Phlebotomine sand flies associated with a Boa constrictor snake in a chicken coop: species identification, trypanosomatid infection, and control

Abstract

Phlebotomine sand flies are known vectors of Leishmania spp. to mammals, but also may transmit Sauroleishmania, and Trypanosoma spp. to reptiles and amphibians. In the Brazilian Cerrado, the interactions among snakes, sand flies, and trypanosomatids remain poorly understood. Here, we describe sand flies associated with a Boa constrictor snake in a chicken coop and investigate trypanosomatid infections within these insects. In 2023, we observed sand flies resting on the snake and collected them using a manual aspirator. After seven days, we carried out collections using HP light traps over three consecutive nights. We counted the sand flies and grouped the female specimens into pools to detect trypanosomatids using SSU rRNA PCR. The snake was removed, and environmental management measures were implemented in the coop, including thorough cleaning and the installation of a cement floor. We conducted a subsequent collection for two nights in 2024. We collected a total of 1220 sand flies. We chose 230 females to test for trypanosomatids and used the rest (990) to identify the species. We identified 70 Evandromyia lenti (68 males and two engorged females) and four male Ev. evandroi resting on the snake. Inside the chicken coop, we collected 912 specimens (862 males and seven females of Ev. lenti, 40 males of Ev. evandroi, and three males of Ev. termitophila). Only one male Ev. lenti was captured in the nearby house. PCR revealed trypanosomatid DNA in four female pools (17 %), and no Leishmania DNA was detected. After environmental intervention, only three sand flies were captured. Ev. lenti was the most frequent species in the chicken coop interacting with the snake. Females collected in the coop were infected with trypanosomatids, and environmental management substantially reduced the local abundance of sand flies within two weeks.