Gomez Eduardo A, Kato Hirotomo, Mimori Tatsuyuki, Hashiguchi Yoshihisa
Departamento de Medicina Tropical, Facultad de Medicina, Universidad Catolica de Guayaquil, Ecuador.
Laboratory of Parasitology, Department of Disease Control, Graduate School of Veterinary Medicine, Hokkaido University, Japan.
Acta Trop. 2014 Sep;137:118-22. doi: 10.1016/j.actatropica.2014.05.006. Epub 2014 May 22.
Distribution of the vector species is a major risk factor for the endemicity of leishmaniasis. In the present study, the vertical distribution of Lutzomyia (Lu.) ayacuchensis, the vector of Leishmania (Leishmania) mexicana in the Ecuadorian Andes, was surveyed at different altitudes (300-2500m above sea level) of the Andean slope. The vector species Lu. ayacuchensis was identified at an altitude of 650m and a higher areas, and higher distribution ratio of the species was observed at higher altitudes. In addition, high ratios of L. (L.) mexicana infection were detected in higher areas, but none in lower populations of sand flies. Since an association between sand fly populations and vector competence is suggested in Lu. ayacuchensis, haplotype analysis was performed on the species from different altitudes of the study areas; however, no apparent difference was observed among populations. These results suggested that Lu. ayacuchensis in Andean slope areas of Ecuador has the potential to transmit L. (L.) mexicana and spread leishmaniasis in these areas.
媒介物种的分布是利什曼病流行的一个主要风险因素。在本研究中，对厄瓜多尔安第斯山脉中利什曼原虫（墨西哥利什曼原虫）的媒介阿亚库乔罗蛉（Lutzomyia (Lu.) ayacuchensis）在安第斯山坡不同海拔（海拔300 - 2500米）的垂直分布进行了调查。在海拔650米及更高区域鉴定出了媒介物种阿亚库乔罗蛉，且在较高海拔处观察到该物种的分布比例更高。此外，在较高区域检测到较高比例的墨西哥利什曼原虫感染，但在较低海拔的沙蝇种群中未检测到感染。由于阿亚库乔罗蛉存在沙蝇种群与媒介能力之间的关联，因此对研究区域不同海拔的该物种进行了单倍型分析；然而，各种群之间未观察到明显差异。这些结果表明，厄瓜多尔安第斯山坡地区的阿亚库乔罗蛉有传播墨西哥利什曼原虫并在这些地区传播利什曼病的潜力。
