Influence of Deforestation on the Community Structure of Sand Flies (Diptera: Psychodidae) in Eastern Amazonia.

Variation in the structure of phlebotomine (sand fly) communities in forest fragments with different degrees of preservation and human occupation (peridomicile) in eastern Amazonia was studied. We identified 43 species of sand flies in our study, of which 38 occurred in both preserved forest areas and in the peridomiciles of short-term settlements, while another 28 species occurred in altered forest fragments and long-term settlements. The composition of the community at each site changed with the type of environment (forest or peridomicile), with the species Lutzomyia evandroi, L. whitmani, L. choti, L. serrana, L. triacantha, L. migonei, L. hirsuta, L. shannoni, and L. brachyphylla accounting for more than 54% of the differences among environments. The quality of the environment exerted a significant influence on the structure of phlebotomine communities, and affected their species composition, richness, and abundance.

Molecular Identification of Leishmania spp. in Sand Flies (Diptera: Psychodidae: Phlebotominae) in the Lençóis Maranhenses National Park, Brazil.

Sand flies are very common in the region of Lençóis Maranhenses National Park, an important tourist attraction in Brazil. However, the role of some species and their relative importance locally in Leishmania Ross 1903 transmission is unclear. The objective of this study was to identify Leishmania infection in phlebotomine sand flies collected around the Lençóis Maranhenses National Park, an important conservation area and popular international/national tourist destination with a high incidence of leishmaniasis. Sand flies were collected in peridomiciliary areas on the tourist route from September 2012 to August 2013. The captured females were subjected to molecular analyses for the detection of Leishmania DNA. Sand flies were infected with four Leishmania species: Leishmania (Viannia) braziliensis (Vianna, 1911) was found in Lutzomyia whitmani (Antunes and Coutinho, 1939) (2.1%) and Lutzomyia longipalpis (Lutz and Neiva, 1912) (1.7%); Leishmania (Leishmania) infantum (Nicole, 1908) infected Lutzomyia wellcomei (Fraiha, Shaw, and Lainson, 1971) (20%), Lutzomyia sordellii (Shannon and Del Ponte, 1927) (4.3%), Lu. longipalpis (3.7%), and Lu. whitmani (0.8%); Leishmania (Leishmania) amazonensis (Lainson & Shaw, 1972) was found in Lu. whitmani (0.58%), while Leishmania (Viannia) lainsoni infected Lutzomyia evandroi (Costa Lima and Antunes, 1936) (3.4%), Lu. longipalpis (1.06%), and Lu. whitmani (0.29%). The occurrence of these parasites requires control measures to reduce the incidence of cutaneous leishmaniasis and to contain a possible epidemic of visceral leishmaniasis, the most severe form of the disease.

Detection of Leishmania DNA and Blood Meal Identification in Sand Flies (Diptera: Psychodidae) From Lençois Maranhenses National Park Region, Brazil.

To elucidate portions of the transmission cycles of American tegumentary leishmaniasis (TL) and visceral leishmaniasis (VL) occurring in the region surrounding the Lençóis Maranhenses National Park, an important tourist center in Brazil, the present study objectives were to determine the rate of natural infection by Leishmania spp. and the blood meal in caught sand flies species in the region. Sand flies were captured over 36 mo in 62 locations of the municipality of Barreirinhas, Maranhão with notifications of disease incidence. Species identification of parasites was performed with internal transcribed spacer 1 (ITS1) PCR-RFLP using HaeIII enzyme. Blood meal identification was performed with cytochrome b (cytb) gene PCR-RFLP using HaeIII and MboI enzyme. The species Lutzomyia longipalpis (Lutz and Neiva 1912) presented a positivity rate of 3.7% for Leishmania infantum. Species not considered vectors of this parasite such as Lu. lenti (Mangabeira 1938) and Lu. whitmani (Antunes & Coutinho 1939) showed infection rates of 0.6% and 0.9%, respectively. Among the vectors of Leishmania spp. was Lu. whitmani with detection rate of 0.3% for Le. braziliensis and Lu. flaviscutellata (Mangabeira 1942) with a detection rate of 8% for Le. amazonensis. After restriction of amplification product encoding a 359bp sequence of the cytb recognized in as follows: pigs (37.9%); dogs (27.4%); chickens (20.9%); horses (9%), rodents (3.3%), and humans (1.4%). The presence of Leishmania DNA in sand flies fed with human blood and domestic animals in villages with transmission of VL and TL suggests that transmission could be occurring in the locations of the infected patients.

Detection of Leishmania amazonensis and Leishmania braziliensis in Culicoides (Diptera, Ceratopogonidae) in an endemic area of cutaneous leishmaniasis in the Brazilian Amazonia.

Biting midges in the genus Culicoides act as vectors of arboviruses throughout the world and as vectors of filariasis in Latin America, the Caribbean, and parts of Africa. Although Culicoides spp. are currently not considered to be vectors of Leishmania protozoa, the high abundance of biting midges in areas with active cutaneous leishmaniasis transmission points to the possibility of Culicoides infection by these pathogens. We used PCR to test captured Culicoides species for natural infection with Leishmania spp. We tested 450 Culicoides females, divided into 30 pools of 15 individuals each, as follows: nine pools of C. foxi (135 specimens), seven pools of C. filariferus (105), seven pools of C. insignis (105), five pools of C. ignacioi (75), and two pools of C. flavivenula (30). PCR confirmed the presence of Leishmania braziliensis DNA in C. ignacioi (0.14%), C. insignis (0.14%), and C. foxi (0.11); and Le. amazonensis DNA in C. filariferus (0.14%) and C. flavivenula (0.50%). We conclude that these Culicoides species can be naturally infected, but vector competence and transmission capability must be confirmed in future studies. Our results warrant further investigation into the role of these biting midge species in the leishmaniasis epidemiological cycle.

An ecological study of sand flies (Diptera: Psychodidae) in the vicinity of Lençóis Maranhenses National Park, Maranhão, Brazil.

BACKGROUND: The Lençóis Maranhenses National Park, located in Maranhão, Brazil, is a region of exceptional beauty and a popular tourist destination. The adjoining area has suffered from the impact of human activity and, consequently, has experienced outbreaks of leishmaniasis. This study aimed to evaluate the composition, abundance, species richness and seasonal distribution of sand flies in the region and to determine the constancy of the insect population. METHODS: The survey was conducted at three sites located in the municipalities of Barreirinhas and Santo Amaro between September 2012 and August 2013. Sampling was performed monthly using automatic light traps installed 1.5 m above the soil adjacent to 13 randomly selected rural dwellings. At each site, one trap was placed in the peridomicile near to animal enclosures and another (extradomicile) at 500 m from the peridomicile. RESULTS: A total of 4,474 individual sand flies were collected over the year with the highest abundance recorded during the rainy season (December to June). Nine species were collected: L. whitmani, L. longipalpis, L. lenti, L. sordellii, L. evandroi, L. flaviscutellata, L. wellcomei, L. termitophila and L. intermedia. Although peridomiciliary and extradomiciliary environments presented similar species richness, the Shannon diversity index was significantly lower in the former (H' = 2.4) compared with the latter (H' = 4.98). Lutzomyia whitmani and L. longipalpis were the most abundant species and were classified as constant (constancy index, CI = 100%) along with L. lenti (CI = 58.3), L. evandroi (CI = 58.3) and L. sordellii (CI = 66.7). The remaining four species presented CI values between 25 and 50% and were considered accessory. CONCLUSIONS: The present results confirm the present of L. whitmani and L. longipalpis in the peridomicile of houses in Lençóis National Park. The abundance of these species could explain, respectively, the endemicity of cutaneous leishmaniasis and sporadic cases of visceral leishmaniasis in the study area. However, in the case of cutaneous leishmaniasis, the presence of other sand fly vectors (in addition to L. whitmani) cannot be neglected. Finally, this study emphasizes the need for a more effective and permanent supervision to control the expansion of these vectors and leishmaniasis outbreaks.

[Occurrence of sand flies (Diptera, Psychodidae) in leishmaniasis foci in an ecotourism area around the Lençóis Maranhenses National Park, Brazil]. / Ocorrência de flebotomíneos (Diptera, Psychodidae) em focos de leishmanioses, em área de ecoturismo do entorno do Parque Nacional dos Lençóis Maranhenses, Brasil.

The distribution and relative abundance of sand fly species were studied in the municipality of Barreirinhas, Maranhão State, Brazil, around the Lençóis Maranhenses National Park, from January to June 2005, August 2004, July 2005, and September/2008. A total of 6,658 specimens were captured. The most frequent species were Lutzomyia whitmani (46.6%), L. longipalpis (29.9%), L. evandroi (17.1%), and L. lenti (4.8%), while L. termitophila, L. flaviscutellata, L. migonei, L. infraspinosa, L. sordellii, L. wellcomei, L. antunesi, and L. trinidadensis represented 1.6%. The presence of Leishmania vector species explains the high detection rate for tegumentary leishmaniasis in 2000 (308.2), 2001 (310.9), 2002 (338.2), and 2005 (313.6) and active foci of human visceral leishmaniasis in the municipality of Barreirinhas.

Ocorrência de flebotomíneos (Diptera, Psychodidae) em focos de leishmanioses, em área de ecoturismo do entorno do Parque Nacional dos Lençóis Maranhenses, Brasil / Occurrence of sand flies (Diptera, Psychodidae) in leishmaniasis foci in an ecotourism area around the Lençóis Maranhenses National Park, Brazil

A freqüência e distribuição das espécies de flebotomíneos foram estudadas no Município de Barreirinhas, Maranhão, Brasil, no entorno do Parque Nacional dos Lençóis Maranhenses, no período de janeiro a junho/2005, agosto/2004, julho/2005 e setembro/2008. Foram capturados 6.658 indivíduos distribuídos em dez espécies. As mais freqüentes foram Lutzomyia whitmani (46,6 por cento), L. longipalpis (29,9 por cento), L. evandroi (17,1 por cento) e L. lenti (4,8 por cento), enquanto L. termitophila, L. flaviscutellata, L. migonei, L. infraspinosa, L. sordellii, L. wellcomei, L. antunesi e L. trinidadensis representaram juntas 1,6 por cento da amostra total. A presença de espécies transmissoras de Leishmania justifica o elevado coeficiente de detecção de leishmaniose tegumentar nos anos de 2000 (308,2), 2001 (310,9), 2002 (338,2) e 2005 (313,6) e focos ativos de leishmaniose visceral humana, no Município de Barreirinhas.

The distribution and relative abundance of sand fly species were studied in the municipality of Barreirinhas, Maranhão State, Brazil, around the Lençóis Maranhenses National Park, from January to June 2005, August 2004, July 2005, and September/2008. A total of 6,658 specimens were captured. The most frequent species were Lutzomyia whitmani (46.6 percent), L. longipalpis (29.9 percent), L. evandroi (17.1 percent), and L. lenti (4.8 percent), while L. termitophila, L. flaviscutellata, L. migonei, L. infraspinosa, L. sordellii, L. wellcomei, L. antunesi, and L. trinidadensis represented 1.6 percent. The presence of Leishmania vector species explains the high detection rate for tegumentary leishmaniasis in 2000 (308.2), 2001 (310.9), 2002 (338.2), and 2005 (313.6) and active foci of human visceral leishmaniasis in the municipality of Barreirinhas.

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.

Preferência alimentar sanguínea de Lutzomyia whitmani (Diptera, Psychodidae) em área de transmissão de leishmaniose cutânea americana, no Estado do Maranhão, Brasil / Blood feeding preference of Lutzomyia whitmani (Diptera, Psychodidae) in a transmission area for American cutaneous leishmaniasis in the State of Maranhão, Brazil

O objetivo deste estudo foi determinar as fontes de alimento sanguíneo de fêmeas de Lutzomyia whitmani, espécie de flebotomíneo incriminada no Maranhão como principal vetor da leishmaniose cutânea americana. Para isso, 70 fêmeas desta espécie coletadas no município de Axixá, área com um dos maiores números de casos de leishmaniose cutânea americana em humanos no Maranhão, foram analisadas utilizando a técnica da precipitina. Dos indivíduos analisados, 90 por cento apresentaram reação a algum tipo de antissoro e dentre estes, 73 por cento apresentaram reações do tipo simples com predominância para sangue de galinha (22,2 por cento), roedor (14,3) e humano (12,7 por cento). Nas reações duplas predominaram as combinações galinha/humano (6,3 por cento), galinha/gambá (4,8 por cento), boi/humano e gambá/humano (3,2 por cento). Assim, concluímos que seres humanos, animais domésticos e sinantrópicos constituem fonte alimentar sanguínea para Lutzomyia whitmani podendo desempenhar um papel importante no ciclo de transmissão da leishmaniose cutânea americana explicando os casos da doença em Axixá.

The aim of this study was to determine the sources of blood meals for females of Lutzomyia whitmani, a phlebotomine species incriminated as the main vector for American cutaneous leishmaniasis in Maranhão. For this, 70 Lutzomyia whitmani females were collected in the municipality of Axixá, an area with one of the greatest numbers of cases of American cutaneous leishmaniasis in humans in Maranhão. They were analyzed using the precipitin technique. Ninety percent of the specimens showed a reaction to some type of antiserum positive immune reaction, among which 73 percent presented single reactions, with predominance for chicken blood (22 percent), rodent blood (14.3 percent) and human blood (12.7 percent). Among the double reactions, the predominant combinations were chicken/human (6.3 percent), chicken/opossum (4.8 percent), ox/human (3.2 percent) and opossum/human (3.2 percent). Thus, we conclude that humans and domestic and synanthropic animals are blood meal sources for Lutzomyia whitmani and may play an important role in the transmission cycle for American cutaneous leishmaniasis, thus explaining the cases of this disease in Axixá.

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.

[Blood feeding preference of Lutzomyia whitmani (Diptera, Psychodidae) in a transmission area for American cutaneous leishmaniasis in the State of Maranhão, Brazil]. / Preferência alimentar sanguínea de Lutzomyia whitmani (Diptera, Psychodidae) em área de transmissão de leishmaniose cutânea americana, no Estado do Maranhão, Brasil.

The aim of this study was to determine the sources of blood meals for females of Lutzomyia whitmani, a phlebotomine species incriminated as the main vector for American cutaneous leishmaniasis in Maranhão. For this, 70 Lutzomyia whitmani females were collected in the municipality of Axixá, an area with one of the greatest numbers of cases of American cutaneous leishmaniasis in humans in Maranhão. They were analyzed using the precipitin technique. Ninety percent of the specimens showed a reaction to some type of antiserum positive immune reaction, among which 73% presented single reactions, with predominance for chicken blood (22%), rodent blood (14.3%) and human blood (12.7%). Among the double reactions, the predominant combinations were chicken/human (6.3%), chicken/opossum (4.8%), ox/human (3.2%) and opossum/human (3.2%). Thus, we conclude that humans and domestic and synanthropic animals are blood meal sources for Lutzomyia whitmani and may play an important role in the transmission cycle for American cutaneous leishmaniasis, thus explaining the cases of this disease in Axixá.

[Feeding preference of sand flies in the Amazon, Maranhão State, Brazil]. / Preferência alimentar sanguínea de flebotomíneos da Amazônia do Maranhão, Brasil.

The objective of this study was to determine the blood feeding sources for sand flies based on the precipitin test in Buriticupu, Amazon Region, Maranhão State, Brazil, from July 2002 to June 2004. Single (87.6%) and double (8%) reactions and non-reactive samples (4.4%) were found. The presence of sand flies fed on human blood (6.7%) and blood of animals that are possible peridomiciliary Leishmania reservoirs helps explain the reporting of autochthonous tegumentary leishmaniasis cases in Buriticupu.

Preferência alimentar sanguínea de flebotomíneos da Amazônia do Maranhão, Brasil / Feeding preference of sand flies in the Amazon, Maranhão State, Brazil

O objetivo deste estudo foi determinar as fontes alimentares sanguíneas de flebotomíneos por meio da reação da precipitina, em Buriticupu, na Amazônia maranhense, Brasil, de julho de 2002 a junho de 2004. Foram detectadas reações simples (87,6 por cento), duplas (8 por cento) e não reagentes (4,4 por cento). A presença de flebotomíneos alimentados com sangue humano (6,7 por cento) e de possíveis reservatórios de Leishmania no peridomicílio ajuda a explicar a ocorrência de casos autóctones de leishmaniose tegumentar no Município de Buriticupu.

The objective of this study was to determine the blood feeding sources for sand flies based on the precipitin test in Buriticupu, Amazon Region, Maranhão State, Brazil, from July 2002 to June 2004. Single (87.6 percent) and double (8 percent) reactions and non-reactive samples (4.4 percent) were found. The presence of sand flies fed on human blood (6.7 percent) and blood of animals that are possible peridomiciliary Leishmania reservoirs helps explain the reporting of autochthonous tegumentary leishmaniasis cases in Buriticupu.

Flebotomíneos (Diptera, Psychodidae) em reservas florestais da área metropolitana de São Luís, Maranhão, Brasil / Phlebotomines (Diptera, Psychodidae) in forest reserves in the metropolitan area of São Luís, Maranhão, Brazil

Estudou-se a diversidade, a abundância relativa e a sazonalidade das espécies de flebotomíneos em duas reservas de floresta primária alterada, a reserva florestal do Sacavém (RFS) e reserva florestal do Itaqui (RFI), localizadas na área metropolitana de São Luís, capital do estado do Maranhão. Os flebotomíneos foram capturados com armadilhas luminosas tipo CDC, instaladas na borda e no centro da mata, a 1,5 metros de altura, das 18h00 às 6h00, uma vez por mês, durante um ano. No total foram capturados 1.356 indivíduos de 23 espécies dos gêneros Lutzomyia (21) e Brumptomyia (2). Na RFS foram capturados 1.061 espécimes, resultando num esforço de captura de 2,5 indivíduos/hora/armadilha e o predomínio de L. longipalpis (44,8 por cento), seguida por L. antunesi (36,4 por cento), L. sordelli (5,9 por cento), L. flaviscutellata (3,9 por cento) e L. whitmani (2,1 por cento). O maior número de espécies (11) e indivíduos (60,1 por cento) ocorreu na estação chuvosa. Na RFI foram obtidos 295 espécimes, o esforço de captura foi 0,2 indivíduos/hora/armadilha, com o predomínio de L. flaviscutellata (58,6 por cento), L. sordelli (14,6 por cento), L. longipalpis (7,1 por cento), L. evandroi (6,4 por cento), L. longipennis (3 por cento), L. trinidadensis (2,7 por cento) e L. whitmani (1,7 por cento). As espécies foram mais numerosas na estiagem (11) e os espécimes durante a estação chuvosa (54,6 por cento).

This study deals with the diversity, relative abundance and seasonality of sandflies species in two modified primary forest fragments, situated at São Luís city, capital of the state of Maranhão. The sandflies were captured with the use of light traps, CDC (Center Control Disease) type, installed at the edge and in the center of the forest, at the height of 1.5 meter, being there from 6 p.m. up to 6 a.m., once per month, during a year time. An amount of 1,356 specimens from 23 species, which 21 belonged to genera Lutzomyia and two belonged to genera Brumptomyia, were captured. In the Sacavém forest reserve, 1,061 specimens were captured, resulting in a capture effort of 2.5 individuals/hour/trap, most of them L. longipalpis (44.8 percent), followed by L. antunesi (36.4 percent), L. sordelli (5.9 percent), L. flaviscutellata (3.9 percent) and L. whitmani (2.1 percent). The highest concentrations of species (11) and individuals (60.1 percent) occurred during the rainy period. In the Itaqui forest reserve, 295 specimens were collected and the capture effort was 0.2 individuals/hour/trap, most of them were L. flaviscutellata, (58.6 percent), L. sordelli (14.6 percent), L. longipalpis (7.1 percent), L. evandroi (6.4 percent), L. longipennis (3 percent), L. trinidadensis (2.7 percent) and L. whitmani (1.7 percent). The species were more frequent during the dry season (11) and specimens during the rainy spell (54.6 percent).

Diagnóstico molecular da taxa de infecção natural de flebotomíneos (Psychodidae, Lutzomyia) por Leishmania sp na Amazônia maranhense / Molecular diagnosis of the natural infection rate due to Leishmania sp in sandflies (Psychodidae, Lutzomyia) in the Amazon region of Maranhão, Brazil

A taxa de infecção natural de três diferentes espécies de flebotomíneos por Leishmania foi estudada usando a técnica de reação em cadeia da polimerase. Primers específicos para Leishmania foram designados para examinar se os pools de flebotomíneos estavam infectadas. Um total de 1.100 fêmeas separadas em pools de 10 indivíduos foram examinados, consistindo de 50 Lutzomyia whitmani, 43 Lutzomyia triacantha e 17 Lutzomyia choti. De todos os pools analisados, 4 de Lutzomyia whitmani estavam positivos, mas nenhum pool das duas espécies restantes estava infectado. Deste modo, uma taxa de infecção de 0,4 por cento foi verificada neste estudo. Esta taxa de infecção associada a estudos anteriores sugere que Lutzomyia whitmani transmite Leishmania aos mamíferos em Buriticupu, Maranhão.

The natural infection rate due to Leishmania was studied in three different sandfly species using the polymerase chain reaction technique. Leishmania specific primers were designed to examine whether sandfly pools were infected. In total 1,100 female sandflies separated into pools of 10 individuals, consisting of 50 pools of Lutzomyia whitmani, 43 of Lutzomyia triacantha and 17 of Lutzomyia choti, were analyzed. Among all the pools examined, four pools of Lutzomyia whitmani were positive, but none of the pools of the other two species were infected. Thus, a total infection rate of 0.4 percent was established in this study. A similar infection rate was found in previous studies, suggesting that Lutzomyia whitmani transmits Leishmania to mammals in Buriticupu, Maranhão.

[Molecular diagnosis of the natural infection rate due to Leishmania sp in sandflies (Psychodidae, Lutzomyia) in the Amazon region of Maranhão, Brazil]. / Diagnóstico molecular da taxa de infecção natural de flebotomíneos (Psychodidae, Lutzomyia) por Leishmania sp na Amazônia maranhense.

The natural infection rate due to Leishmania was studied in three different sandfly species using the polymerase chain reaction technique. Leishmania specific primers were designed to examine whether sandfly pools were infected. In total 1,100 female sandflies separated into pools of 10 individuals, consisting of 50 pools of Lutzomyia whitmani, 43 of Lutzomyia triacantha and 17 of Lutzomyia choti, were analyzed. Among all the pools examined, four pools of Lutzomyia whitmani were positive, but none of the pools of the other two species were infected. Thus, a total infection rate of 0.4% was established in this study. A similar infection rate was found in previous studies, suggesting that Lutzomyia whitmani transmits Leishmania to mammals in Buriticupu, Maranhão.