The U.S. Food and Drug Administration on Friday advised people not to eat raw oysters harvested in Washington state, citing bacterial illnesses that have sickened at least six people in that state and California.

The state Department of Health closed the area associated with the vibriosis illness, the southern tip of the Hood Canal, and has asked commercial harvesters and dealers who obtained oysters from this area to recall them. Raw oysters from the area were distributed to California, Florida, Hawaii, Idaho, New York, Oregon, Washington, Canada's British Columbia, Hong Kong, Malaysia and Singapore. Additional reports of illnesses are being investigated by the states, according to an FDA release.

Consumers who have recently purchased oysters should check with the place of purchase and ask if the oysters were harvested from the affected area. Symptoms of vibriosis, caused by the vibrio parahaemolyticus bacteria, include diarrhea, abdominal cramps, nausea, vomiting, headache, fever and chills and usually appear within 24 hours after eating the oysters. Severe disease is rare and occurs mostly in people with compromised immune systems.

To avoid the illness, consumers should make sure the oysters are cooked at 145 degrees to kill the bacteria, according to the FDA. For more information, consumers can call the FDA at 888-463-6332 and visit www.doh.wa.gov/Publicat/2007—news/07-131.htm.