the santa cruz costco has been administering free hepatitis a vaccinations to customers. the free injections became available after a tainted food product was traced back to the store. as of last friday costco was out of the vaccine,but is reimbursing people for the cost of receiving the shot elsewhere. moreof the hepatitis a vaccine is expected earlythis week. if it is administered within 2 weeks of exposure it can prevent infection by the virus.