CONCORD (CBS SF) — A Contra Costa County case of hepatitis A appears to be linked to a recently recalled batch of frozen berries sold at Costco stores, county health officials said Sunday.

A 62-year-old woman from East Contra Costa County was hospitalized with hepatitis last month and has since recovered, said health services spokeswoman Kate Fowlie.

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The woman bought the Townsend Farms Organic Antioxidant Blend of frozen berries sold at Costco that was the subject of a multi-state recall last week and her illness and probably connected to the berries, Fowlie said.

Around 30 people in five states including California have become ill as a result of eating the berries, which are a frozen mix of cherries, blueberries, pomegranate seeds, raspberries and strawberries. Costco has removed the berries from its shelves since the outbreak and is alerting consumers who have bought them since February not to eat them.

Around 2,100 bags of the berries have been sold in Contra Costa County alone since February, Fowlie said.

Health officials are still investigating whether the berries might be sold at other stores. There is also some concern that restaurants and other food service providers might have purchased the berries and fed them to customers.

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Anyone who has purchased the berries should avoid eating them.

Those who have eaten them within the past 14 days should contact their health care provider about getting vaccinated to help prevent illness.

Hepatitis A can start two to six weeks after exposure, and symptoms include dark yellow or brown urine, yellowing of skin and the white parts of the eye, diarrhea or light-colored stool, fever or chills, loss of appetite, nausea and vomiting, upset stomach, stomach pain in the upper right side of the belly and fatigue.

Hepatitis can be mild, especially in children, or severe enough to require hospitalization. Those who have had it before or who have been immunized are probably immune.

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