A multidisciplinary international team of public health and food safety experts from 13 European countries has published a report of its investigation into a multistate outbreak of hepatitis A infection that affected people across Europe in 2013 and 2014.
The outbreak was first reported in May 2013 when the Italian authorities declared a national outbreak of hepatitis A, which also affected tourists from other countries. Molecular typing of viruses from some of the cases identified a strain of hepatitis A virus subgenotype IA. Other European countries then reported locally acquired cases caused by the same strain and an international outbreak investigation was initiated.
By August 2014 1,589 related cases had been identified and over 1,000 of those affected had required hospital treatment, with two associated deaths being reported. Epidemiological and microbiological evidence from the investigation suggested that the source of the outbreak was consumption of frozen mixed berries. Some implicated products were recalled and consumers were advised to heat-treat berries before consumption.
The Investigation report identifies frozen berries as a high-risk food, highlighting the increasingly susceptible European population and the growing globalisation of the food supply as important risk factors.
The investigation report is published in the journal Eurosurveillance and can be accessed in full here.