Seafood sold across six states, including Massachusetts, is being recalled after a norovirus outbreak was discovered at the product's growing area in Washington.

The U.S. Food & Drug Administration advises restaurants and food retailers to immediately throw away oysters and Manila clams harvested by Rudy's Shellfish in Washington between Nov. 15 and Dec. 11 due to the outbreak.

The recalled items were distributed in Massachusetts, New York, Minnesota, Florida, Arizona, Washington and California, though the FDA says the products may have also been sold in other states.

The agency said it will continue to monitor the situation.

Food contaminated with norovirus may look, smell and taste normal.

A mild norovirus infection causes diarrhea, vomiting, nausea and stomach pains. Other symptoms include fever, headache and body aches.

Norovirus illnesses can make "you feel extremely ill, and vomit or have diarrhea many times a day," potentially leading to dehydration, the FDA warns.

It is also "very contagious," according to the U.S. Centers for Disease Control and Prevention.

"You can get norovirus by accidentally getting tiny particles of feces (poop) or vomit in your mouth from a person infected with norovirus," the CDC said.

"If you get norovirus illness, you can shed billions of norovirus particles that you can't see without a microscope. It only takes a few norovirus particles to make you and other people sick."

You can contract the virus from sick people, through contaminated food or contaminated water and surfaces.

The CDC warns those infected with norovirus are most contagious when they are showing symptoms or a few days after feeling better.

If more information about the recall becomes available, the FDA said it will update the recall.