalpis: 38.03%; L. whitmani: 23.89%), but there was a change in the dominance order of the following species: L. lenti (22.94%), L. acanthopharinx (4.23%), L. termitophila (3.52%), L. goiana (2.21%) and L. evandroi (2.2%). In the recent area, more preserved area, the richness of sandflies species was higher in the forest (30 species) than in the intradomiciles (12) and peridomiciles (21). While, in the old area, where the vegetation is more degraded, the richness of sandflies species was higher in the peridomiciles (17) than in the forest (16) and intradomiciles (12). On the whole, the abundance of sandflies species was higher in the rainy season in both localities, reducing in the transition to dry season, increasing again at the end of this last season, evidencing clear seasonality. These results indicate that the abundance was significantly higher in the peridomiciles and many species can be found in all months of the year, but the richness and abundance are higher in the rainy season, when the rainfall and humidity rates are higher and the temperature is milder. This study showed that deforestation that causes forest degradation affects the community structure of sandflies, as the species richness increases in the conserved forest and decreases in the degraded forest; while the abundance decreases in the degraded forest and increases in the peridomiciliar environments of the settlements. This result requires urgency in the development of public policies for forest conservation and entomological monitoring and surveillance in the areas studied.