The following public health alert regarding hepatitis A and frozen strawberries has been issued by the Centers for Disease Control and Prevention, Hepatitis Branch, Division of Viral and Rickettsial Diseases, NCID.

There has been a recent cluster of cases of hepatitis A in Massachusetts linked to the consumption of commercially processed frozen strawberries. Information on the harvesting, processing and distribution of the potentially contaminated frozen strawberry products is currently being investigated by the Food and Drug Administration, and will be provided in a separate communication when available.

The Boston Communicable Disease Control Division and the Massachusetts Department of Public Health are investigating 7 cases of acute hepatitis A among persons who attended an ice cream party at a hospital cafeteria on February 11 and 12, 2000. Foods served at the event included commercially prepared ice cream, and a variety of toppings including frozen strawberries, whipped cream, candies, nuts, and cherries. All 7 persons with hepatitis A became ill between March 7 and March 21, 2000. No ill food handlers have been identified, and all are negative for IgM antibodies to hepatitis A virus. A case control study that included all cases and 38 well controls who ate at the ice cream party indicated that eating frozen strawberries was the only food associated with illness (OR 36.4, 95% CI 3.8-infinity). All cases ate frozen strawberries at the party. Because no known food handlers have evidence of infection, and because the event reportedly involved little hand contact with the food served, contamination of the frozen strawberries likely occurred at some point during harvest, processing or distribution.

This investigation is ongoing and these findings should be considered preliminary. We are requesting that state and local health departments look at their hepatitis A reporting and be on the lookout for recent hepatitis A clusters or unexplained increases in cases that could be associated with the consumption of frozen strawberries. In such instances, recently identified cases of hepatitis A should be asked about frozen strawberry consumption, including frozen strawberries consumed in commercial or institutional settings. Serum specimens from persons with hepatitis A during the acute phase of their illness (e.g., the first diagnostic specimen) who report frozen strawberry consumption should be saved (frozen) for possible viral sequencing studies.

Please contact the Division of Epidemiology, Environmental and Occupational Health Services, Communicable Disease Services at 609-588-7500 if you have any questions.

c: Office of Local Health
Medical Society of New Jersey