Study of phlebotomine sand flies (Diptera: Psychodidae) collected in a Leishmania-endemic area of the metropolitan region of Belo Horizonte, Brazil.

Phlebotomine sand flies are distributed across nearly all faunal regions of the world, represented by over 800 species, of which many are important vectors of human pathogens. Brazil is currently faced with the expansion and urbanization of leishmaniases, with an increase in the numbers of human cases and seropositive dogs in various medium-sized to large cities. The objective of the current study was to survey the phlebotomine sand fly species in an area endemic for American cutaneous leishmaniasis (ACL) and American visceral leishmaniasis (AVL), i.e., the municipal district of Santa Luzia, lying within the metropolitan region of Belo Horizonte in the Brazilian State of Minas Gerais. Sand flies were collected monthly in 2004-2005 using modified Falcão light traps hung in the peridomiciles of houses and surrounding wooded areas in the district of Baronesa. A total of 1,552 sand flies belonging to seven species was collected, and an interesting pattern of the distribution of the most abundant species relative to the sampling locality was revealed. In the wooded areas Lutzomyia whitmani (Antunes & Coutinho) predominated, whereas in the urban area Lutzomyia longipalpis (Lutz & Neiva) was the most abundant species. These results indicate two possible epidemiological patterns of Leishmania transmission in Santa Luzia: one for American cutaneous leishmaniasis associated predominantly with wooded areas, and another for AVL, with transmission principally occurring around human habitations.

Distribuição geográfica do complexo cortelezzii (Diptera: Psychodidae: Phlebotominae) no Brasil / Geographical distribution of the cortelezzii (Diptera: Psychodidae: Phlebotominae) complex in Brazil

There are nearly 500 species of sandflies in Americas, 30 of which are vectors of leishmaniasis. Evandromyia cortelezzii (Brèthes), E. sallesi (Galvão & Coutinho) and E. corumbaensis (Galati et al) comprise the cortelezzii complex. These species are morphologically similar and many times misidentified. Due to the epidemiological importance recently attributed to this complex, a detailed study was carried out in order to correct wrongful information due to their misidentification, and update their geographical distribution. Evandromyia corumbaensis was found to have a regional distribution, while the other two species are widely distributed in the Brazilian territory.

Existem aproximadamente 500 espécies de flebotomíneos nas Américas, sendo 30 delas vetores de leishmanioses. Evandromyia cortelezzii (Brèthes), E. sallesi (Galvão & Coutinho) e E. corumbaensis (Galati et al) formam o complexo cortelezzii. Essas espécies são semelhantes morfologicamente e muitas vezes confundidas, gerando erros em sua identificação específica. Devido à importância epidemiológica recentemente atribuída a esse complexo, foi realizado estudo detalhado a fim de corrigir as impropriedades cometidas durante a identificação específica das mesmas e atualizar sua distribuição geográfica. Evandromyia corumbaensis tem distribuição regional, enquanto as demais estão amplamente distribuídas pelo território brasileiro.

Natural infection of Lutzomyia neivai and Lutzomyia sallesi (Diptera: Psychodidae) by Leishmania infantum chagasi in Brazil.

Natural infections with Leishmania were found in females of the phlebotomine sand flies Lutzomyia neivai (Pinto) (= Nyssomyia neivai) and Lutzomyia sallesi (Galvão & Coutinho) (= Evandromyia sallesi) (Diptera: Psychodidae) from Lassance, in the Brazilian state of Minas Gerais. Promastigotes were found in the pyloric region of the former species and in the abdominal midgut of the latter species. Insects found to be infected by microscopic examination were macerated in saline solution and inoculated into hamsters. Subsequent analysis by polymerase chain reaction-restriction fragment length polymorphism revealed both isolates to belong to the species Leishmania infantum chagasi Cunha & Chagas.

[Geographical distribution of the cortelezzii (Diptera: Psychodidae: Phlebotominae) complex in Brazil]. / Distribuição geográfica do complexo cortelezzii (Diptera: Psychodidae: Phlebotominae) no Brasil.

There are nearly 500 species of sandflies in Americas, 30 of which are vectors of leishmaniasis. Evandromyia cortelezzii (Brèthes), E. sallesi (Galvão & Coutinho) and E. corumbaensis (Galati et al) comprise the cortelezzii complex. These species are morphologically similar and many times misidentified. Due to the epidemiological importance recently attributed to this complex, a detailed study was carried out in order to correct wrongful information due to their misidentification, and update their geographical distribution. Evandromyia corumbaensis was found to have a regional distribution, while the other two species are widely distributed in the Brazilian territory.

Naturally infected Lutzomyia sand flies in a Leishmania-endemic area of Brazil.

In Brazil, Leishmania transmission involves several species of phlebotomine sand flies that are closely associated with different parasites and reservoirs, giving rise to different transmission cycles. The present study focused on naturally infected phlebotomines originating from Santa Luzia, a municipality near Belo Horizonte, capital of the Brazilian state of Minas Gerais, in which leishmaniasis are endemic. Systematic and non systematic approaches,involving the use of light traps and direct aspiration from resting sites, respectively, were used to collect females and flies. Identification of the captured insects and determination of natural infection by Leishmania spp. were performed using both conventional dissection methods and polymerase chain reaction (PCR). The dissection of 102 sand flies allowed five species of Lutzomyia to be identified, although no flagellate parasite forms were observed.In addition, 211 sand flies were identified, were separated according to species, and were combined into 11 pools of up to 20 individuals each. PCR analyses showed that two of these pools were infected with Leishmania:one pool of Lu. whitmani was infected with Le. (Viannia) spp. and another of Lu. cortelezzii was infected with Le. chagasi. This suggests that Lu. whitmani may be a possible vector of Leishmania in the study area, and more work needs to be performed to assess the role of Lu. cortelezzii as a vector.