Following reports of norovirus-like illnesses in people who report eating raw oysters from several areas in Washington and elsewhere, public health officials at the Washington State Department of Health have tracked down areas where some of the illness-linked oysters were harvested. Over the past several weeks, small harvest closures and recalls have been ordered, the largest of which is in Hammersley Inlet in Mason County, where a recall has been issued for any shellfish harvested there since March 15. Smaller portions of the shellfish harvesting area were closed and shellfish recalled on March 2, April 4 and April 5.
The three-mile stretch of commercial shellfish growing beds is about two-thirds of the Hammersley Inlet growing area and is harvested by 31 shellfish companies. Shellfish harvested from the area is typically shipped to many states and countries. Shellfish growers and the Department of Health are working with local health jurisdictions and other states to track down all harvested product to make sure it is not available to be consumed.
“We are actively evaluating all potential pollution sources in the area to determine what is causing the contamination. The area will remain closed until we can assure that public health is protected,” said Rick Porso, Director of the Office of Environmental Health and Safety. “This issue underscores the importance of protecting our marine water, especially in areas where shellfish are grown.”
Norovirus is a common stomach virus that spreads easily. It can be transmitted through contaminated food or surfaces and person-to-person contact. The source of norovirus is people — specifically, the feces and vomit of infected individuals. The virus can be present in marine water indirectly through boat discharges, failing septic systems, malfunctioning wastewater treatment plants, or directly from an infected person. Because shellfish are filter feeders, they can concentrate the virus and infect people who eat them raw or undercooked.
Norovirus symptoms include watery diarrhea, vomiting and stomach pain. Most people get better within two days. Dehydration can be a problem among some people, especially the very young, the elderly, and people with other illnesses. For those consumers concerned about the increased risk of illness, ordering and eating cooked shellfish is an effective way to prevent norovirus illness.
The Department of Health is responsible for the safety of commercial shellfish harvested in the state. The agency’s Office of Environmental Health and Safety uses national standards to classify all commercial shellfish harvesting areas. People who gather their own shellfish should always check the Shellfish Safety Map to learn about closures or health warnings.