Environmental factors associated with American cutaneous leishmaniasis in a new Andean focus in Colombia

Abstract

OBJECTIVE To evaluate the environmental and ecological factors associated with Leishmania transmission and vector abundance in Chaparral, Tolima-Colombia. METHODS First, we compared the ecological characteristics, abundance of phlebotomies and potential reservoir hosts in the peridomestic environment (100 m radius) of randomly selected houses, between two townships with high and low cutaneous leishmaniasis incidence. Second, we examined peridomestic correlates of phlebotomine abundance in all 43 houses in the higher risk township. RESULTS The high transmission township had higher coverage of forest (23% vs. 8.4%) and shade coffee (30.7% vs. 11%), and less coffee monoculture (16.8% vs. 26.2%) and pasture (6.3% vs. 12.3%), compared to the low transmission township. Lutzomyia were more abundant in the high transmission township 2.5 vs. 0.2/trap/night. Lutzomyia longiflocosa was the most common species in both townships: 1021/1450 (70%) and 39/80 (49%). Numbers of potential wild mammal reservoirs were small, although four species were found to be infected with Leishmania (Viannia) spp. In the high transmission township, the overall peridomiciliary capture rate of L. longiflocosa was 1.5/trap/night, and the abundance was higher in houses located nearer to forest (ρ = −0.30, P = 0.05). CONCLUSION The findings are consistent with a domestic transmission cycle with the phlebotomies dependent on dense vegetation near the house.

Ocorrência de casos de leishmaniose tegumentar americana: uma análise multivariada dos circuitos espaciais de produção, Minas Gerais, Brasil, 2007 a 2011

“…Esse resultado mostra o caráter ocupacional da doença nesses territórios, a relação em que o ambiente silvestre alterado pelas práticas agrícolas em áreas rurais pode determinar a ocorrência de casos. Nossos resultados são consistentes com os encontrados em trabalhos anteriores, que também identificaram o ambiente rural 8,12 e áreas de floresta favoráveis para focos de LTA 7,8,20,21 .…”

“…ção de diferentes sistemas agropecuários reforça mais uma vez o caráter ocupacional, e como as ações do homem sobre a terra podem afetar a qualidade da paisagem e consequentemente afetar a composição da fauna flebotomínica, podendo ser determinantes na transmissão da LTA nessas regiões 7,20,21 .…”

Risk Factors Associated With American Cutaneous Leishmaniasis in an Endemic Area of Brazil

“…According to Ocampo et al 17 ,. in a study in Colombia, ACL transmission by sandflies depends on the presence of dense vegetation near the houses.…”

Species Typing in Dermal Leishmaniasis

“…The assay was tested on a large panel of strains and could differentiate them to the complex level, but L. aethiopica was not evaluated (Table 1). Both methods have been used on environmental and clinical samples (212)(213)(214).…”