Foodborne illness outbreak investigation
Posted July 12, 2017
Public Health is investigating an outbreak of gastroenteritis with watery diarrhea, abdominal cramping, and vomiting associated with consumption of raw oysters at Salted Sea located at 4915 Rainier Ave S #101, Seattle, WA 98118. One person has laboratory-confirmed Vibrio parahaemolyticus and two others have symptoms suggestive of vibriosis.
Two people from one dinner party became ill after eating raw oysters at the restaurant on June 9, 2017. Another person from a separate party became ill after eating raw oysters at the restaurant on June 17, 2017. Public Health learned of the outbreak on June 22nd.
An on-site investigation was conducted at Salted Sea by environmental health inspectors. No factors were identified that contribute to the spread of Vibrio, such as insufficient refrigeration temperatures or evidence of cross-contamination. Public Health also reported the illnesses to Washington State Department of Health (DOH) Shellfish Program, which is responsible for tracking the reports and harvest locations of the oysters implicated in these illnesses. The oysters served at each of the meals were harvested from multiple growing areas/bays in Washington State. Without further information from the ill persons on the variety of oysters consumed, we were unable to pinpoint the particular growing area the oysters came from and no closures or recalls were issued. For more information, see the DOH Shellfish Program website.
Updated July 17, 2017
Since July 10th, Public Health has investigated an additional 3 separate reports of 8 total ill persons with Vibrio-like symptoms including nausea, vomiting, and diarrhea after eating raw oysters at Salted Sea. Two of the three meal parties identified one variety of oysters they consumed, which is aiding in pinpointing the particular growing area. Public Health is working closely with the DOH Shellfish program and the investigation is ongoing. With these additional reports, as many as 12 people (1 with lab-confirmed vibriosis) have become ill after eating raw oysters served at Salted Sea since June 9th, 2017.
Vibrio is a bacteria consisting of multiple species, including Vibrio parahaemolyticus. The bacteria are naturally occurring in marine waters. Eating undercooked or raw shellfish, especially raw oysters, is the main risk factor for acquiring vibriosis from infection with Vibrio parahaemolyticus. Growth of Vibrio species is amplified during the warmer months and Vibrio levels in shellfish increase during the summer.
To prevent Vibrio infection:
- Because raw seafood can be contaminated with Vibrio, always cook shellfish and other seafood thoroughly before eating.
- Wash cutting boards and counters used for shellfish preparation immediately after use to avoid cross contaminating other foods.
- Wash hands thoroughly with soap after handling raw shellfish.
- Stay out of brackish or salt water if you have any wounds (including scrapes and cuts), or cover your wound with waterproof bandage to prevent a skin infection.
Wash wounds and cuts with soap and water if they have been exposed to seawater or raw seafood and raw seafood juices, to prevent a skin infection from Vibrio.
For more information on vibriosis, see: