It’s Spring – Do You Know Where Your Oysters Are From?

Everyone loves the warmer temperatures that come with spring. Unfortunately, so does Vibrio vulnificus — a bacterium that can seriously sicken or even kill people who eat raw, untreated, contaminated oysters from Gulf Coast states including Alabama, Florida, Louisiana and Texas.

San Diego County environmental health officials are reminding people, restaurants and other eateries not to eat or prepare raw Gulf Coast oysters unless they have been treated to reduce bacteria levels.

California law requires all raw Gulf Coast oysters that are harvested each year between April 1 and Oct. 31 to be treated to reduce Vibrio vulnificus to non-detectable levels before they can be sold.

Vibrio vulnificus is found naturally in seawater environments and typically in its highest concentrations in Gulf of Mexico waters during warm spring and summer months.Every year people get seriously ill and die after eating raw Gulf Coast oysters.

California has required restaurants and markets to prominently display warning signs since 1991 about the risks of eating oysters harvested from the Gulf of Mexico. These signs are not required in establishments that only sell treated raw Gulf Coast oysters.

According to the National Centers for Disease Control and Prevention (CDC), healthy people who eat untreated contaminated oysters can suffer vomiting, diarrhea and abdominal pain. However, people who already suffer from weakened immune systems can develop bloodstream infections that are fatal in nearly half of all cases.

Here are some tips for how to prevent Vibrio vulnificus infections:

  • Do not eat raw oysters from Gulf Coast states from April 1 through Oct. 31.
  • Ask if oysters are pre-treated before you buy them.
  • Avoid cross-contamination of foods whenever working with raw seafood and juices from raw seafood.
  • Remember to thoroughly wash your hands or wear a clean pair of gloves when handling raw shellfish.

To find more information about Vibrio vulnificus call the San Diego County Department of Environmental Health’s duty specialist at (858) 505-6900 or visit the websites of the California Department of Public Health and the CDC.




Gig Conaughton is a communications specialist with the County of San Diego Communications Office. Contact