Feeling Seasick?

Courtesy of Alvin Smith This cluster of six Vesiviruses, using negative stain electron microscopy, shows their typical shape.

The results showed an interesting correlation with liver damage. Among normal blood donations, 12% had antibodies to the virus but in donors with liver damage, 21% had antibodies. Based on this preliminary data, the researchers obtained blood samples from patients with clinical hepatitis, or inflammation of the liver, and found that 29% of those samples had antibodies. Finally, in people who developed hepatitis from an unknown cause after being transfused - 47% had antibodies to Vesivirus.

Further testing that looked for the presence of the actual virus also showed a higher proportion of infections among people with liver damage. Eleven percent of people with liver damage had the virus, compared to only 5% for normal blood donors.

Although this study doesn't prove that Vesivirus infection causes hepatitis in humans, Smith says that there is no reason to believe that it doesn't. He is currently working on strengthening the evidence of a link between Vesivirus and hepatitis so he can push for Vesivirus screening of the blood supply.

Environmental exposure may put some people at risk of contracting Vesivirus, and it is always wise to keep a safe distance from sickly-looking animals, but researchers believe the biggest danger is probably contaminated meat, seafood, or drinking water. Smith advises against eating undercooked or raw seafood.

For those who are infected, biotech company AVI BioPharma is investigating the use of their proprietary NeuGene antisense compound as an anti-viral treatment for Vesivirus. The technology uses a synthetic compound that binds closely with points along the code of the RNA sequence that tell the virus to begin replication. "It's like blocking a zipper," says Smith.

NeuGene drugs developed using this technology successfully stopped an outbreak of fatal Calicivirus in cats. The company is developing several other drug candidates for treatment of other RNA viruses including hepatitis C, influenza, and West Nile virus. This technology may signal the beginning of the end of the "wait and see" approach to viral infection treatment.

For more information:

MedScape - Marine Virus May Account for Some Unexplained Human Illnesses
http://www.medscape.com/viewarticle/533457

Eastern Virginia Medical School - Virus linked to hepatitis may have ocean origin
http://www.evms.edu/about/news/2006-03-27-matson-hepatitis.html