When Townsend manufactured and Costco sold Hepatitis A – tainted berries, they likely did not know how far the problem would spread.

Hundreds of Bay Area residents received warnings Wednesday that their Target medicine purchases may be contaminated with hepatitis A after a pharmacist at two East Bay stores worked after being infected with the virus.

The pharmacist contracted hepatitis A about a month ago and may have spread it to Target customers two Alameda County Target stores. The pharmacist worked at both the Hayward location on Whipple Road and the San Leandro store on East 14th Street.

Alameda County Public Health officials said the pharmacy worker was infected with the virus after eating frozen berries bought at a Costco store.