Increase in Vibrio parahaemolyticus illnesses associated with consumption of shellfish from several Atlantic coast harvest areas, United States, 2013
Advice to Consumers
Consumers should avoid eating raw or undercooked shellfish, especially oysters and clams, because they have made people sick.
- This is especially true among people with weakened immune systems and chronic liver disease.
- Although the risk of Vibrio illness is typically higher when shellfish are harvested from warmer waters, Vibrio can be found in seafood, including shellfish, in any month
Who is most at risk for a Vibrio illness?
- Persons who have weakened immune systems or have chronic liver disease are at higher risk of becoming ill
Symptoms of V. parahaemolyticus infection may include:
- Watery diarrhea
- Abdominal cramps
- Bloody diarrhea
- See Signs & Symptoms for more information.
Contact your health care provider for any diarrheal illness that is accompanied by:
- High fever (temperature over 101.5 F, measured by mouth)
- Blood in the stools
- Prolonged vomiting that prevents keeping liquids down (because this can lead to dehydration)
- Signs of dehydration, including a decrease in urination, a dry mouth and throat, and feeling dizzy when standing up
- Diarrhea lasting more than 3 days
Fish and shellfish can be part of a healthy diet. Following the advice below can help reduce the risk of foodborne illness:
- When ordering shellfish in restaurants, ask that they be fully cooked unless they have been treated with a method to reduce Vibrio (such as pressure treatment).
- Keep raw foods from touching cooked foods and surfaces used for cooking and eating
- Preparing oysters in the shell:
- Before cooking: Discard any with open shells
- During cooking: Boil for 3-5 minutes after shells open
- After cooking: Discard any with shells that did not open
- Preparing shucked oysters that have not been treated by a method to reduce pathogens:
- Boil or simmer for at least 3 minutes or until the edges curl
- Fry at 375 degrees for at least 3 minutes
- Broil 3 inches from heat for 3 minutes
- Bake at 450 degrees for 10 minutes