Parasitology Department, Medical Research Institute, Alexandria University, 165 El-Horreya Avenue, El-Hadara, Alexandria 21561, Egypt.
Vet Parasitol. 2010 Dec 15;174(3-4):234-40. doi: 10.1016/j.vetpar.2010.08.027. Epub 2010 Sep 28.
Paramphistomiasis is a disease of domestic and wild ruminants caused by some digenetic trematodes of the superfamily Paramphistomoidea. Human infections with certain species of paramphistomes have been reported. Given their ubiquity and their abundance within hosts, it seems likely that the importance of these worms is underestimated globally. Based on the reported difficulties of morphological identification of paramphistomes, the development of alternative approaches to better delineate species is needed. Paramphistome samples examined during this study were cercariae, rediae from snail hosts and adult flukes obtained from slaughterhouses from Kenya, Tanzania, Egypt and Nepal. The results confirm that ITS2 is a good molecular marker for paramphistome identification and can be used to determine the affiliation of samples among the different taxa of Paramphistomoidea. Our 22 samples include eight species of paramphistomes. Ten samples of paramphistome larvae (cercariae or rediae) yielded seven species and the 12 samples of adult flukes from bovines yielded four, only one of which was not also represented among the larvae. We found three cases in which the sequences for adult worms and larvae matched, thus revealing the hosts involved locally in those particular life cycles. We interpret our specimens to include five species from Kenya, two from Nepal, two from Tanzania and one from Egypt. Bulinus forskalii was found infected with three species of paramphistomes. The results of the present study will help construct a framework to facilitate identification and eventually control of this underestimated cosmopolitan group of digeneans.
片形吸虫病是一种由片形科吸虫引起的家畜和野生动物疾病。已报告人类感染某些片形吸虫。鉴于这些吸虫的普遍存在及其在宿主中的丰富度，全球范围内这些蠕虫的重要性可能被低估了。基于报告的片形吸虫形态学鉴定困难，需要开发替代方法来更好地区分物种。本研究检查的片形吸虫样本包括从肯尼亚、坦桑尼亚、埃及和尼泊尔屠宰场获得的尾蚴、来自蜗牛宿主的雷蚴和成虫。结果证实 ITS2 是鉴定片形吸虫的良好分子标记，可以用于确定不同片形科分类群之间样本的归属。我们的 22 个样本包括 8 种片形吸虫。10 个片形吸虫幼虫（尾蚴或雷蚴）样本产生了 7 种，12 个来自牛的成虫样本产生了 4 种，其中只有 1 种未在幼虫中出现。我们发现了 3 种成虫和幼虫序列匹配的情况，从而揭示了当地参与这些特定生命周期的宿主。我们将我们的标本解释为包括来自肯尼亚的 5 种、来自尼泊尔的 2 种、来自坦桑尼亚的 2 种和来自埃及的 1 种。多房棘口吸虫感染了 3 种片形吸虫。本研究的结果将有助于构建一个框架，以促进对这个被低估的世界性双腔吸虫群体的鉴定和最终控制。
