Norovirus is a foodborne pathogen that can cause acute gastroenteritis in humans.
The federal and state officials said they are notifying consumers, food service operators and retailers nationwide about the outbreak associated with oysters recently harvested from an area near Port Sulphur, La., known as Area 7. The oysters were sold or distributed nationwide.
The FDA is warning consumers not to purchase or eat oysters from the affected area and warning retailers and food-service operators not to sell or serve them. Louisiana's Area 7 is in the Gulf of Mexico, near the mouth of the Mississippi River.
The federal agency said nearly a dozen consumers in Mississippi fell ill with norovirus after eating raw oysters from the affected area March 10.
The Louisiana Department of Health and Hospitals has recalled oysters harvested from Area 7 March 6-24 and has closed the area to harvesting. Officials said they have not yet identified the source of pollution that might have caused the contamination.
The FDA said consumers who are uncertain about the origin of oysters they have in their possession should contact the place of purchase to determine if the oysters are from the affected area.