Flebotomíneos (díptera, psychodidae) em focos urbanos de leishmaniose visceral no estado do Maranhão, Brasil / Sandflies (Diptera, Psychodidae) in urban outbreaks of visceral leishmaniasis in the state of Maranhão, Brazil

Foram objetos deste estudo a riqueza, a abundância relativa e a frequência mensal das espécies de flebotomíneos (Diptera, Psychodidae) em uma área urbana do município de Codó, estado doMaranhão, que registra elevada prevalência de leishmaniose visceral. Os insetos foram capturados com armadilhas luminosas do tipo CDC, das 18 h às 6 h, duas vezes por mês, de junho de 2012 a maio de 2013. Foram coletados 5.722 espécimes de 11 espécies, sendo 10 pertencentes ao gênero Lutzomyia e 1 ao gênero Brumptomyia. A abundância foi maior no peridomicílio (4.009 exemplares:66 por cento machos e 34 por cento fêmeas) do que no intradomicílio (1.713 exemplares: 55,9 por cento machos e 44,1 por cento fêmeas). A espécie mais abundante foi L. longipalpis (97,7 por cento) e juntamente com L. evandroi, L.sordelli e L. termitophila foram as mais constantes ao longo do ano. A frequência dos flebotomíneos mostrou-se maior no período seco (57,9 por cento), elevando-se com o aumento da temperatura média(p=0,0156; r=0,1007) e reduzindo-se com o aumento da umidade relativa do ar (p=0,0001;r=-0,1740). Sugerem-se ações de controle vetorial durante a estação seca quando os flebotomíneossão mais abundantes.

The richness, relative abundance and the monthly frequency of species of sandflies (Diptera,Psychodidae) in an urban area of the municipality of Codo, Maranhão, a state that records a highprevalence of visceral leishmaniasis, was studied. The insects were captured with CDC light traps,from 18 h to 6 h, twice per month from June 2012 to May 2013 and 5,722 specimens of 11 species, 10belonging to the genus Lutzomyia and one to the genus Brumptomyia were collected. The abundancewas higher outdoors (4,009 samples: 66 percent males and 34 percent females) than in households (1,713 samples:55.9 percent males and 44.1 percent females). The most abundant species was L. longipalpis (97.7 percent), whichtogether with L. evandroi, L.sordellii and L. termitophila were more constant throughout the year. Thefrequency of sandflies was higher in the dry season (57.9 percent), rising with increasing mean temperature(p=0.0156, r=0.1007) and showed a decrease with increasing relative humidity (p=0.0001, r=-0.1740).Vector control during the dry season, when sandflies are most abundant, is suggested.

Spatial dynamics of urban populations of Lutzomyia longipalpis (Diptera: Psychodidae) in Caxias, State of Maranhão, Brazil

Introduction In this paper, we report the ecology of Lutzomyia longipalpis in Caxias City, located in the eastern part of State of Maranhão, Brazil and highlight its seasonal and geographical distribution by environment. In addition, we discuss natural Leishmania infection and its relationship with visceral leishmaniasis. Methods Between September 2007 and August 2009, the collection of sandflies was performed using Center for Disease Control (CDC) light traps from 15 houses in 5 selected neighborhoods. Results Lutzomyia longipalpis was present in all zones of the city. We also found that Lu. longipalpis was regularly detected both inside and around the house, predominantly in outdoor areas. In urban areas, Lu. longipalpis was present in both the dry and rainy seasons, with a higher density present in the latter. One female specimen of Lu. longipalpis was observed to have natural Leishmania infection. Conclusions The presence of Lu. longipalpis was observed throughout the year during 2 seasonal periods, with a predominance in the rainy season. A low rate of natural Leishmania infection was observed in urban areas during the rainy season. .