masterThesis
Sazonalidade na exposição a flebotomíneos em cães e humanos em área endêmica para leishmaniose visceral: um estudo de intervenção
Fecha
2016-09-19Registro en:
MORAIS, Ingryd Câmara. Sazonalidade na exposição a flebotomíneos em cães e humanos em área endêmica para leishmaniose visceral: um estudo de intervenção. 2016. 55f. Dissertação (Mestrado em Bioquímica) - Centro de Biociências, Universidade Federal do Rio Grande do Norte, Natal, 2016.
Autor
Morais, Ingryd Câmara
Resumen
Visceral leishmaniasis in Brazil is caused by the protozoan Leishmania infantum. The main vector for L. infantum transmission is Lutzomyia longipalpis and domestic dogs are considered the main reservoir of this protozoan. The major control’s measure of this disease in Brazil is the euthanasia of infected dogs. However, this measure has not been effective due to several factors, including the time lag of implementation after human infection. The use of deltamethrin-impregnated dog collars has been one of the potential alternative measures of infection control. This strategy seems to reduce the risk of exposure of these animals to phlebotomines, with consequent decrease in canine exposure. The aim of this work was to determine the rate of exposure of humans and dogs to the vectors after adoption of deltamethrin impregnated collars by dogs resident in an endemic area for visceral leishmaniasis in Natal, RN, Brazil. A case-control study was designed, in which in the intervention area dogs received collars impregnated with deltamethrin, in addition to traditional control measures; while in the control area only euthanasia was performed. Dogs and people from both areas had blood samples collected, one collection for humans and three for dogs (intervention time, 6 months and one year after). In order to determine the levels of vector exposure, anti-salivary antibodies were obtained by ELISA using salivary gland homogenate of L. longipalpis (for humans and dogs) and recombinant proteins LJM11 / LJM17 (for humans). It was verified that in the control area there was a difference between the levels of antibodies of the three canine collections (p <0.0001), whereas in the intervention area, no difference was observed in the antibody levels of the three collections (p=0.15). In the intervention area, humans showed lower titers of anti-SGH antibodies (p <0.0001), anti-LJM11/17 (p=0.0002) and anti-Leishmania (p<0.0001) when compared to individuals in the control area. Men and women were equally exposed to the vector, regardless of the study area. Salivary gland anti-homogenate antibody levels correlated with recombinant protein antibody levels in humans (r=0.56). This work demonstrates the need to investigate the efficacy of new leishmaniasis control measures, taking into account the biological cycle of the parasite, the seasonal aspect of density and vector exposure, as well as the specific environmental conditions of each locality.