Dados do Trabalho

Título

Evaluation the infectivity of dogs to sand flies by xenodiagnoses to determine the role of these animals on maintaining American cutaneous leishmaniasis transmission cycle - PRELIMINARY RESULTS

Introdução

American cutaneous leishmaniasis (ACL), a parasitic disease which affects skin and mucous membranes, is endemic in Brazil, mainly at tropical rain forest region. Pernambuco and its capital, Recife, are endemic for the disease. Definitive reservoirs of disease are wild and synanthropic animals. Dog (Canis familiaris) is the main domestic host of ACL and more data are necessary to understand better the participating of them in the maintenance of transmission cycle. The potential for infectivity of these animals to the vector (sandflies) is a frequent question. Studies have already demonstrated infection of domestic animals by "Leishmania (Viannia) braziliensis". Xenodiagnosis has been the main method to measure transmission potential.

Objetivo(s)

The objective is to evaluate the infectivity of dogs to sandflies and their role in maintaining the ACL transmission cycle in endemic regions.

Material e Métodos

Moreno City, Metropolitan Region of Recife, is endemic for ACL. Blood samples were collected from 5 dogs. A qPCR, using a Sybr Green system, was performed to confirm the presence of L. (V.) braziliensis and quantify the parasite load in dog´s blood. The most infected dog (<100fg of parasite DNA) was chosen to xenodiagnosis.

Resultados e Conclusão

From the sandfly colony of Aggeu Magalhães Institute, were used 25 females and 30 males with five days of blood fasting to xenodiagnosis. With the dog sedated, a sandfly container was attached to its ear, the invertebrates took a blood meal for one hour. All participated sandflies were submitted to qPCR to confirm presence of DNA from L. (V.) braziliensis. Two male sand flies were included on qPCR as negative control. From 25 female (Lutzomyia migonei), one was positive (2.24fg/DNA). Another xenodiagnosis was performed using Lu. evandroi and 25 females were submitted to qPCR. One female was positive to L. (V.) braziliensis (2.12fg/DNA). A study in Brazil found the mean positivity on xenodiagnosis for infectivity of dogs with L. infantum of 10.7% (~80 sandflies/dog). For xenodiagnosis’ of this study, positivity of sandflies was of 4%, with lower number of specimens/dog. To understand the participation of dogs on transmission cycle,more xenodiagnosis must be done, inclusive with different species of sand fly, to contribute on comprehension of how each species is infected by parasite. As so, it could contribute to control recommendations and prevent ACL in endemic areas.

Palavras-chave

American cutaneous leishmaniasis; Xenodiagnosis; Dog; Sand fly; "Leishmania (Viannia) braziliensis".

Área

Eixo 06 | Protozooses