Officials in New Zealand investigating Hepatitis A cases linked to berries have identified a connection with a past outbreak in Europe.

There are 12 hepatitis A infections from eating frozen berries in New Zealand. Eight have been linked by genetic sequencing, meaning they were likely exposed to the same source of the virus. Seven people have been hospitalized. The virus attacks the liver. The Ministry for Primary Industries (MPI) was informed by the Ministry of Health of three Hepatitis A cases in September.

Foodstuffs Own Brands has recalled various Pams brand frozen berry products because of a possible link to the hepatitis A cases. Products are being removed from New World, Pak’n Save and Four Square shops nationwide, and from Trents and Raeward Fresh stores in the South Island.

All batches and dates of Pams brand Mixed Berries 500-gram, Two Berry Mix 1-kilogram and 750-gram, Smoothie Berry Mix 500-gram, and raspberries 500-gram and 350-gram are involved.

Vincent Arbuckle, New Zealand Food Safety deputy director-general, said the agency was asking people to look in their freezers for the recalled product.

“People who have these products at home should not eat them raw. Bringing them to the boil will make them safe, or they can be returned to the place of purchase for a full refund. It is important to note the situation is still evolving and the picture could change. Our advice to all consumers in the meantime is to continue to exercise care and take extra precautions at home by heat treating frozen berries to kill the virus,” he said.

Hepatitis A is relatively rare in New Zealand with the 12 cases so far accounting for half of the reported infections in the country this year. New Zealand is heading toward the summer months when more frozen berries are likely to be consumed.

Suspicion falls on frozen berries from Serbia
The virus in New Zealand is a genetic match to one which caused illness in Sweden in 2020 and 2021.

“That illness had a possible link to frozen berries from Serbia. The recalled products contain berries from Serbia and were reported as eaten by most of the people who have become sick. We were able to identify the recalled products by matching the onset of the illness with the food history reported by the cases,” said Arbuckle.

“Tracing the illness back to specific products in the case of frozen berries from imported sources is widely accepted to be a very challenging process. The 12 cases report eating a range of berries. In addition, hepatitis A has a long incubation period — up to 50 days between consumption of the product and symptoms appearing.”

Product testing by the Institute of Environmental Science and Research (ESR) has not yet identified any hepatitis A virus.

Other frozen berry importers have placed on hold products that can be traced back to Serbia while the investigation continues.

“These products have a weaker link to the cases and contain fewer berries from Serbia. We support the importers’ voluntary decision to place them on hold from sale while our work to identify the source of infection continues. It is an imposition for them, but like us, they have prioritized the safety of consumers,” said Arbuckle.

Hepatitis A virus is inactivated by heating to above 85 degrees C (185 degrees F) for one minute. Washing frozen berries will not destroy the virus. 

The virus is spread when someone ingests the virus through close contact with an infected person or by having contaminated food or drinks. Symptoms include inflammation of the liver, fever, low appetite, nausea, vomiting, diarrhea, muscle aches, and yellowing in the whites of the eyes and the skin (jaundice).