More than 1,300 Hepatitis A cases have been reported in 11 countries by the European Food Safety Authority since January 2013, with 240 confirmed cases related to an ongoing outbreak. Initially the outbreak was associated with people who had traveled to Italy. However seven countires- France, Germany, Ireland, Norway, the Netherlands, Sweden and the United Kingdom- have reported cases of infections in people who had not traveled to Italy. Preliminary investigations identified frozen berries as the most likely source of infection. Other hypotheses, such as cross contamination in the food production environment or that the outbreak strain is already widespread but previously undetected, have now also been taken into account. EFSA is leading a trace-back investigation, with the support of affected Member States, the European Centre for Disease Prevention and Control, the European Commission and the Federal Institute for risk assessment (Bfr).