Outbreak of hepatitis A under investigation
A national outbreak of hepatitis A is currently under investigation in Ireland and is likely to be due to the consumption of a contaminated food item. To date, 16 outbreak cases have been identified, one of which is a secondary case. The virus strain is identical to that of a large outbreak of hepatitis A genotype IA in Italy this year that has been linked to imported frozen mixed berries. The investigation in Ireland is being carried out by the HSE Health Protection Surveillance Centre (HPSC), in collaboration with the Food Safety Authority of Ireland (FSAI), the National Virus Reference Laboratory (NVRL) and the HSE Departments of Public Health and Environmental Health.
No definitive food source of the outbreak has yet been identified. It can be difficult to identify the source of outbreaks of hepatitis A as there is a long interval between exposure to the virus and subsequently becoming ill (up to 50 days). Cases have been interviewed about their food consumption and a study is being carried out to compare food histories of cases with those of a control population who are well. FSAI is coordinating the environmental investigation based on information from the food histories, with the focus primarily on the supply chain of imported frozen berries.
As a precautionary measure, boil all imported frozen berries for at least one minute before consumption. Make sure to wash all fresh berries, and other fruit and vegetables if eating them uncooked.
Further information available:
Summary report on the outbreak: Outbreak of hepatitis A virus under investigation in Ireland
Food Safety Authority of Ireland: Advice to consumers
Protection Surveillance Centre: Information on hepatitis A