Faisal Mohamed, Schulz Carolyn A
Department of Fisheries and Wildlife, Michigan State University, S-112 Plant Biology Building, East Lansing, MI, 48824, USA.
Parasit Vectors. 2009 Sep 28;2(1):45. doi: 10.1186/1756-3305-2-45.
The leech Myzobdella lugubris is widespread in the Lake Erie Watershed, especially Lake St. Clair. However, its role in pathogen transmission is not fully understood. In this same watershed, several widespread fish mortalities associated with the Viral Hemorrhagic Septicemia virus (VHSV) were recorded. Viral Hemorrhagic Septicemia is an emerging disease in the Great Lakes Basin that is deadly to the fish population, yet little is known about its mode of transmission. To assess the potential role of M. lugubris in VHSV transmission, leeches were collected from Lake St. Clair and Lake Erie and pooled into samples of five. Cell culture and reverse transcriptase polymerase chain reaction (RT-PCR) were used to determine the presence of the virus and its identity. Results showed that 57 of the 91 pooled leech samples were positive by cell culture for VHSV and 66 of the 91 pooled leech samples were positive by RT-PCR for the VHSV. Two representative virus isolates were sequenced for further genetic confirmation and genotype classification. VHSV detected within M. lugubris was homologous to the Great Lakes strain of VHSV genotype IVb. This is the first record of the VHSV being detected from within a leech, specifically M. lugubris, and suggests the potential of M. lugubris being involved in VHSV transmission.
蚂蟥Myzobdella lugubris广泛分布于伊利湖流域，尤其是圣克莱尔湖。然而，其在病原体传播中的作用尚未完全明确。在同一流域，记录到几起与病毒性出血性败血症病毒（VHSV）相关的广泛鱼类死亡事件。病毒性出血性败血症是五大湖流域的一种新出现疾病，对鱼类种群具有致命性，但对其传播方式知之甚少。为评估Myzobdella lugubris在VHSV传播中的潜在作用，从圣克莱尔湖和伊利湖采集蚂蟥并每五只分为一组。采用细胞培养和逆转录聚合酶链反应（RT-PCR）来确定病毒的存在及其身份。结果显示，91组蚂蟥样本中有57组通过细胞培养检测出VHSV呈阳性，91组蚂蟥样本中有66组通过RT-PCR检测出VHSV呈阳性。对两个代表性病毒分离株进行测序以作进一步的基因确认和基因型分类。在Myzobdella lugubris体内检测到的VHSV与VHSV基因型IVb的五大湖毒株同源。这是首次从蚂蟥（具体为Myzobdella lugubris）体内检测到VHSV，并表明Myzobdella lugubris可能参与VHSV传播。
