Three oyster harvesting areas in Louisiana are off limits as of Monday evening.
Health officials are trying to figure out what is causing a stomach flu outbreak.
38 cases of Norovirus have been reported from oysters fished out of St. Bernard, Plaquemines, Lafourche , and Jefferson Parishes.
The illnesses have happened in the last two weeks.
Officials are trying to determine if the problem is from contamination in the water or if someone handling the oysters passed on the virus.