U.S. federal regulators are urging food handlers to remove South Korean oysters, clams, mussels and scallops from the market because the shellfish may have been exposed to human waste.
The Food and Drug Administration said Thursday the affected products could be contaminated with norovirus, which causes nausea, cramps, diarrhea and fever.
The recall includes fresh and canned South Korean shellfish that entered the United States before May 1. The FDA says not all U.S. food companies have heeded initial notification given last month about the contaminated seafood.
The FDA says the Korean Shellfish Sanitation Program no longer meets the sanitary controls specified by U.S. regulators, including control of pollution in shellfish growing areas.