Experimental and field investigation of non-biting flies as potential mechanical vectors of Echinococcus granulosus eggs

• Published in: Experimental parasitology 2018-06, Vol.189, p.43-48
• Main Authors: Hemmati, Sahel, Afshar, Abbas Aghaei, Mohammadi, Mohammad Ali, Afgar, Ali, Nasibi, Saeid, Harandi, Majid Fasihi
• Format: Article
• Language: English
• Subjects: Echinococcosis; Lucilia; Musca; Taeniidae; Transmission
• ISSN: 0014-4894; 1090-2449
• DOI: 10.1016/j.exppara.2018.04.012

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. [Display omitted] •The potential of synanthropic flies for harboring E. granulosus eggs was investigated.•After experimental exposure to spiked dog feces, half of the flies harbored E. granulosus eggs.•No eggs were found on the body surface and/or guts of live-caught flies in the field.•The study indicates the probable role of flies in mechanical transmission of CE.