Disease, not pearl, in some raw oysters

Published April 25, 2007

Before you douse that raw oyster with fresh lemon and hot sauce, ask yourself these questions, courtesy of the Pinellas County Heath Department:

Do you have liver disease?



Any ailment that weakens your immune system?

If so, then eating raw oysters could kill you because of Vibrio vulnificus, a naturally occurring bacteria found in oysters.

It happened recently.

An elderly Pinellas County woman who contracted Vibrio vulnificus by eating raw oysters died early this month, said Jeannine Mallory, county Health Department information officer. Citing medical privacy laws, she would not give details about the woman, where she lived or where she ate the oysters.

"This is the time of the year that people eat raw oysters," she said. "It's very important for people in the high-risk groups to notice."

It's also when the Gulf of Mexico becomes a warm breeding ground for the bacteria.

Vibrio vulnificus is not contagious but can be contracted by eating raw oysters, or by swimming or wading with an open sore or scratch in seawater where the bacteria is present.

"It doesn't affect healthy people," said Ken Moore, executive director of Interstate Shellfish Sanitation Conference, a national organization that establishes guidelines for shellfish safety programs. "Those with liver disease and diabetes are the two groups of people that seem to be affected the most often."

Last year, there were 24 reported cases of Vibrio vulnificus in Florida, said Dr. Roberta Hammond of the state Department of Health. Of those, 11 were from unknown exposures, eight were from wound exposure, four from eating oysters, and one was from eating a crab.

Two of the open-wound exposures were in Pinellas County, Hammond said.

And there were two deaths in the state, both from eating oysters.

"Most of the illness are from open wounds and cuts but the deaths are from oyster consumption," said David Heil, the bureau chief with the Florida Department of Agriculture and Consumer Service in Tallahassee. "The extremely ill are not fishing and swimming. But they do eat."

Heavy drinkers with liver damage, and those with diabetes, cancer, stomach disorders or anything that weakens the immune system should be cautious.

The harmful bacteria can be killed by frying, stewing or roasting the oysters. To ensure consumers are aware of the hazards, a warning is required on all oyster packages and must be posted in restaurants or on their menus, Heil said.

"The message we are trying to get out is, 'Just don't take the risk and eat raw oysters,' " Heil said of the those in high-risk groups. "Eat them cooked."

Symptoms include mild nausea, vomiting or diarrhea, followed by swollen skin lesions and blood poisoning.

"It's a pretty mean illness,' Moore said. "It's more than your typical diarrhea and nausea."

At Cooters Raw Bar and Restaurant on Clearwater Beach, a warning at the front door and on all menus cautions those with weakened immune systems against eating raw oysters.

Cooters manager Ray Ross said care is taken to ensure the oysters are up to par. He said they are stored at the correct temperature, and tickets listing when and where the oysters were harvested remain with them to ensure they are not served after 14 days. He said proper room temperature and employee handling of the live shellfish also is of the utmost importance.

"But in the end, you want to use your senses - your eyes and your nose," Ross said. "You want to make sure that the oyster looks right and smells right and that they are still alive when shucking."

Fast Facts:

About Vibrio vulnificus

What: A naturally occurring bacteria found in oysters.

How you get it: By eating raw oysters, or swimming or wading in water when you have an open wound.

Who's at risk: Heavy drinkers with liver damage, and people with liver disease, diabetes, cancer, stomach disorders or anything that weakens the immune system.

Symptoms: Mild nausea, vomiting or diarrhea, followed by swollen skin lesions and septicemia, or blood poisoning.

To learn more: Visit www.doh.state.fl.us and click on "food and waterborne disease."