Caron Y, Lasri S, Losson B
Department of Infectious and Parasitic Diseases, Faculty of Veterinary Medicine, University of Liège, B-4000 Liège, Belgium.
Vet Parasitol. 2007 Oct 21;149(1-2):95-103. doi: 10.1016/j.vetpar.2007.07.012. Epub 2007 Aug 13.
A previous study conducted in Belgium revealed that genetic material of Fasciola sp. was present in snail species belonging to the genus Radix. Here, these snails were collected and identified by DNA-based techniques as Radix labiata and Radix balthica. These two species and Galba truncatula (the major intermediate host in Europe) were experimentally infected with Fasciola hepatica. The resulting metacercariae were fed to rats and the infection was monitored using several techniques. Microscopy revealed the presence of larval stages in 78.3, 45, and 6.25% of G. truncatula, R. labiata, and R. balthica snails, respectively. These results were confirmed by a PCR that amplifies a Fasciola sp. specific sequence. Furthermore, this PCR was found to be more sensitive than microscopic examination. R. labiata shed fewer metacercariae than G. truncatula but these were as infective to rats as those shed by G. truncatula. This study demonstrates that R. labiata may act as an incidental intermediate host for F. hepatica in Belgium.
此前在比利时进行的一项研究表明，椎实螺属的蜗牛体内存在片形吸虫属的遗传物质。在此，这些蜗牛通过基于DNA的技术被收集并鉴定为唇形椎实螺和 Baltic椎实螺。这两个物种以及截口土蜗（欧洲主要的中间宿主）被用肝片吸虫进行实验性感染。将由此产生的尾蚴喂给大鼠，并使用多种技术监测感染情况。显微镜检查显示，截口土蜗、唇形椎实螺和 Baltic椎实螺中分别有78.3%、45%和6.25%的蜗牛体内存在幼虫阶段。这些结果通过扩增片形吸虫属特定序列的PCR得到了证实。此外，发现这种PCR比显微镜检查更敏感。唇形椎实螺排出的尾蚴比截口土蜗少，但对大鼠的感染性与截口土蜗排出的尾蚴相同。这项研究表明，唇形椎实螺在比利时可能作为肝片吸虫的偶然中间宿主。
