The U.S. Food and Drug Administration has expanded its warning to restaurants, retailers and consumers not to serve, sell or eat certain frozen half-shell oysters from South Korea’s Designated Area II, linked to a norovirus outbreak in California.

The updat follows an expanded recall by Daihung Mulsan Co., Ltd. (KR 7 SP) of the Republic of Korea, adding harvest dates Jan. 31, Feb. 1, and Feb. 2, 2024, to the initial recall covering Jan. 30 and Feb. 4, 2024.

Sea Win, Inc. of Los Angeles, CA, the U.S. importer, first recalled 650 cases of the oysters on March 7 after the California Department of Public Health tied them to multiple illnesses. The latest updat broadens the scope as the FDA and state officials continue investigating. The oysters, processed by KR 7 SP and shipped to Sea Win, were distributed to wholesalers in Los Angeles and Irvine, CA, and possibly other states.

Norovirus, a highly contagious virus, triggers symptoms like diarrhea, vomiting, nausea, and stomach cramps within 12 to 48 hours of exposure, typically lasting one to three days. The FDA cautions that severe illness is possible, especially for those with weakened immune systems. No official case count has been released.

Recalled product:

Sea Win — Frozen Half Shell Oysters Labeled KR 7 SP and packed in white corrugated boxes with 144-count shellfish tags. 

• The updated recall now includes these harvest dates: Jan. 30, Jan. 31, Feb. 1, Feb. 2 and Feb. 4, 2024. 

The FDA advises restaurants and retailers to dispose of the oysters or arrange destruction through distributors and warns consumers against eating them. Those experiencing symptoms should seek medical care. 

Restaurants and retailers are also advised to wash hands thoroughly and sanitize surfaces that may have contacted the oysters.

The agency is monitoring distribution and working with California authorities, promising further updates as new details emerge. Consumers can report issues to the FDA’s Human Food Program, and Sea Win is offering refunds for returned product.