Freshwater Mussels as Biological Indicators

Viral hemorrhagic septicemia virus (VHSV) is a devastating rhabdovirus affecting freshwater fishes worldwide. In 2005, a new genotype of VHSV (IVb) was discovered in Lake St. Clair and has consequently spread throughout the Laurentian Great Lakes. While it is widely known that freshwater fishes are hosts and transmitters of VHSV, little is known about the ability of invertebrates to take up and carry the virus. Our (Vera Kazaniwskyj, Y. Zhang, G. Thomas Watters, Dr. Kody Kuehnl, and Barbara Wolfe) objective in this study was to investigate the ability of freshwater mussels to accumulate and transmit VHSV by using two commonly occurring freshwater mussel species (Corbicula fluminea and Amblema plicata) and to assess the efficacy of freshwater mussels as bioindicators of viral presence. Experiments used inoculations of 100 and 200 Tissue Culture Infective Dose units of VHSV. Mussel tissues were tested for VHS at 72h, 120h, and 168h post-exposure using rt-PCR. Initial results indicate that freshwater mussels have the ability to harbor the VHS virus, especially when inoculated with high doses, and thus can serve as valuable indicators of viral presence. These results also indicate mussels are not likely to maintain VHS long term within their tissues, and are therefore not likely vectors of the disease.https://fuse.franklin.edu/forum-2013/1021/thumbnail.jp