Anopheles diversity and malaria infection in the cocais zone, state of Maranhão, Brazil

A survey of the Anopheles species was conducted in the municipality of São Mateus, in the state of Maranhão. Species hematophagy habits, the influence of seasonality as well as the vector's infection by Plasmodium were studied. The female Anopheles mosquitoes were captured between February and December 2010 and in March 2012, from 18h00 to 21h00, in intra and peridomiciles. PCR was used for the infection studies. A total 615 specimens of Anopheles were captured, of which 223 (36.2%) in the locality of Piquizeiro and 392 (63.8%) on the Retiro Velho Farm belonging to the species An. nuneztovari, An. darlingi, An. triannulatus, An. albitarsise, and An. oswaldoi. In Piquizeiro most specimens were captured in the intradomiciliary area, while on the Retiro Velho Farm they were mostly found in the peridomiciliary area. The results show the influence of seasonality and time of capture in the hematophagy frequency of the captured Anopheles. The negative result for Plasmodium infection demonstrates a reduction in the number of malaria cases in the State during the study period

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.

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. .

The fauna of phlebotomines (Diptera, Psychodidae) in different phytogeographic regions of the state of Maranhão, Brazil / Fauna de flebotomíneos (Diptera, Psychodidae) em municípios de diferentes fitorregiões, no estado do Maranhão, Brasil

Phlebotomine specimens were captured in domiciliary and forest environments in 47 municipalities between 1982 and 2005 with the aid of CDC light traps. A total of 91 species were found, of which four belonged to genus Brumptomyia and 87 to genus Lutzomyia, distributed among the following subgenera: Evandromyia (6), Lutzomyia (5), Micropygomyia (2), Nyssomyia (9), Pintomyia (2), Pressatia (3), Psathyromyia (6), Psychodopygus (14), Sciopemyia (4), Trichophoromyia (2), Viannamyia (2); species groups: Aragaoi (2), Baityi (1), Dreisbachi (1), Migonei (12), Oswaldoi (8), Pilosa (1), Saulensis (2), Verrucarum (4) and ungrouped (1). Species diversity was greatest in areas where there was dense evergreen seasonal forest (52 species), ombrophilous forest (31) and meridional cerrados (23) and lowest in areas with mixed forest (forest with babassu palms, cerrado and caatinga). The greatest similarity index was observed for restinga and open evergreen seasonal forest (J=0.48). Dense evergreen seasonal forest had greatest similarity with ombrophilous forest (J=0.38). The phlebotomine fauna was species rich and unevenly distributed in Maranhão, reflecting the phytogeographical complexity of the state, which is a result of the great variety of ecosystems and climate zones.

Espécimes de flebotomíneos foram capturados nos anos de 1982 a 2005, em ambientes domiciliares e florestais de 47 municípios, com uso de armadilhas luminosas CDC. Foram encontradas 91 espécies, sendo quatro pertencentes ao gênero Brumptomyia e 87 ao gênero Lutzomyia, distribuídas nos seguintes subgêneros: Evandromyia (6), Lutzomyia (5), Micropygomyia (2), Nyssomyia (9), Pintomyia (2), Pressatia (3), Psathyromyia (6), Psychodopygus (14), Sciopemyia (4), Trychophoromyia (2), Viannamyia (2); grupo de espécies: Aragaoi (2), Baityi (1), Dreisbachi (1), Migonei (12), Oswaldoi (8), Pilosa (1), Saulensis (2), Verrucarum (4) e não agrupada (1). A diversidade de espécies foi maior nas áreas de floresta estacional perenifólia densa (52 espécies), floresta ombrófila (31) e cerrados meridionais (23), sendo menor nas áreas de matas mistas (floresta com babaçu, cerrado e caatinga). O maior índice de similaridade foi observado entre a restinga e a floresta estacional perenifólia aberta (J = 0,48). A floresta estacional perenifólia densa apresentou maior similaridade com a floresta ombrófila (J = 0,38). A fauna de flebotomíneos mostrou-se rica e distribuída de maneira heterogênea no Maranhão, concordando com a complexidade fitogeográfica do Estado, que se manifesta na riqueza de ecossistemas e de zonas climáticas.

Distribution of Lutzomyia whitmani in phytoregions of the state of Maranhão, Northeastern Brazil.

The study had the aim of characterizing the geographical distribution of Lutzomyia whitmani s.l. in the state of Maranhão, Northeastern Brazil. Between 1992 and 2005, 9,600 specimens (65.1% males and 34.9% females) were caught in the rural and urban zones of 35 municipalities in regions consisting of forests, savanna and mixed vegetation with coconut plantations, sandbanks and heath. Greater abundance was observed in areas surrounding dwellings (91.6%) than inside the dwellings (8.4%). The presence of the vector in different phytoregions and in rural and urban areas favors the transmission of tegumentary leishmaniasis in these environments. This taxon may constitute a complex of species in Maranhão, which can be confirmed by molecular biology studies.

Distribuição de Lutzomyia whitmani em fitorregiões do estado do Maranhão, Brasil / Distribution of Lutzomyia whitmani in phytoregions of the state of Maranhão, Northeastern Brazil

O estudo teve por objetivo caracterizar a distribuição geográfica de Lutzomyia whitmani s.l. no estado do Maranhão. De 1992 a 2005, foram capturados 9.600 espécimes (machos: 65,1 por cento e fêmeas: 34,9 por cento) nas zonas rurais e urbanas de 35 municípios situados em áreas de floresta, cerrado e vegetação mista com cocal, restinga e caatinga. A abundância foi maior no peridomicílio (91,6 por cento) do que no intradomicílio (8,4 por cento). A ocorrência do vetor em diferentes fitorregiões e nas áreas rurais e urbanas favorece a transmissão da leishmaniose tegumentar nesses ambientes. É possível que esse táxon constitua um complexo de espécies no Maranhão, o que poderá ser confirmado mediante estudos de biologia molecular.

The study had the aim of characterizing the geographical distribution of Lutzomyia whitmani s.l. in the state of Maranhão, Northeastern Brazil. Between 1992 and 2005, 9,600 specimens (65.1 percent males and 34.9 percent females) were caught in the rural and urban zones of 35 municipalities in regions consisting of forests, savanna and mixed vegetation with coconut plantations, sandbanks and heath. Greater abundance was observed in areas surrounding dwellings (91.6 percent) than inside the dwellings (8.4 percent). The presence of the vector in different phytoregions and in rural and urban areas favors the transmission of tegumentary leishmaniasis in these environments. This taxon may constitute a complex of species in Maranhão, which can be confirmed by molecular biology studies.

[Lutzomyia whitmani periurbanization in a focus of cutaneous leishmaniasis in the State of Maranhão, Brazil]. / A periurbanização de Lutzomyia whitmani em área de foco de leishmaniose cutânea, no Estado do Maranhão, Brasil.

An entomological survey was performed in the periurban area of the municipality of Dom Pedro in the state of Maranhão in 2000, in order to estimate the abundance of Lutzomyia longipalpis, due to the occurrence of one suspect death caused by kala azar. However, it was surprisingly verified that 82.4% (2,440 specimens) from the total of 2,961 sand flies captured in the peridomicile were Lutzomyia whitmani. This association has indicated a new pattern for cutaneous leishmaniasis transmission (urban), as has been observed with regard to kala azar in the northeast of Brazil.

A periurbanização de Lutzomyia whitmani em área de foco de leishmaniose cutânea, no Estado do Maranhão, Brasil / Lutzomyia whitmani periurbanization in a focus of cutaneous leishmaniasis in the State of Maranhão, Brazil

Em um inquérito entomológico realizado em 2000, na zona periurbana do município de Dom Pedro-MA, pretendia-se estimar a abundância de Lutzomyia longipalpis, por conta da ocorrência de um óbito suspeito de calazar. Entretanto, constatou-se que do total de 2.961 flebótomos capturados no peridomicílio, 82,4 por cento (2.440 espécimes) eram de Lutzomyia whitmani. Esta associação vem determinando um novo padrão de transmissão da leishmaniose cutânea (o urbano), como vem acontecendo com o calazar nordestino.

Flebotomíneos (Diptera, Psychodidae) de área endêmica de leishmaniose na região dos cerrados, Estado do Maranhão, Brasil / Sandflies (Diptera, Psychodidae) from an endemic leishmaniasis area in the cerrado region of the State of Maranhão, Brazil

Apresentam-se dez espécies do gênero Lutzomyia França, 1924, encontradas nos cerrados do nordeste maranhense. As capturas foram realizadas das 18h às 6h, uma vez por mês, durante nove meses, nos municípios de Aldeias Altas, Capinzal do Norte, Caxias, Codó, Coelho Neto, Timbiras, Timon e Tuntum, áreas endêmicas das leishmanioses visceral e tegumentar. No total, foram capturados 1.868 espécimens em armadilhas luminosas tipo CDC, sendo 377 no intradomicílio (64,7 por cento machos e 35,3 por cento fêmeas) e 1.491 no peridomicílio (73 por cento machos e 27 percent fêmeas). As espécies encontradas foram as que seguem: Lutzomyia cortelezii, Lutzomyia evandroi, Lutzomyia goiana, Lutzomyia intermedia, Lutzomyia lenti, Lutzomyia longipalpis, Lutzomyia longipennis, Lutzomyia squamiventris, Lutzomyia termitophila e Lutzomyia whitmani. As mais abundantes no intra e no peridomicílios foram L. longipalpis (67,4 por cento e 70,2 por cento, respectivamente) e L. whitmani (31 por cento e 24,7 por cento, respectivamente). L. longipalpis ocorreu em todos os meses estudados, nas estações seca e chuvosa, e em todas as localidades trabalhadas