Norovirus outbreak linked to oysters; health officials order recall and harvest area closure

The Louisiana Department of Health has closed a molluscan shellfish harvesting area in Area 3 and ordered a recall of all oysters harvested from that area since Jan. 10 because of an outbreak of norovirus-like illnesses. 

The recall includes frozen, shucked, breaded, post-harvest processed and oysters for the half-shell market.

Area 3 is located east of Lake Borgne, north of Eloi Bay, and includes Chandeleur Islands and surrounding marshes. 

Fifteen people became ill with norovirus-like illness after eating the Louisiana oysters harvested from Area 3 at several New Orleans restaurants between Jan. 15 and Jan. 31. The illnesses were not life-threatening, but two people were hospitalized and have been discharged.

Cooking kills the virus, but other outbreaks have occurred from eating undercooked oysters harvested from contaminated waters.

The health department is coordinating with the Louisiana Department of Wildlife and Fisheries to ensure no oysters are harvested from these waters during the closure. Louisiana Surgeon General Ralph Abraham, M.D., and LDH Secretary Michael Harrington signed the closure order which took effect Feb. 4. The Area 3 harvesting area is expected to be closed for at least 21 days. 

The health department has notified local oyster harvesters who work in the affected area and the Louisiana Oyster Task Force.

The department is continuing its health investigations and environmental monitoring of the closed oyster waters and will reopen them as soon as they meet Interstate Shellfish Sanitation Conference (ISSC) standards. This determination is made by staff with the Office of Public Health’s Molluscan Shellfish Program. Oyster waters are cleaned by the natural cycle of tides. 

Oysters are filter feeders and can accumulate contaminants and microorganisms present in the water, which can in turn affect people who eat raw or under-processed contaminated oysters.

If you suspect you have become ill from contaminated oysters, please contact your regional epidemiologist or submit a report here.

Food contaminated with norovirus does not look, smell or taste bad. Anyone who has eaten oysters and developed symptoms of norovirus infection should contact their doctor.

Symptoms may include severe vomiting and/or severe diarrhea, nausea, muscle aches, fever, and headache. Symptoms typically start 12 to 48 hours after exposure and can last for one to three days. Most people recover without treatment, however some may need medical attention for dehydration.

People with norovirus infections can spread the infection easily to others. The virus can live on surfaces for long periods of time.

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