Raw Oyster Investigation​ Expanded After More Sickened In San Diego

SAN DIEGO, CA — San Diego County public health officials have expanded an investigation into an oyster-linked norovirus outbreak to include all oysters harvested from Mexico.

Health officials Thursday advised consumers and restaurants to throw away any oysters imported from locations in Mexico until further notice.

The San Diego area norovirus outbreak now includes 69 confirmed and probable cases, according to the San Diego County Health and Human Services Agency. The severity of the infections in the county has remained mild, with no hospitalizations reported to date.

The initial investigations identified 41 confirmed and probable norovirus cases linked to oysters harvested in Sonora, Mexico. The people who got sick ate at the Fish Shop restaurants in Encinitas, Pacific Beach and Point Loma, as well as the Carlsbad Aquafarm. Since then, 28 more cases have been added, including 20 people who ate oysters from other food venues.

Oyster norovirus cases have also been reported in Orange, Riverside, San Bernardino, Los Angeles and Ventura counties, according to the county. Both the California Department of Public Health and U.S. Food and Drug Administration are now involved in the investigation.

"The county recommends that people ask where oysters were harvested when eating out or getting food from wholesale locations to avoid consuming oysters imported from Mexico," said Dr. Ankita Kadakia, the county's deputy public health officer.

Norovirus is the leading cause of vomiting and diarrhea, and foodborne illness in the U.S., according to the Centers for Disease Control and Prevention.

"Norovirus is typically a mild illness but can cause dehydration especially for the very young and very old," Kadakia said.

"Given the increasing number of cases, the chance for others at greater risk for more severe illness in the same home is also increased," she added. "I want to remind people who become ill, and those that live with them, to wash their hands frequently to avoid contaminating surfaces and foods that could further spread the infection."

To report illness to the county after dining out or purchasing from wholesale food locations, call 858-505-6814 or email fhdepi@sdcounty.ca.gov.