The US Food and Drug Administration said customers should not eat raw oysters from an area of the southern tip of Hood Canal in Washington. FDA has reasons to believe that the oysters have caused an outbreak of illness caused by Vibrio parahaemolyticus bacteria.

According to FDA, the symptoms of the illness, called Vibirosis, are diarrhea, abdominal cramping, vomiting fever and chill.

The FDA said anyone who may have experienced these symptoms after consuming raw oysters should consult a health care provider and contact the local health department.

Until now, FDA received reports about at least six people in California and Washington who came down with the illness. Severe disease is rare and occurs most commonly in people with weakened immune systems, FDA added. Additional reports are investigated.

The raw oysters were harvested from “growing area 6” in Hood Canal from July 3 and they were distributed in several states of the United States (California, Florida, Hawaii, Idaho, New York, Oregon, Washington) and in Hong Kong, Malaysia, and Singapore.

As a measure of precaution, the Washington State Department of Health has closed the growing area and advised oyster harvesters and dealers to recall them.

Also FDA said consumers who intend to eat oysters should check their provenience and order oysters fully cooked.