Hemmati Sahel, Afshar Abbas Aghaei, Mohammadi Mohammad Ali, Afgar Ali, Nasibi Saeid, Harandi Majid Fasihi
Research Center for Hydatid Disease in Iran, Kerman University of Medical Sciences, Kerman, 7616914115, Iran.
Dept of Parasitology, School of Medicine, Kerman University of Medical Sciences, Kerman, 7616914115, Iran.
Exp Parasitol. 2018 Jun;189:43-48. doi: 10.1016/j.exppara.2018.04.012. Epub 2018 Apr 19.
Synanthropic fly species can be potential mechanical vectors of many infectious agents. The potential of the flies to carry Echinococcus granulosus eggs is not fully documented. The purpose of the present study was to determine the possible role of non-biting flies to carry taeniid eggs. A total of 210 flies were collected from seven selected sites in areas of Kerman city, southeastern Iran from November 2016 to May 2017. Adult flies were live-caught using sweeping nets. Flies were placed individually in small glass bottles and transported to the laboratory. All the flies were killed by deep freezing and then identified to the species level using both morphological and molecular methods. The flies were homogenized in test tubes and genomic DNA was extracted and amplified by PCR. PCR protocols were used both to identify the live-caught flies to the species level, and for the detection of E. granulosus. The laboratory reared second generation flies were experimentally exposed to dog feces manually spiked by Echinococcus eggs. Two runs of experiments with 1-3 h of exposure were designed. For each experiment 20 flies were selected from the stock colony and were starved for three days. After each experiment, the flies were frozen for further molecular studies. The dominant fly species were Musca domestica and Lucilia sericata. No eggs were found on the body surface and/or guts of live-caught flies. After the first hour of exposure, 60%, of the flies of both species were found to harbor Echinococcus eggs. However, in the case of L. sericata 50% of the flies harbored Echinococcus eggs after 3 h of exposure. Results of the present study indicate the probable role of synanthropic flies in harboring Echinococcus eggs and mechanical transmission of cystic echinococcosis. When the helminth eggs are susceptible to desiccation grooming flies can remove many of eggs from exterior surfaces of them. Despite this result the role of synanthropic flies in the transmission of certain helminthiases should not be discounted because of their vagility and feeding mechanisms.
共栖蝇类可能是多种感染因子的潜在机械传播媒介。苍蝇携带细粒棘球绦虫卵的可能性尚未得到充分记录。本研究的目的是确定非吸血蝇类携带带绦虫卵的可能作用。2016年11月至2017年5月，从伊朗东南部克尔曼市地区的七个选定地点共收集了210只苍蝇。成年苍蝇用捕虫网活捉。苍蝇被单独放入小玻璃瓶中并运到实验室。所有苍蝇通过深度冷冻处死，然后使用形态学和分子方法鉴定到物种水平。将苍蝇在试管中匀浆，提取基因组DNA并通过PCR扩增。PCR方案既用于将活捉的苍蝇鉴定到物种水平，也用于检测细粒棘球绦虫。将实验室饲养的第二代苍蝇实验性地暴露于人工添加细粒棘球绦虫卵的狗粪便中。设计了两组暴露1 - 3小时的实验。每次实验从种群中挑选20只苍蝇并使其饥饿三天。每次实验后，将苍蝇冷冻以便进一步进行分子研究。优势蝇种为家蝇和丝光绿蝇。在活捉的苍蝇体表和/或肠道中未发现虫卵。暴露1小时后，发现这两种苍蝇中有60%携带细粒棘球绦虫卵。然而，对于丝光绿蝇，暴露3小时后有50%的苍蝇携带细粒棘球绦虫卵。本研究结果表明共栖蝇类在携带细粒棘球绦虫卵和囊型包虫病的机械传播中可能发挥作用。当蠕虫卵易受干燥影响时，梳理毛发的苍蝇可以从其外表面清除许多虫卵。尽管有此结果，但由于共栖蝇类的移动性和取食机制，它们在某些蠕虫病传播中的作用不应被忽视。
