Leishmania infantum detection in Nyssomyia neivai and dogs in Southern Brazil.

BACKGROUND: The sand fly Nyssomyia neivai is one of the most abundant species in Southern Brazil. It is frequently found in areas that are foci of visceral leishmaniasis in the state of Santa Catarina, caused by Leishmania infantum. In this region, the main vector of L. infantum, Lutzomyia longipalpis, has not been detected. In the absence of L. longipalpis, this study aimed to identify the sand fly fauna and diagnose any potential Leishmania spp. infection in sand flies and in dogs in a region of Southern Brazil that experienced a recent canine visceral leishmaniasis outbreak. METHODS: This report includes a survey of the sand fly fauna at the Zoonosis Control Center of the Municipality of Tubarão (Santa Catarina, Brazil). Molecular tests were conducted to investigate Leishmania spp. natural infection in sand flies using polymerase chain reaction (PCR). In positive females, in addition to morphological identification, molecular analysis through DNA barcoding was performed to determine the sand fly species. Additionally, the dogs were tested for the presence of Leishmania spp. using a non-invasive technique for the collection of biological material, to be assessed by PCR. RESULTS: A total of 3419 sand flies, belonging to five genera, were collected. Nyssomyia neivai was the most abundant species (85.8%), followed by Migonemyia migonei (13.3%), Pintomyia fischeri (0.8%), Evandromyia edwardsi (< 0.1%), and species of the genus Brumptomyia. (0.1%). Out of the 509 non-engorged females analyzed by PCR, two (0.4%) carried L. infantum DNA. The naturally infected females were identified as Ny. neivai, in both morphological and molecular analysis. In addition, two out of 47 conjunctival swabs from dogs tested positive for L. infantum, yielding an infection rate of 4.2%. CONCLUSIONS: These results confirm the presence of Ny. neivai naturally infected with L. infantum in an area where dogs were also infected by the parasite, suggesting its potential role as a vector in Southern Brazil.

The sandfly fauna (Diptera: Psychodidae: Phlebotominae) of the Parque Estadual da Serra da Tiririca, Rio de Janeiro, Brazil.

Cutaneous leishmaniasis (CL) in the state of Rio de Janeiro is sporadic and can be characterised as a peridomestic transmission that occurs in modified natural environments. The aim of this work was to study the fauna and ecological characteristics of sandflies in an environmentally protected area (the State Park of Serra da Tiririca) within the remnants of the Atlantic Forest in the municipalities of Niterói and Maricá and their possible relationship with leishmaniasis. Captures were performed using light traps during the night once a month for one year in both sylvatic environments and areas surrounding homes near the park. A total of 1,037 sandflies were captured, belonging to nine genera and 12 species: Evandromyia tupynambai (34.1%), Migonemyia migonei (20.6%), Brumptomyia cunhai (13.8%), Micropygomyia schreiberi (9.7%), Psathyromyia lanei (6.5%), Brumptomyia nitzulescui (5.7%), Evandromyia edwardsi (5.4%), Nyssomyia intermedia (2.8%), Evandromyia cortelezzii (0.6%), Pintomyia bianchigalatiae (0.5%), Lutzomyia longipalpis (0.2%) and Sciopemyia microps (0.1%). Both Mg. migonei and Ny. intermedia may be acting as vectors of CL in this area.

DNA Barcoding of Neotropical Sand Flies (Diptera, Psychodidae, Phlebotominae): Species Identification and Discovery within Brazil.

DNA barcoding has been an effective tool for species identification in several animal groups. Here, we used DNA barcoding to discriminate between 47 morphologically distinct species of Brazilian sand flies. DNA barcodes correctly identified approximately 90% of the sampled taxa (42 morphologically distinct species) using clustering based on neighbor-joining distance, of which four species showed comparatively higher maximum values of divergence (range 4.23-19.04%), indicating cryptic diversity. The DNA barcodes also corroborated the resurrection of two species within the shannoni complex and provided an efficient tool to differentiate between morphologically indistinguishable females of closely related species. Taken together, our results validate the effectiveness of DNA barcoding for species identification and the discovery of cryptic diversity in sand flies from Brazil.

Peridomiciliary colonies of Triatoma vitticeps (Stal, 1859) (Hemiptera, Reduviidae, Triatominae) infected with Trypanosoma cruzi in rural areas of the state of Espírito Santo, Brazil.

In Brazil, the colonization of human dwellings by triatomines occurs in areas with native vegetation of the caatinga or cerrado types. In areas of Atlantic forest such as in the Brazilian state of Espírito Santo, there are no species adapted to live in human habitations. The few autochthonous cases of Chagas disease encountered in Espírito Santo have been attributed to adult specimens of Triatoma vitticeps that invade houses from forest remnants. In recent years, the entomology unit of the Espírito Santo State Health Secretariat has recorded nymphs infected with flagellates similar to Trypanosoma cruzi in rural localities. Entomological surveys were carried out in the residences and outbuildings in which the insects were found, and serological examinations for Chagas disease performed on the inhabitants. Four colonies were found, all associated with nests of opossums (Didelphis aurita), 111 specimens of T. vitticeps, and 159 eggs being collected. All the triatomines presented flagellates in their frass. Mice inoculated with the faeces presented trypomastigotes in the circulating blood and groups of amastigotes in the cardiac muscle fibres. Serological tests performed on the inhabitants were negative for T. cruzi. Even with the intense devastation of the forest in Espírito Santo, there are no indications of change in the sylvatic habits of T. vitticeps. Colonies of this insect associated with opossum nests would indicate an expansion of the sylvatic environment into the peridomicile.

Peridomiciliary colonies of Triatoma vitticeps (Stal, 1859) (Hemiptera, Reduviidae, Triatominae) infected with Trypanosoma cruzi in rural areas of the state of Espírito Santo, Brazil

In Brazil, the colonization of human dwellings by triatomines occurs in areas with native vegetation of the caatinga or cerrado types. In areas of Atlantic forest such as in the Brazilian state of Espírito Santo, there are no species adapted to live in human habitations. The few autochthonous cases of Chagas disease encountered in Espírito Santo have been attributed to adult specimens of Triatoma vitticeps that invade houses from forest remnants. In recent years, the entomology unit of the Espírito Santo State Health Secretariat has recorded nymphs infected with flagellates similar to Trypanosoma cruzi in rural localities. Entomological surveys were carried out in the residences and outbuildings in which the insects were found, and serological examinations for Chagas disease performed on the inhabitants. Four colonies were found, all associated with nests of opossums (Didelphis aurita), 111 specimens of T. vitticeps, and 159 eggs being collected. All the triatomines presented flagellates in their frass. Mice inoculated with the faeces presented trypomastigotes in the circulating blood and groups of amastigotes in the cardiac muscle fibres. Serological tests performed on the inhabitants were negative for T. cruzi. Even with the intense devastation of the forest in Espírito Santo, there are no indications of change in the sylvatic habits of T. vitticeps. Colonies of this insect associated with opossum nests would indicate an expansion of the sylvatic environment into the peridomicile.

Estudo da fauna flebotomínica (Diptera: Psychodidae: Phlebotominae) no Parque Estadual da Serra da Tiririca, Rio de Janeiro, Brasil / Study on sand flies (Diptera: Psychodidae: Phlebotominae) in Parque Estadual da Serra da Tiririca, Rio de Janeiro, Brazil

Os flebotomíneos são pequenos insetos pertencentes à ordem Diptera, família Psychodidae e subfamília Phlebotominae. São vetores naturais de alguns agentes etiológicos de doenças humanas e de animais. As principais doenças transmitidas pelos flebotomíneos ao homem são as leishmanioses, doenças com diversas manifestações clínicas, causadas por protozoários flagelados do gênero Leishmania. A Leishmaniose Tegumentar Americana no Estado do Rio de Janeiro apresenta em algumas áreas um caráter de transmissão peridomiciliar provocado principalmente pela adaptação de algumas espécies do inseto vetor aos ambientes naturais modificados, acarretando dessa forma o envolvimento de animais domésticos. Os municípios de Niterói e Maricá (RJ) vêm sofrendo um processo de impacto ambiental intenso, por meio da fragmentação das áreas de mata ainda existentes, alterando sua estrutura espacial e transformando-os em municípios com grandes áreas modificadas. O presente trabalho teve como objetivo estudar a fauna e aspectos ecológicos dos flebotomíneos em área de preservação ambiental (Serra da Tiririca), localizada entre os municípios de Niterói e Maricá (RJ), e sua relação com as leishmanioses. Foram realizadas doze coletas, no período de maio de 2010 a maio de 2011, em oito pontos diferentes, tanto em ambiente silvestre como em peridomicílio. Os insetos foram capturados com a utilização de armadilhas luminosas HP (tipo CDC), instaladas aproximadamente a um metro de altura do solo, sempre nos mesmos locais e durante um período mínimo de17 horas, totalizando 204 horas em cada armadilha. No laboratório, foi realizada a triagem dos flebotomíneos coletados, montagem em lâmina e identificação dos mesmos. Foram coletados 1037 flebotomíneos, sendo 552 machos (53,2%) e 485 fêmeas (46,8%), de 9 gêneros e 12 espécies: Evandromyia tupynambai (34,1%), Migonemyia migonei (20,6%), Brumptomyia cunhai (13,8%), Micropygomyia schreiberi (9,7%), Psathyromyia lanei (6,5%), B. nitzulescui (5,7%), E. edwardsi (5,4%), Nyssomyia intermedia (2,8%), E. cortelezzii (0,6%), Pintomyia biachigalatiae (0,5%), Lutzomyia longipalpis (0,2%), Sciopemyia microps (0,1%). Destas, Mi. migonei, Ny. Intermedia e Lu. longipalpis já foram consideradas como vetoras das leishmanioses. Neste trabalho, Mg. migonei foi mais abundante que Ny. intermedia, sugerindo a possibilidade das duas estarem dividindo o papel na transmissão da doença.