Identification of naturally infected Lutzomyia intermedia and Lutzomyia migonei with Leishmania (Viannia) braziliensis in Rio de Janeiro (Brazil) revealed by a PCR multiplex non-isotopic hybridisation assay

Abstract

To identify naturally infected Lutzomyia spp. by Leishmania (Viannia) braziliensis, a PCR multiplex non-isotopic hybridisation assay was developed for the analysis of insect samples collected in distinct areas of the municipality of Rio de Janeiro (Brazil), from March to December 2003. Data from experimental infection indicate that the method can detect one individual infected insect out of ten. Wild sand flies were classified and grouped into pools of 10 specimens each, reaching a total of 40 female groups. Positive results were obtained with pools of Lu. intermedia (5/32) and Lu. migonei (3/5) collected in two areas from the district of Jacarepaguá presenting recent cases of human and canine leishmaniasis. Considering eight infected groups (8/40) with at least one positive insect in each, it was possible to infer an infection rate of 2%. This technique permits the synchronous processing of a large number of samples, in order to investigate infection rates in sand fly populations and to identify potential insect vectors. The results presented here represent the first molecular approach used to infer the natural infection index in both Lutzomyia spp. and constitute essential data to the understanding of leishmaniasis ecoepidemiology in endemic areas from Rio de Janeiro.

Sandflies (Diptera: Psychodidae) in rural and urban environments in an endemic area of cutaneous leishmaniasis in southern Brazil

“…fischeri naturally infected with Leishmania braziliensis has only recently been found in the Southeast Region of Brazil (Margonari et al 2010, Rocha et al 2010, but the other species have all been found naturally infected by Leishmania (Viannia) sp. in PR and in other areas of South America (de Queiroz et al 1994, da Silva & Grunewald 1999, Luz et al 2000, Pita-Pereira et al 2005, 2009 residence of an American cutaneous leishmaniasis (ACL) case; 2.1: tree close to the veranda of home; 2.2: peridomicile, avocado tree used as a perch for birds; 2.3: peridomicile, tree close to pigsty; 3: residence of an ACL case; 3.1: peridomicile in a jaboticaba tree close to the home; 3.2: orange tree close to the pigsty and residence; 3.3: bamboo, distant 10 m from the residence, next to a pasture, a pound and a small forest; 4.1: pigsty close to the residence; 4.2: pigsty situated at the forest edge, 50 m far from the residence; 4.3: forest edge tree (50 m far the point 4.2); F: female; M: male.…”

Flebótomos de áreas com ocorrências de casos humanos de leishmaniose tegumentar americana no Município de Seropédica, Estado do Rio de Janeiro

“…A Lutzomyia intermedia, pré-adaptada ao ambiente alterado, passou a ser considerado vetor potencial desta protozoose 19 22 acompanhada, mais recentemente no município do Rio de Janeiro pela Lutzomyia migonei 19 .…”

“…Parasitos foram colhidos em fase logarítmica e lavados em PBS antes do isolamento do DNA. Depois solução tampão de lise contendo fenol clorofórmio e precipitação do etanol, como descritas acima para amostras dos insetos de acordo com Pita-Pereira 19 . …”

Sandflies (Diptera: Psychodidae) in an urban area of Northeastern Brazil

“…Its presence inside the homes and outdoors indicates its adaptation to human environments (5) (29) . L. migonei was found naturally infected in the municipality of São Vicente Ferrer, Pernambuco (5) and in the State of Rio de Janeiro (6) (7) . However, its role in the epidemiology of VL in Brazil needs to be elucidated.…”

“…In Brazil, two species are involved in transmission of visceral leishmaniasis (VL), namely Lutzomyia longipalpis and Lutzomyia cruzi (4) . Lutzomyia migonei specimens were found to be naturally infected with Leishmania infantum, in São Vicente Ferrer, Pernambuco (5) and Rio de Janeiro (6) (7) . An experimental infection with L. infantum was reported in a previous study (8) .…”