The outbreak, which has affected at least 71 people so far, has been linked to frozen berries in smoothies.
An outbreak of hepatitis A in four Northern European countries has been linked to frozen berries in smoothies, although there is still no solid evidence that points to the specific products and their origin, according to a report published by Eurosurveillance.
The outbreak started in Denmark and spread to Finland, Norway and Sweden. At least 71 people have been affected so far, the European Center for Disease Control and Prevention (ECDC) said. The outbreak is believed to have started in October 2012 and continued through April 2013. Three in four of those affected are female and the age of the patients ranges from 4 to 62, with a median age of 30.5 years old, the center stated.
None of the affected patients had any history of traveling outside the EU that could be linked to the disease, limiting the potential exposure to Europe only. According to the ongoing investigation, the foodborne transmission of the virus came from a common source and consumption of frozen berries as an ingredient in products is the most likely cause. Investigators found that 18 of the people with the virus had eaten frozen berries prepared as smoothies, while 20 others reported eating frozen strawberries. So far no specific type of berries or a brand have been identified as the source of the contamination.
Health authorities in the four affected countries have advised consumers to boil all frozen berries before consumption as a precautionary measure, even though investigators have not firmly concluded that they are the source of contamination. Similar hepatitis A sequences were detected in Canada, France and the Netherlands in March but those cases were linked to traveling to Egypt. In 2012, norovirus from Chinese strawberries sickened 11,000 schoolchildren in Germany, the ECDC revealed.
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Hepatitis A is an infection that affects the liver and it can sometimes be hard to identify as in certain cases the disease has no symptoms, especially in young children. Generally, symptoms may include fever, nausea, vomiting, abdominal pain, loss of appetite and fatigue. Sometimes patients report a yellowing of the skin and eyes, known as jaundice. People who experience some of these symptoms are advised to contact a healthcare provider for examination. The incubation period of the disease is 28 days, the ECDC explained.
The disease is transmitted from person to person and this usually takes place when someone consumes food or drinks contaminated by a person who has the virus. It is not spread by coughing or sneezing or by casual contact, health experts say. Typically, complications from the disease are rare but they can occur, especially among people with liver disease or a weakened immune system. People are advised to thoroughly wash their hands after visiting the restroom and before handling food and drinks.