The Food and Drug Administration says consumers should avoid eating raw oysters harvested from San Antonio Bay in Texas because more than two dozen people in Maryland became ill last month.

The FDA said 25 people developed nausea, vomiting, diarrhea and other symptoms after eating raw Texas oysters at a food event in Maryland during Feb. 9-11.

Testing by the Maryland Department of Health and Mental Hygiene indicated they had contracted norovirus, the FDA said. The virus can cause flu-like symptoms that may linger for several days.

The oyster beds in San Antonio Bay were shut down by the Texas Department of Health Services on Feb. 24 and remain closed while the FDA investigates.