Shellfish-Associated Viral Disease Outbreaks

Numerous outbreaks of shellfish-borne enteric virus illness have been reported worldwide. Most notable among the outbreaks are those involving norovirus illness and hepatitis A. Lessons learned from outbreak investigations indicate that most outbreaks are preventable. Anthropogenic sources of contamination will continue to invade shellfish growing waters, and shellfish, by their very nature, will continue to bioconcentrate these contaminants, including enteric viruses. There is no quick fix for enteric virus contamination of shellfish; however, vigilance on behalf of the industry, regulatory agencies, and the consumer could substantially reduce the incidence of illness. Enhanced monitoring in all areas of shellfish production, harvesting, distribution, and processing would help to reduce viral illnesses. Pollution abatement and improved hygienic practices on behalf of the industry and consumers are needed. New processing and analytical technologies, such as high hydrostatic pressure processing and molecular biological assays, will enhance shellfish safety and continue to provide new avenues to protect the consumer and the industry. Better reporting and epidemiological follow-up of outbreaks are keys to the development of interventions against the foodborne transmission of viral infections.