The CDC said Tuesday that illnesses have been reported in Arizona, California Colorado, Hawaii, Nevada, New Mexico, Utah and Washington.
Townsend Farms of Fairview, Ore., last week recalled its frozen Organic Antioxidant Blend, packaged under the Townsend Farms label at Costco and under the Harris Teeter brand at those stores. So far the illnesses have only been linked to the berries sold at Costco.
The Food and Drug Administration is investigating the cause of the outbreak. The CDC said the strain of hepatitis is rarely seen in North or South America but is found in the North Africa and Middle East regions. Townsend Farms has said the frozen organic blend bag includes pomegranate seeds from Turkey.
Hepatitis A is a contagious liver disease that can last from a few weeks to a several months. People often contract it when an infected food handler prepares food without appropriate hand hygiene. The CDC said that food already contaminated with the virus can also cause outbreaks, as is suspected in this case.
Illnesses occur within 15 to 50 days of exposure to the hepatitis A virus, CDC said. Symptoms include fatigue, abdominal pain, jaundice, abnormal liver tests, dark urine and pale stool.
Vaccination can prevent illness if given within two weeks of exposure, and those who have already been vaccinated are unlikely to become ill.
CDC said the illnesses date back to mid-March. The same genotype of hepatitis A was identified in an outbreak in Europe linked to frozen berries this year, the CDC said, as well as a 2012 outbreak in British Columbia related to a frozen berry blend with pomegranate seeds from Egypt. The agency said there is no evidence the outbreaks are related.
Costco is providing vaccinations for people who at the berries within the last two weeks. The company is reimbursing others who received the vaccine outside the store. About 240,000 people who bought the berries have been contacted by the company. The company knows who bought the berries because purchases are linked to a membership card that customers present when they check out.
The Associated Press contributed to this report.