The investigation into two people from the same household who got sick after eating raw blue crab on Jan. 18 and 19 has been completed, according to Seattle-King County Public Health.

Since Public Health learned of the incident on Feb. 7, the investigation found one of the sick people has laboratory-confirmed Grimontia hollisae, an illness similar to vibriosis. Vibrio hollisae is organism produces toxins and also invades host’s epithelial cells, causing both gastroenteritis and septicemia.

One of the two sick people was hospitalized. Both have since recovered.

The pair said they’d eaten raw blue crab at Seafood City in Tukwila, WA. Public Health reported Seafood City had satisfactory food safety ratings and inspections at the time of the incident. Symptoms of Vibrio hollisae include nausea, vomiting, and diarrhea.

Environmental Health investigators visited Seafood City on Feb. 12. Investigators did not identify any factors that contribute to the spread of Grimontia bacteria, such as incorrect refrigeration temperatures or evidence of cross-contamination. Public Health worked with the Washington State Department of Health (DOH) Shellfish Program and Washington State Department of Agriculture (WSDA) to investigate the source of the blue crab.

About Grimontia hollisae
Grimontia hollisae is a species of bacteria within the same family and closely related to Vibrio. It was formerly known as Vibrio hollisae and resembles Vibrio parahaemolyticus in terms of where it lives and how it causes illnesses in humans.

Grimontia and Vibrio sp. are naturally occurring in marine waters. Eating undercooked or raw shellfish and other seafood such as crab is the main risk factor for getting this illness. The growth of Vibrio and Grimontia species increase in marine waters during warmer months, which usually causes an increase of the bacteria in shellfish.

Public Health’s general advice for reducing the risk of contracting Grimontia or Vibrio:

  • Because raw seafood may be contaminated with Grimontia/Vibrio or other organisms, always cook crab, shellfish and other seafood to at least 145° for 15 seconds before eating. Crab should be cooked until the flesh is pearly and opaque.
  • Wash cutting boards and counters used for shellfish/seafood preparation immediately after use to avoid cross-contaminating other foods.
  • Wash hands thoroughly with soap after handling raw shellfish/seafood.
  • Stay out of brackish or salt water if you have any wounds (including scrapes and cuts), or cover your wound with a 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.

Public-Health Seattle-King County is one of the larger metropolitan health departments in the United States serving a population of nearly 2.2 million people.

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