The European Food Safety Authority (EFSA) and the European Centre for Disease Prevention and Control (ECDC) have issued a second update on an outbreak of hepatitis A virus (HAV) infection in eleven EU member states.
The outbreak has now affected at least 1,315 people since January 2013 and 240 of these have been confirmed as being caused by the outbreak strain of the virus by genetic analysis. Originally the outbreak was thought to be associated with travel to Italy, but cases with no travel history have since been reported in France, Germany, Ireland, Norway, the Netherlands, Sweden and the UK.
Epidemiological, microbiological and environmental investigations indicate that the outbreak is associated with consumption of frozen berries and is probably a single outbreak linked to a common, continuous source. However, the investigators have not ruled out the possibilities of cross contamination in a food production environment, or a widespread, but previously undetected, outbreak strain.
Despite an extensive trace-back exercise the source of the outbreak has not yet been identified, although recent cases in new countries (France, Norway and Sweden) will be included in the on-going investigation and may produce new leads. In the meantime member states are advised to consider promoting national mitigating measures, especially heat treatment of frozen berries to destroy HAV before consumption and enhanced HAV surveillance.
The EFSA/ECDC update can be found in full here.