Vectors phlebotomines and prevalence of the canine visceral Leishmaniosis in endemic area of the city of Santa Luzia, metropolitan region of Belo Horizonte, Minas Gerais/Brazil

Made available in DSpace on 2012-05-07T15:26:23Z (GMT). No. of bitstreams: 2 license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) 000009.pdf: 1751449 bytes, checksum: ac81ddcdfe698ad73e50c728791a4983 (MD5) Previous issue date: 2006Fundação Oswaldo Cruz. Centro de Pesquisas René Rachou. Belo Horizonte, MG, Brasil.O Brasil enfrenta atualmente a expansão e urbanização das leishmanioses com um grande número de casos humanos e cães positivos em várias cidades de grande e médio porte. A ocorrência da doença em uma determinada área depende basicamente da presença do vetor susceptível e de um hospedeiro/reservatório igualmente susceptível. O presente trabalho avaliou aspectos epidemiológicos das leishmanioses relacionados à infecção canina e aos flebotomíneos em uma área endêmica do município de Santa Luzia/MG, com registros recentes de casos humanos autóctones de LVA e LTA. Foram realizadas coletas sistematizadas mensais durante um ano, utilizando armadilhas luminosas de Falcão e não sistematizadas, com capturas manuais utilizando o capturador de Castro. As fêmeas capturadas foram identificadas e destinadas à verificação de infecção natural através da dissecção e detecção de DNA do parasito (PCR) em “pools” específicos contendo até 20 fêmeas cada. A densidade total de flebotomíneos foi correlacionada com dados climatológicos. No estudo da infecção canina foi verificada a soroprevalência, prevalência da infecção e da doença nos cães, utilizando técnicas sorológicas (RIFI e ELISA) e moleculares (PCR) para o diagnóstico. Foram utilizadas na PCR amostras clínicas de pele, medula óssea (de 43 cães sorologicamente positivos) e sangue periférico (202 cães). O isolamento e caracterização do parasito foram realizados utilizando amostras positivas da cultura de aspirado de medula óssea e amostras clínicas positivas dos 43 cães reativos na sorologia. Foi coletado um total de 1552 exemplares, sendo 1154 machos e 398 fêmeas, pertencentes a sete espécies de flebotomíneos, sendo a mais abundante a Lutzomyia whitmani (75%) seguida por L. longipalpis (19%), que são vetoras da LTA e LVA respectivamente. Não foi observada nenhuma correlação estatisticamente significativa entre a densidade total de flebotomíneos e os dados climatológicos durante o período de estudo. Foram dissecadas 102 fêmeas pertencentes a cinco espécies e em nenhuma foi observada a presença de formas flageladas. Para a detecção através da PCR foram constituídos 11 “pools” a partir de 211 fêmeas vivas, pertencentes a cinco espécies. Em dois “pools” foi possível verificar infecção natural, sendo um de L. whitmani, infectado por L. braziliensis e um de L. cortelezzii infectado por L. chagasi. Estes resultados sugerem a possível participação de L. whitmani na transmissão da LTA na área de estudo e a necessidade de estudos mais aclaradores sobre o envolvimento de L. cortelezzii no ciclo de transmissão da LVA. No estudo da infecção canina a L. chagasi foi a espécie responsável pela LVC no Bairro Baronesa, Santa Luzia/MG. A soroprevalência, prevalência da infecção e da doença nos cães foi de 57, 54 e 16% respectivamente. A alta soroprevalência e a baixa prevalência da doença encontrada nos nossos resultados ilustram o grande problema enfrentado atualmente no diagnóstico clínico e sorológico da LVC, com uma grande quantidade de cães assintomáticos (159/201 no nosso estudo) e de diagnósticos falsopositivos (37/201) e falso-negativos (30/201). Sobre as amostras clínicas utilizadas na PCR (pele, medula óssea e sangue) podemos dizer que a amostra de sangue foi a menos eficiente no grupo dos 43 cães com sorologia positiva, entretanto esta apresentou resultados semelhantes aos observados com os métodos sorológicos na amostragem de 202 cães. Outra observação importante foi a positividade apresentada pelas amostras de pele e sangue independente da sintomatologia dos cães (P>0,05), ao contrário do que foi verificado para a medula, com um número maior de cães positivos (87%) no grupo dos assintomáticos (P<0,05). Assim, a alta prevalência da infecção canina e a presença predominante e abundante de espécies de flebotomíneos vetoras apresentadas nos nossos resultados podem clarear a escolha das medidas de controle mais adequadas à situação atual, pelos órgãos competentes do município. De fato há que se valorizar e incentivar novas investigações e pesquisas aplicadas como fontes importantes de informações para subsidiar o Programa de Controle das Leishmanioses no Brasil.At present, Brazil is facing an increased urbanization of leishmaniases with a high number of human and canine cases in several cities. The occurrence of leishmaniasis is basically determined by the presence of both a susceptible vector and a host/reservoir equally susceptible to the infection. The present investigation sought to assess leishmaniases epidemiological aspects related with the canine infection and phlebotomine sand flies in an endemic area in the municipality of Santa Luzia, state of Minas Gerais. Recent autochthonous human cases of American cutaneous leishmaniasis (ACL) and visceral leishmaniasis (VL) have been reported in this area. Monthly sand fly collections were carried out throughout one year by means of Falcão Light Traps. During the same period, non-systematized collections were manually performed through suction tube. Female phlebotomine sand flies were identified and submitted to a natural infection assessment through dissection and parasite DNA detection by polymerase chain reaction (PCR) in specific pools including up to 20 female sand flies. The total density of phlebotomine has been correlated with climate data. In the study on canine infection, seroprevalence, prevalence of infection and the canine disease were determined by means of serological (RIFI and ELISA) and molecular (PCR) techniques. For PCR procedures, clinical samples included: skin and bone marrow from 43 serologically positive dogs and peripheral blood from 202 dogs. Parasite isolation and characterization were carried out by using positive samples from cultures of bone marrow aspirates and positive clinical samples from 43 serologically reactive dogs. A total of 1552 specimens were collected, 1154 males and 398 females, belonging to seven phlebotomine species, being the most frequent Lutzomyia whitmani (75%), followed by L. longipalpis (19%), which are ACL and VL vectors, respectively. No statistically significant correlation was observed between the total density of phlebotomine sand flies and climate data during the period of the present investigation. After dissecting a number of 102 females, belonging to five different species,no flagellate forms were found. As for PCR, the number of 211 live females, belonging to five species, comprised 11 pools for the parasite DNA detection. In two pools, natural infection was observed: one pool of L. whitmani, infected with L. braziliensis and, one pool of L. cortelezzii infected with L. chagasi. Such results suggest a likely participation of L. whitmani in ACL transmission in the area under study, requiring further investigation on the participation of L. cortelezzii in the VL transmission cycle. In the study on canine infection, L. chagasi showed to be responsible for VL in the local district of Baronesa, in Santa Luzia. Seroprevalence, prevalence of infection and the canine disease were 57%, 54% and 16%, respectively. The high seroprevalence and low prevalence of the canine disease found in the present study mirror one of the biggest difficulties to be overcome nowadays regarding VL clinical and serological diagnoses: a high number of asymptomatic dogs (159/201), falsepositive dogs (37/201) and false-negative animals (30/201). Concerning clinical samples used for PCR (skin, bone marrow and peripheral blood), although blood has provided to be less efficient in positive serology, for the group of 43 dogs, it has shown similar results with serological techniques in the sampling of 202 animals. Another important remark concerns the positivity degree shown by skin and blood samples, regardless the symptomatology of the dogs (P>0.05); differently from that shown by bone marrow samples with higher positivity (87%) in the group of asymptomatic dogs (P<0.05). Thus, the high prevalence of canine infection and the predominant and abundant presence of phlebotomine sand fly vectors shown here may provide helpful data to design control measures that would be more suitable for the present condition in the municipality. Indeed, further investigation and applied research should be valued and supported in order to have important information provided for the implementation of the Leishmaniases Control Program in Brazil

Bilateral anomaly in the style of Micropygomyia schreiberi (Martins, Falcão & Silva) (Diptera, Psychodidae) Anomalia bilateral no dististilo de Micropygomyia schreiberi (Martins, Falcão & Silva) (Diptera, Psychodidae)

This paper presents a specimen of phlebotomine sand fly with a bilateral anomaly in the style. Although such anomaly be rare in this group of insects, it may cause confusion in taxonomic identification and even lead to description of new species, increasing the number of synonymies. The specimen was measured and compared with the holotype and four paratypes of Micropygomyia schreiberi (Martins, Falcão & Silva, 1975) and confirmed that it belongs, in fact, to this species.<br>Este trabalho relata o encontro de um flebotomíneo com anomalia bilateral no dististilo. Esta anomalia é rara neste grupo de insetos e pode causar confusão na identificação específica e levar à descrição de novas espécies, aumentando a lista de sinonímia do grupo. O espécime foi medido e comparado com o holótipo e quatro parátipos de Micropygomyia schreiberi (Martins, Falcão & Silva, 1975) e concluímos que, de fato, se trata desta espécie

Bilateral anomaly in the style of Micropygomyia schreiberi (Martins, Falc\ue3o &amp; Silva) (Diptera, Psychodidae)

This paper presents a specimen of phlebotomine sand fly with a bilateral anomaly in the style. Although such anomaly be rare in this group of insects, it may cause confusion in taxonomic identification and even lead to description of new species, increasing the number of synonymies. The specimen was measured and compared with the holotype and four paratypes of Micropygomyia schreiberi (Martins, Falcão &amp; Silva, 1975) and confirmed that it belongs, in fact, to this species

Sandflies (Diptera: Psychodidae: Phlebotominae) collected on the banks of the Velhas River in the state of Minas Gerais, Brazil

Leishmaniases are endemic to several Brazilian states, including Minas Gerais. As many cases of these diseases are diagnosed in Minas Gerais every year, this paper aimed to determine the diversity of the species of sandflies vector of leishmaniases, in Lassance and Corinto on the banks of the Velhas River. Over two years, 21,014 specimens of sandflies, belonging to 19 species were captured with light traps. Of these specimens, Nyssomyia neivai (Pinto 1926) (84.18%), Nyssomyia intermedia (Lutz &amp; Neiva 1912) (13.41%), Evandromyia lenti(Mangabeira 1938) (0.99%) and Evandromyia sallesi (Galvão &amp; Coutinho 1939) (0.48%) were the most represented. The former two species could be involved in the epidemiological chain of leishmaniasis in this region. No significant difference was found between the species compositions on the two river banks

Description of a new phlebotomine species, Martinsmyia reginae sp. nov. (Diptera: Psychodidae: Phlebotominae) from a cave in the state of Tocantins Brazil

As inhabitants of forested areas, caves and anthropic environments, the phlebotomines deserve special attention because some species are able to transmit trypanosomatids, bacteria and viruses to vertebrates. Phlebotomines are also a nuisance because they cause painful bites, which may ultimately produce allergic manifestations. The lack of information about the presence and behaviours of sand flies in caves has aroused the curiosity of researchers for a long time. In the present paper, we describe a new species of sand fly that was captured in a cave located in the municipal district of Arraias in the southeastern region of the state of Tocantins. The morphological features of this new species permit it to be included in the alphabetica group of the Martinsmyia genus

Natural Leishmania sp. reservoirs and phlebotomine sandfly food source identification in the Ibitipoca State Park, Minas Gerais, Brazil

Submitted by Nuzia Santos ([email protected]) on 2014-06-24T18:32:22Z No. of bitstreams: 1 Natural Leishmania sp. reservoirs and phlebotomine sandfly food source identification in the Ibitipoca State Park, Minas Gerais, Brazil.pdf: 324232 bytes, checksum: a8c352566ec53e6c15171099e6016e2e (MD5)Made available in DSpace on 2014-06-24T18:32:22Z (GMT). No. of bitstreams: 1 Natural Leishmania sp. reservoirs and phlebotomine sandfly food source identification in the Ibitipoca State Park, Minas Gerais, Brazil.pdf: 324232 bytes, checksum: a8c352566ec53e6c15171099e6016e2e (MD5) Previous issue date: 2012FAPEMIG, CNPq, CPqRR-FIOCRUZFundação Oswaldo Cruz. Centro de Pesquisas René Rachou. Laboratório de Leishmanioses. Belo Horizonte, MG, BrasilFundação Oswaldo Cruz. Centro de Pesquisas René Rachou. Laboratório de Leishmanioses. Belo Horizonte, MG, Brasil/Fundação Oswaldo Cruz. Centro de Pesquisas René Rachou. Centro de Referência Nacional e Internacional para Flebotomíneos. Belo Horizonte, MG, BrasilFundação Oswaldo Cruz. Centro de Pesquisas René Rachou. Laboratório de Leishmanioses. Belo Horizonte, MG, Brasil/Fundação Oswaldo Cruz. Centro de Pesquisas René Rachou. Centro de Referência Nacional e Internacional para Flebotomíneos. Belo Horizonte, MG, BrasilFundação Oswaldo Cruz. Centro de Pesquisas René Rachou. Laboratório de Leishmanioses. Belo Horizonte, MG, Brasil/Fundação Oswaldo Cruz. Centro de Pesquisas René Rachou. Centro de Referência Nacional e Internacional para Flebotomíneos. Belo Horizonte, MG, BrasilLeishmania spp are distributed throughout the world and different species are associated with varying degrees of disease severity. However, leishmaniasis is thought to be confined to areas of the world where its insect vectors, sandflies, are present. Phlebotomine sandflies obtain blood meals from a variety of wild and domestic animals and sometimes from humans. These vectors transmit Leishmania spp, the aetiological agent of leishmaniasis. Identification of sandfly blood meals has generally been performed using serological methods, although a few studies have used molecular procedures in artificially fed insects. In this study, cytochrome b gene (cytB) polymerase chain reaction (PCR) was performed in DNA samples isolated from 38 engorged Psychodopygus lloydi and the expected 359 bp fragment was identified from all of the samples. The amplified product was digested using restriction enzymes and analysed for restriction fragment length polymorphisms (RFLPs). We identified food sources for 23 females; 34.8% yielded a primate-specific banding profile and 26.1% and 39.1% showed banding patterns specific to birds or mixed restriction profiles (rodent/marsupial, human/bird, rodent/marsupial/human), respectively. The food sources of 15 flies could not be identified. Two female P. lloydi were determined to be infected by Leishmania using internal transcribed spacer 1 and heat shock protein 70 kDa PCR-RFLP. The two female sandflies, both of which fed on rodents/marsupials, were further characterised as infected with Leishmania (Viannia) braziliensis. These results constitute an important step towards applying methodologies based on cytB amplification as a tool for identifying the food sources of female sandflies