Europe – Norovirus Ongoing Outbreak in Frozen Berries Report -Hepatitis A

EurosurvaillanceClose up 3d render of an influenza-like virus isolated on white

A food-borne outbreak of hepatitis A in Denmark was notified to other countries on 1 March 2013. A case–control study identified frozen berries eaten in smoothies as potential vehicle. In the following weeks, Finland, Norway and Sweden also identified an increased number of hepatitis A patients without travel history. Most cases reported having eaten frozen berries at the time of exposure. By 17 April, 71 cases were notified in the four countries. No specific type of berry, brand or origin of berries has yet been identified.

As of 17 April 2013, 36 cases, of whom 15 were confirmed, have been identified in Finland, Norway and Sweden, giving a total of 71 cases in the four countries (Table 1). Finland and Norway have reported confirmed cases with sequence 1 and 2. In Sweden, two of the eight confirmed cases have an HAV IB sequence with 2% difference to sequence 1 and 1% difference to sequence 2 (called sequence 3).
The overall median age for cases and the median age for confirmed cases is 25 years (range: 3–78 years); 43 cases are female. In Norway and Sweden (but not Finland), more women are affected than men. The distribution of cases by month and HAV sequence type is shown in Figure 1. As of 17 April 2013, Sweden is the only country with cases with symptom onset in April. An increased number of travel-related hepatitis A patients in the same time period (Table 1) may be explained in part by patients infected in Egypt [1].

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