Development of Lutzomyia evansi immature stages in peridomiciliary environment in a leishmaniasis urban focus in the Colombian Caribbean

ESTRADA, LUIS GREGORIO; ORTEGA, EDGAR; VIVERO, RAFAEL JOSÉ; BEJARANO, EDUAR ELÍAS; CADENA, HORACIO

ACTA TROPICA

ELSEVIER SCIENCE BV

Año: 2020 vol. 208 p. 1 - 9

0001-706X

In the Caribbean region of Colombia, Lutzomyia evansi is recognized as the vector for Leishmania infantum andLeishmania braziliensis. Identifying breeding sites and surveying abundance of immature phlebotomine sand fliesin urban foci of leishmaniasis are useful tool to design new vector control strategies. The objective of this studywas to describe the natural breeding sites of Lu. evansi in peridomiciliary vegetation in a peri-urban area of theColombian Caribbean region. Between 2013 and 2015, 466 microhabitats were sampled, collecting 621 kg of soilsamples. The explored microhabitats were bases and tree holes, fallen trees, animal caves, leaf litter, domesticanimal shelters, and the inside of dwellings. The immature phlebotomines were recovered by direct search underthe stereoscope and incubation of soil samples. In total, 103 microhabitats, associated with 17 arboreal species,were identified as natural breeding sites. Of 422 immature sandflies detected, 98.6% were found in soils at thebase of the trees. Eight species of the genus Lutzomyia were identified, of which Lu. evansi (52.6%) was the mostabundant, followed by Lu. rangeliana, Lu. cayennensis cayennensis, Lu. atroclavata, Lu. micropyga, Lu. trinidadensis,Lu. dubitans and Lu. gomezi. The arboreal species Cordia alba was the most used by phlebotomines for the de-velopment of their immature stages. From 63 natural breeding sites identified 268 immatures were recoveredincluding 176 Lu. evansi. The accumulated precipitation showed correlation (R2= 0.643, p= 0.013) with theabundance of developmental stages, which increased in September and October. The natural breeding sites of Lu.evansi exhibited a local pattern of occurrence dependent on rainfall. The physicochemical analysis of the soilsamples showed that the natural sites for C. alba were categorized as fertile loam soils. This is the first systematicstudy that estimates the temporal variation of immature sand flies in peridomiciliary vegetation in a peri-urbanfocus of leishmaniasis in Colombia.