Lutzomyia migonei is a permissive vector competent for Leishmania infantum.

BACKGROUND: Leishmania infantum is the most widespread etiological agent of visceral leishmaniasis (VL) in the world, with significant mortality rates in human cases. In Latin America, this parasite is primarily transmitted by Lutzomyia longipalpis, but the role of Lutzomyia migonei as a potential vector for this protozoan has been discussed. Laboratory and field investigations have contributed to this hypothesis; however, proof of the vector competence of L. migonei has not yet been provided. In this study, we evaluate for the first time the susceptibility of L. migonei to L. infantum. METHODS: Females of laboratory-reared L. migonei were fed through a chick-skin membrane on rabbit blood containing L. infantum promastigotes, dissected at 1, 5 and 8 days post-infection (PI) and checked microscopically for the presence, intensity and localisation of Leishmania infections. In addition, morphometric analysis of L. infantum promastigotes was performed. RESULTS: High infection rates of both L. infantum strains tested were observed in L. migonei, with colonisation of the stomodeal valve already on day 5 PI. At the late-stage infection, most L. migonei females had their cardia and stomodeal valve colonised by high numbers of parasites, and no significant differences were found compared to the development in L. longipalpis. Metacyclic forms were found in all parasite-vector combinations since day 5 PI. CONCLUSIONS: We propose that Lutzomyia migonei belongs to sand fly species permissive to various Leishmania spp. Here we demonstrate that L. migonei is highly susceptible to the development of L. infantum. This, together with its known anthropophily, abundance in VL foci and natural infection by L. infantum, constitute important evidence that L. migonei is another vector of this parasite in Latin America.

Molecular detection of Leishmania in phlebotomine sand flies in a cutaneous and visceral leishmaniasis endemic area in northeastern Brazil.

Several phlebotomine sand fly species have been regarded as putative or proven vectors of parasites of the genus Leishmania in Brazil, but data for the northeastern region remains incipient. In this study, a total of 600 phlebotomine sand flies were grouped in pools of 10 specimens each and tested by a Leishmania genus-specific PCR and by a PCR targeting Leishmania (Leishmania) infantum. Fourteen out of 60 pools were positive by the genus-specific PCR, being five pools of L. migonei, seven of L. complexa, one of L. sordellii and one of L. naftalekatzi, which correspond to a minimal infection rate of 2.3% (14/600). Our results, associated with their known anthropophily and their abundance, suggest the participation of L. migonei and L. complexa as vectors of Leishmania in northeastern Brazil. Remarkably, this is the first time in this country that the detection of Leishmania DNA in L. sordellii and L. naftalekatzi has been reported, but future studies are necessary to better understand the significance of these findings.

Ecology of Lutzomyia longipalpis in an area of visceral leishmaniasis transmission in north-eastern Brazil.

Visceral leishmaniasis is a major public health issue in South America, where the disease is rapidly spreading. Changes in ecology and distribution of the principal vector, Lutzomyia longipalpis are among the factors accounting for the increasing incidence of the disease in this region. However, information about the ecology of L. longipalpis is still incipient, which may directly impair the implementation of effective control programs. Herein, the ecology of L. longipalpis was studied in a focus of visceral leishmaniasis in north-eastern Brazil. From August 2009 to August 2010, phlebotomine sand flies were monthly collected in four localities using CDC light traps (~37 per month) and a lantern-baited Shannon trap with mouth aspirators. A total of 24,226 phlebotomine sand flies were collected with light traps and 375 with mouth aspirators. The most abundant species was L. longipalpis, representing 97.9% of the specimens collected with light traps and 91.5% with the mouth aspirator. Other species (Lutzomyia evandroi, Lutzomyia lenti and Lutzomyia sallesi) were found in low numbers. Most phlebotomine sand flies (94.6%) were collected at chicken coops and corrals. No significant correlation was found between the monthly abundance of phlebotomine sand flies and the monthly averages of temperature, relative humidity or rainfall. However, interestingly enough, 82.4% of L. longipalpis specimens were collected in months when relative humidity surpassed 75%. This study points out that this vector is well adapted to live in different habitats and to different climate conditions. It also suggests that some north-eastern populations of L. longipalpis may be more xerotolerant than southern populations. Further studies to assess the relationship between microclimate and L. longipalpis density in different Brazilian regions are advised.

Phlebotomine sandflies (Diptera: Psychodidae) in São Vicente Férrer, a sympatric area to cutaneous and visceral leishmaniasis in the state of Pernambuco, Brazil.

INTRODUCTION: In the last decades, a considerable geographic expansion of the leishmaniases in all regions of Brazil has been observed. The present study was carried out to identify the composition of the phlebotomine sandfly fauna and verify the seasonal variation of the main species after environmental changes occurred in São Vicente Férrer Municipality, State of Pernambuco, Brazil. METHODS: Captures were carried out during four consecutive nights of each month using Centers for Disease Control and Prevention light traps from September 2009 to September 2010. The correlation between the number of phlebotomine sandflies captured and climatic factors (temperature and rainfall) was evaluated. RESULTS: A total of 13,872 specimens belonging to 20 species were captured, of which, 6,247 (45%) were females, and 7,625 (55%) were males. Lutzomyia migonei was the most abundant species with 9,964 (71.8%) specimens, being predominant in the intradomicile and peridomicile areas with 108 (86.4%) and 9,746 (97%), respectively. In the forest remnants, Lutzomyia complexa 2,395 (65%) and Lutzomyia sordellii 770 (20.8%) predominated. The correlation analysis between the total number of sandflies captured and climatic factors did not show a significant influence on population density. CONCLUSIONS: The high abundance of Lutzomyia migonei and Lutzomyia complexa indicates the possibility of new cases of cutaneous leishmaniasis (CL).

Phlebotomine sandflies (Diptera: Psychodidae) in São Vicente Férrer, a sympatric area to cutaneous and visceral leishmaniasis in the state of Pernambuco, Brazil / Flebotomíneos (Diptera: Psychodidae) em São Vicente Férrer, uma área simpátrica para leishmaniose tegumentar e visceral, no estado de Pernambuco, Brasil

INTRODUCTION: In the last decades, a considerable geographic expansion of the leishmaniases in all regions of Brazil has been observed. The present study was carried out to identify the composition of the phlebotomine sandfly fauna and verify the seasonal variation of the main species after environmental changes occurred in São Vicente Férrer Municipality, State of Pernambuco, Brazil. METHODS: Captures were carried out during four consecutive nights of each month using Centers for Disease Control and Prevention light traps from September 2009 to September 2010. The correlation between the number of phlebotomine sandflies captured and climatic factors (temperature and rainfall) was evaluated. RESULTS: A total of 13,872 specimens belonging to 20 species were captured, of which, 6,247 (45 percent) were females, and 7,625 (55 percent) were males. Lutzomyia migonei was the most abundant species with 9,964 (71.8 percent) specimens, being predominant in the intradomicile and peridomicile areas with 108 (86.4 percent) and 9,746 (97 percent), respectively. In the forest remnants, Lutzomyia complexa 2,395 (65 percent) and Lutzomyia sordellii 770 (20.8 percent) predominated. The correlation analysis between the total number of sandflies captured and climatic factors did not show a significant influence on population density. CONCLUSIONS: The high abundance of Lutzomyia migonei and Lutzomyia complexa indicates the possibility of new cases of cutaneous leishmaniasis (CL).

INTRODUÇÃO: Nas últimas décadas tem se observado uma considerável expansão geográfica das leishmanioses em todas as regiões do Brasil. O presente estudo foi realizado para identificar a fauna de flebotomíneos e verificar a sazonalidade das principais espécies após mudanças ambientais ocorridas no município de São Vicente Férrer, Estado de Pernambuco, Brasil. MÉTODOS: As capturas foram realizadas durante quatro noites consecutivas por mês usando armadilhas luminosas CDC, no período de setembro de 2009 a setembro de 2010. A correlação entre o número de flebotomíneos capturados e fatores climáticos (temperatura e umidade) foi avaliada. RESULTADOS: Foi capturado um total de 13.872 espécimes pertencentes a 20 espécies, sendo 6.247 (45 por cento) fêmeas e 7.625 (55 por cento) machos. Lutzomyia migonei foi a espécie mais abundante com 9.964 (71,8 por cento) espécimes, sendo predominante no intradomicílio 108 (86,4 por cento) e peridomicílio 9.746 (97 por cento). Nos resquícios de mata primária, predominaram Lutzomyia complexa 2.395 (65 por cento) e Lutzomyia sordellii 770 (20,8 por cento). A análise de correlação entre o número total de flebotomíneos capturados e os fatores climáticos não mostrou uma influência significativa na densidade da população. CONCLUSÕES: A elevada abundância de Lutzomyia migonei e Lutzomyia complexa indica a possibilidade de novos casos de leishmaniose cutânea (LC).

Avaliação da susceptibilidade de Lutzomyia migonei (Diptera: Psychodidae) ao desenvolvimento de Leishmania (Leishmania) infantum

Leishmania (Leishmania) infantum é o agente etiológico da leishmaniose visceral (LV) mais disseminado no mundo, com taxas de mortalidade significativas em casos humanos. Na América Latina, este parasito é transmitido principalmente por Lutzomyia longipalpis, entretanto, o papel de Lutzomyia migonei como um potencial vetor deste protozoário tem sido discutido. Investigações laboratoriais e de campo têm contribuído para esta hipótese, no entanto, a prova da competência vetorial de L. migonei ainda não foi fornecida. Neste estudo, foi avaliada pela primeira vez a susceptibilidade de L. migonei para duas cepas de L. (L.) infantum e realizada a comparação com o desenvolvimento em L. longipalpis. A colônia de L. migonei foi estabelecida na Faculdade de Ciências da Charles University em Praga, República Theca de espécimes capturados no município de Baturité, estado do Ceará...

Leishmania (Leishmania) infantum is the most widespread etiological agent of visceral leishmaniases (VL) in the world, with significant mortality rates in human cases. In Latin America, this parasite is primarily transmitted by Lutzomyia longipalpis, but the role of Lutzomyia migonei as a potential vector for this protozoan has been discussed. Laboratory and field investigations have contributed to this hypothesis. However, proof of the vector competence of L. migonei has not yet been provided. In this study, we evaluate for the first time the susceptibility of L. migonei to two L. (L.) infantum strains and compared with development of L. longipalpis. Colony of L. migonei was established at Faculty of Science, Charles University in Prague from specimens captured in Baturité municipality, Ceará state...

Avaliação da infecção natural de flebotomíneos (Diptera: Psychodidae) por Leishmania spp. no município de São Vicente Férrer, Pernambuco / Evaluation of natural infection of sand flies (Diptera: Psychodidae) with Leishmania spp. in the municipality of San Vicente Ferrer, Pernambuco

Nas últimas décadas, tem se observado uma considerável expansão geográfica das leishmanioses em todas as regiões do Brasil. Em Pernambuco, São Vicente Férrer localizado na Zona da Mata Norte do Estado, se destaca pela ocorrência de ambas as formas da doença. De 1999 a 2010 foram registrados 157 casos autóctones de leishmaniose tegumentar americana (LTA) e 15 de leishmaniose visceral americana (LVA). Este estudo objetivou avaliar a infecção natural de flebotomíneos por Leishmania spp. As capturas foram realizadas no período entre setembro de 2009 e setembro de 2010, com armadilhas luminosas tipo CDC, entre 18:00h e 6:00h, durante quatro noites consecutivas de cada mês, dispostas em diferentes ecótopos: no intradomicílio, peridomícilio e resquícios de mata primária. Adicionalmente, foram realizadas capturas com capturador manual de Castro com o auxílio da armadilha de Shannon. Os espécimes capturados foram identificados de acordo com a classificação proposta por Young e Duncan (1994). Foram formados grupos contendo 10 fêmeas separadas por espécie, para extração e detecção de DNA do parasito através de dois sistemas de PCR, sendo um específico para o complexo Leishmania braziliensis (subgênero Viannia) e o outro para complexo donovani (Leishmania infantum). Foram capturados 13.872 flebotomíneos pertencentes a 20 espécies. L. migonei foi a espécie mais abundante, com 9.964 exemplares (71 por cento) da fauna, a qual estava presente em todos os ecótopos investigados, com predominância no intradomicílio e peridomicílio. Nos resquícios de mata, as espécies mais frequentes foram L. complexa (65 por cento) e L. sordellii (20,8 por cento). As taxas de infecção natural encontradas foram: L. migonei (2,1 por cento), L. complexa (0,5 por cento), L. sordellii (5,1 por cento) e L. walkeri (50 por cento), sendo todas para a Leishmania (Viannia) spp...

In the latest decades, has been observed a considerable geographic distribution of leishmaniasis in all regions of Brazil. São Vicente Ferrer, located in the northern Zona da Mata of Pernambuco State, is distinguished for occurrence of both manifestations of the disease. From 1999 to 2010, 157 autochthonous cases of American Cutaneous Leishmaniais (ACL) and 15 of American Visceral Leishmaniasis (VL) have been registered. The objective of this study was to evaluate the phlebotominae natural infection by Leishmania spp. The collected were carried from September 2009 to September 2010 with Centers for Disease Control and Prevention (CDC) light traps, from 6:00 pm to 6:00 am, during four successive nights distributed inside houses, peridomicile areas and forest patches. Additionally, were carried collections with Castro catcher and through Shannon trap. The specimens were identified according the classification proposed by Young & Duncan (1994). Pools containing 10 females separated by species were submitted to DNA extraction and detection of parasite by two differents systems of PCR, one specific for the Leishmania braziliensis complex (subgenus Viannia) and other for donovani complex (Leishmania infantum). A total of 13.872 sand flies belonging the twenty species were captured, with predominance of L. migonei, which presented 9,964 specimens (71%), being founded in all investigated ecotopes, with predominance inside houses and peridomicile areas. In the forest patches, the species more frequent were L. complexa (65%) and L. sordellii (20,8%). The rates of natural infection by Leishmania (Viannia) spp. were: L. migonei (2,1%), L. complexa (0,5%), L. sordellii (5,1%) and L. walkeri (50%)...