Some 15 people are now suspected of having contracted hepatitis A from imported frozen berries while two others are suspected of having contracted the virus from infected people, the Food Safety Authority of Ireland (FSAI) has said. The outbreak has led to a more than doubling of the number of hepatitis A cases in the State this year.
The people who contracted the disease from frozen berries are from all over the State, ranging in age from 25 to 58, and no common link has been established between them.
Yesterday the FSAI said it still had not identified the source of the outbreak and repeated its advice to boil all imported frozen berries for at least one minute before eating. It also urged the food service sector to exercise care in its use of frozen berries. The berries are often used in the production of fruit smoothies, yogurts, desserts and other confectionery.
The authority has not ordered a withdrawal of imported frozen berries as no common food source has been identified, and the virus has not been detected in any food samples from this State that have been sent for testing.
In mid-July it emerged that five people had contracted hepatitis A from imported frozen berries. The strain of the virus was linked with an outbreak in Italy. There have also been foodborne outbreaks of different strains of hepatitis A linked to frozen berries in Scandinavian countries and across the United States.
FSAI chief executive Prof Alan Reilly said the Italian authorities had detected the virus in samples of frozen mixed berry products imported from a number of different countries.
"Investigations suggest it is unlikely that fresh Irish or fresh imported berries are a cause of the outbreak. However, we suggest that – as with all other fruit and vegetables – fresh berries should be washed thoroughly if they are being eaten uncooked."
He said success in tracing the source of the outbreak has been hampered by the fact that it could take up to 50 days for the illness to manifest itself. “It is so difficult for people to remember exactly what they ate with any degree of accuracy over the 50-day period in which they might have been infected and this makes it hard to pinpoint a suspect food or batch of food,” he said.
Prof Reilly said the investigations were also hampered by the lack of a laboratory in this State to identify hepatitis A in foods. Suspect food samples were being sent to Italy for testing while a UK laboratory was helping to identify whether strains were related or were likely to come from a common source.
“The situation is far from ideal,” he said. “Ireland urgently needs a food laboratory with the capability to assist us to better understand the molecular epidemiology of foodborne viruses such as hepatitis A.”
For information about the hepatitis A outbreak see: fsai.ie/ faqs/berries_Hepatitis_A.html