Raw Oyster Illness Outbreak Hits Oregon, Washington, And British Columbia

At least 14 cases have been identified in Oregon during the past few days.

Downing a raw oyster Photo courtesy: vollan.ca

(SALEM) - In the wake of a sharp increase of illnesses associated with eating uncooked oysters, Oregon public health officials are warning the public of their potential health risk.

Most report eating raw oysters at restaurants in Portland or Medford. One ate oysters that were privately harvested in Washington State. In the past week, more than 15 cases have also been reported among residents of Washington and British Columbia.

All are linked to raw oyster consumption, according to Paul Cieslak, M.D., communicable disease manager in the Oregon Department of Human Services Public Health Division.

"These most recent cases are a reminder that uncooked shellfish are a recurrent source of illness in the Pacific Northwest," said Cieslak, "It's the same story as with meat and poultry--if you eat it raw or undercooked, there is a real risk of getting sick with some pretty nasty bugs."

Vibrio parahaemolyticus is a bacterium that is naturally present in many marine waters, including those of the Pacific Coast. Sporadic cases and occasional outbreaks associated with raw oyster consumption are reported every year, and almost all reported cases have a history of eating raw oysters within the day or two before illness onset, Cieslak said.

The symptoms of Vibrio parahaemolyticus infection include watery diarrhea, cramps, vomiting and fever. Most cases resolve without treatment. Cieslak advises that anyone sick enough to need medical attention for these symptoms should tell their doctor if they ate raw oysters or other shellfish.

Public health officials are currently working to identify the harvest sites for the oysters involved in this most recent outbreak, Cieslak said.