San Diego County public health officials announced Thursday they are expanding their investigation of oyster-related illnesses to all oysters harvested in Mexico.
Health officials are advising consumers and restaurants to destroy oysters imported from within Mexico until further notice.
The local norovirus outbreak currently includes 69 confirmed and probable cases, according to the county Health and Human Services Agency. The severity of the outbreak in San Diego County remains mild, with no hospitalizations reported to date. Initial investigations identified 41 probable and confirmed cases of norovirus infection associated with oysters harvested in the Mexican state of Sonora. The cases so far have been linked to oysters served at three The Fish Shop locations in Pacific Beach, Point Loma and Encinitas, as well as Carlsbad Aquafer. An additional 28 people were infected, including 20 who ate oysters from other restaurants.
“The County recommends that you ask where your oysters were harvested when eating out or purchasing food from a wholesaler to avoid consuming oysters imported from Mexico,” County Public Health said. said Dr. Ankita Kadakia, deputy director of the department. “Norovirus is usually a mild illness, but it can cause dehydration, especially in young and elderly people.
“Given the rising number of cases, it is also likely that there are people in the same household who are at higher risk of developing severe disease,” Kadakia said. “We would like to remind those who have become ill and their household members to wash their hands frequently to avoid contaminating surfaces and food that could further spread the infection.”
Oyster-related norovirus cases have also been reported in Orange, Riverside, San Bernardino, Ventura and Los Angeles counties, the county said. The California Department of Public Health and the U.S. Food and Drug Administration are currently actively investigating.
The FDA, which has jurisdiction over oysters imported into the country, issued its first advisory on Jan. 11 based at least in part on the findings of a study conducted by county health officials, according to a statement from the county.
On Wednesday, the FDA subsequently issued a second advisory for Lakes de Guerrero Negro and Lake Manuela, which are located on the Pacific coast of Mexico's Baja California but geographically distant from the state of Sonora. On Thursday, the FDA updated its initial advisory regarding Sonoran oysters to include a second harvest site, Estero Morua.
The new FDA advisory advises restaurants and retailers to destroy any remaining oysters or contact the retailer to arrange a return or disposal. Those who have them at home should do the same.
“All of the implicated oysters were harvested in December 2023, and no oysters have been distributed to San Diego restaurants from those locations since then,” the county's statement said. .
Eating raw or undercooked oysters can make you sick from the bacteria in the oysters.
People infected with norovirus typically develop nausea, vomiting, diarrhea, stomach cramps, fever, and body aches 12 to 48 hours after consuming contaminated food. The illness usually lasts 1 to 3 days. Vomiting and diarrhea can lead to dehydration that requires medical attention, especially in young children, the elderly, and people with other illnesses.
HHSA continues to work with the California Department of Public Health, including the Shellfish Program, to investigate oyster-related illnesses. To report an illness to the county after eating out or purchasing at a wholesale grocery store, call 858-505-6814 or email fhdepi@sdcounty.ca.gov.
