Identification and observational epidemiological study of flebotominic fauna (diptera: psychodidae: phlebotominae) in the transmission area of canine visceral leishmaniasis in the municipality of Lavras, Minas Gerais, Brazil

Abstract

Leishmaniasis is a complex of infectious parasitic diseases, of zoonotic nature and caused by vector transmission of different species of the genus Leishmania. The infection is caused by the protozoan Leishmania infantum, transmitted by dipterans known as phlebotomines. Despite the wide geographical distribution of this parasite, several regions of Brazil are still considered free of Leishmaniasis. Although exist vast literature about this disease, many ecoepidemiological aspects of insect vectors are still remain unknown.Thus, the objective of this study was to know the epidemiological situation and investigate the phlebotominal fauna in a region of recent transmission of visceral and tegumentary leishmaniasis in the municipality of Lavras, located on the southern state of Minas Gerais, Brazil. The canine serological study was carried out in partnership with the Environmental Surveillance and consisted in the evaluation of 6 090 residences and the test of 6 782 animals using the TR DPP and the EIE. Monthly systematic collections were performed using traps HP-type and convenience collections using Shannon and HP luminous traps at sites where was reported cases of LV in human and canine, from June 2013 to 2018. As a result, a total of 759 animals were positive in the screening tests, using the protocol recommended by the Ministry of Health. Of these, 443 animals were positive in the rapid test and EIE, where the majority of cases occurred in the following neighborhoods: Jardim Glória, Jardim Alterosa and Joaquim Sales. Regarding the vectors, 136 sandflies belonging to 16 different species were captured. The most abundant species was Lutzomyia longipalpis (43%) followed by Evandromyia cortelezzii (9%), Pyntomyia monticola (8%) and Migonemyia migonei (7%). No significant correlation between rainfall or temperature and abundance of sand flies were observed.In conclusion, due to high occurrence of canine infection by L. infantum, human cases and high diversity of sandflies in that area, is necessary surveillance measures and control in order to avoid the spread of the disease. It is also important carry out studies to better understand the epidemiological determinants associated with leishmaniasis in the city of Lavras, Minas Gerais, Brazil.