California Department of Health Issues Warning on Consuming Raw Oysters Harvested From Carlsbad Aquafarms

SACRAMENTO -- Consumers should not eat raw oysters harvested since July 17, 2004 from Carlsbad Aquafarms in Carlsbad in San Diego County because they may be contaminated with the harmful bacteria Vibrio parahaemolyticus, which can lead to severe illness, State Public Health Officer Dr. Richard Joseph Jackson warned today.

The company has voluntary recalled the product, which was sold to distributors in Southern California and then resold to restaurants in Southern California and to distributors in Washington and Utah. Oysters were also sold directly to consumers by Carlsbad Aquafarms. The amount of product sold is under investigation.

The California Department of Health Services (CDHS) and San Diego County health officials are investigating six cases of gastrointestinal illnesses associated with consumption of raw oysters from this facility. Two individuals tested positive for Vibrio parahaemolyticus after consuming oysters harvested from Carlsbad Aquafarms after July 17. Oysters from the harvesting area, which has been closed, are being tested by CDHS.

Consumers with concerns about this product should contact their oyster retailer for information on the product source.

Vibrio parahaemolyticus infections can cause diarrhea, abdominal cramps, nausea, vomiting, headache, fever and chills. Symptoms generally begin within four to 48 hours after eating foods contaminated with Vibrio parahaemolyticus. Most individuals recover without treatment within two to four days. Severe cases may require medical treatment, although Vibrio parahaemolyticus infections are rarely fatal. Individuals who are at high risk of severe illness include those with chronic liver disease, cancer, AIDS or other conditions that weaken or compromise the immune system. Consumers who have recently eaten raw oysters and are experiencing symptoms mentioned above should contact their physician.

The number of Vibrio parahaemolyticus bacteria can increase in shellfish growing areas when warm summer temperatures and changes in the salt water occur. These conditions, in conjunction with inadequate refrigeration of shellfish following harvest and during transport and storage, can allow the bacteria to multiply to abnormally high levels that may result in illness.

High levels of Vibrio parahaemolyticus bacteria in shellfish pose a health risk to all consumers who eat them raw or lightly cooked, such as shucked, on the half-shell, steamed, marinated as in cevich or as in Oysters Rockefeller. CDHS recommends that oysters be cooked to a minimum internal cooking temperature of 145 degrees to destroy the bacteria.

Source: California Department of Health Services