Khogali Altayeb, Elnaiem Dia-Eldin A, Díaz-Regañón Ramón, Jibreel Tayseer, Nour Bakri Y M, Abdelrahman Samira Hamid, Molina Ricardo, Jiménez Maribel
Blue Nile National Institute for Communicable Diseases, University of Gezira, Wad Medani 21111, Sudan.
Department of Natural Sciences, University of Maryland Eastern Shore, 1 Backbone Rd., Princess Anne, MD 21853, USA.
Trop Med Infect Dis. 2024 Feb 2;9(2):40. doi: 10.3390/tropicalmed9020040.
A study was carried out to compare the infection rates of in sandflies at different microhabitats of a VL endemic village in Gedarif state, Sudan. DNA extracts of 1078 sand fly females sampled by CDC light traps from indoor, outdoor, peri-domestic, and sylvatic sites, in three transmission seasons, March-June 2016-18, in Helat-Belo village, were subjected to independent PCR amplifications targeting kDNA and the gene followed by ITS1 region sequencing. kDNA was detected in 1.4% of the 1078 females captured in the area. Two of these specimens showed a characteristic 741 bp band of after gene amplification. The DNA sequence of the ITS1 region of the parasites matched the ITS1 genotype F. There were no signficant differences between rates of infection of in captured at different sites. Blood meals found in infected flies origninated from human (5 specimens), cattle (4 specimens) and donkey (2 specimens). The finding of fresh cow and donkey blood in the infected flies suggests the possible role of these animals in the zoopotentiation and/or zooprophylaxis against VL. The study provides important information for VL transmission models and control programs in East Africa.
在苏丹加达里夫州一个内脏利什曼病（VL）流行村庄的不同微生境中，开展了一项研究以比较白蛉体内利什曼原虫的感染率。在2016 - 18年3月至6月的三个传播季节里，从赫拉特 - 贝洛村的室内、室外、居家周边和森林地区，用疾控中心（CDC）诱虫灯捕获了1078只雌性白蛉，并提取其DNA，对其进行针对利什曼原虫动基体DNA（kDNA）和小亚基核糖体RNA（SSU rRNA）基因的独立聚合酶链反应（PCR）扩增，随后对内部转录间隔区1（ITS1）区域进行测序。在该地区捕获的1078只雌性白蛉中，1.4%检测到了利什曼原虫kDNA。其中两个样本在SSU rRNA基因扩增后显示出利什曼原虫特征性的741碱基对条带。寄生虫ITS1区域的DNA序列与ITS1基因型F匹配。在不同地点捕获的白蛉中，利什曼原虫的感染率没有显著差异。在感染的白蛉中发现的血餐来源包括人类（5个样本）、牛（4个样本）和驴（2个样本）。在感染的白蛉中发现新鲜的牛血和驴血，表明这些动物在VL的动物增强作用和/或动物预防作用中可能发挥的作用。该研究为东非的VL传播模型和控制计划提供了重要信息。
