Dados do Trabalho

Título

Sand flies’ diversity, temporal distribution and natural infection with Leishmania spp in an endemic area of cutaneous leishmaniasis of Caldas Department-Colombia

Introdução

The Phlebotomine Sand flies group include species recognized as vectors of Leishmania spp. The sand fly species diversity in Colombia is high, 172 species, 14 of them are suspected or proven vectors of Leishmania spp. The municipality of Victoria (Caldas, Colombia) is endemic for cutaneous leishmaniasis, where cases have been reported each year, mainly in the rural area. Studies on species diversity and their distribution provide key elements to understand the epidemiology of leishmaniasis by identifying populations of vectors as well the vector-parasite interactions in endemic areas.

Objetivo(s)

This study aimed to describe the monthly distribution of the sand fly fauna, the species diversity and to evaluate the circulation of Leishmania spp in an endemic area of cutaneous leishmaniasis.

Material e Métodos

Sampling of sand flies was carried out monthly from September to February (2020) and November to October (2021) with CDC-type light traps installed, both, in the intra and peridomicile of six houses. Additionally, a Shannon trap was installed in a peridomicile. A sample of females had their head and terminal part of the abdomen separated from the rest of the body for species identification, based on the characters of the head and of the spermathecae. After that, DNA was extracted from the remaining parts of the body. To investigate the presence of Leishmania sp DNA, female sandflies were grouped into pools according to species. The presence of Leishmania was identified by conventional PCR using HSP70 gene as the target.

Resultados e Conclusão

8,223 phlebotomine sand flies were collected. The specimens belongs to 23 species distributed in 13 genera. Nyssomyia yuilli yuilli, Psychodopygus ayrozai and Ps. panamensis, predominated throughout the period. In CDC traps a total of 6,067 females and 1,932 males were collected. Females were more frequent in all collection sites (female/male ratio: 3:1). A total of 836 females of 15 species were grouped in 327 pools and processed. Leishmania sp was detected in four pools giving a minimum infection rate of 1.2%. The positive pools belongs to the species Ny. yuilli yuilli and Ps. ayrozai. In the epidemiological context, the circulation of infected sand flies, the capture in intradomicile of antrophophilic species and their presence during all year, suggest a constant exposition of the human population to vector and parasites what could lead to increase odds of leishmaniasis cases occurrence.

Palavras-chave

sand fly, leishmaniasis, natural infection.