Finnish officials are investigating the connection between a hepatitis E-positive meat product and a rise in infections in the country.

In January and February, 81 hepatitis E cases from different parts of Finland were reported to the Infectious Disease Register. Half of these people have required hospital treatment. Between 20 and 60 hepatitis E cases are reported to the Infectious Disease Register annually. In 2023, there were 30 cases. In January 2023, only one Hepatitis E infection was reported in the register.

In laboratory tests by the Finnish Food Authority (Ruokavirasto), the hepatitis E virus was found in a product made by a domestic manufacturer. These items have been recalled and are no longer on sale.

Kotivara withdrew six products sold since early November 2023 in retail stores and wholesalers. Most items have passed their shelf life date, but two last until March 19, 2024.

Of 30 patients interviewed by the National Institute of Health and Welfare (THL), 27 mentioned consuming different brands of mettwurst or salami before they got sick. However, meat products are commonly consumed foods, so clarification was needed on the significance of this finding. This was why the Finnish Food Agency examined various food samples based on the brands recorded in THL’s reports.

From 44 patients, the median age of those affected is 64 and 70 percent are men.

THL is in the process of genotyping the hepatitis E viruses found in samples from patients to compare them with the recalled positive product.

Ruokavirasto, THL, and local food control authorities are looking into the source of hepatitis E infections. This includes determining how many patients the recalled products may have caused and if there are other contaminated items.

THL has typed the hepatitis E viruses found in the samples of 13 patients. The most common genotype was HEV-3f, which formed three clusters. HEV-3f was last detected in Finland in 2019. Between 2019 and 2022, HEV-3e and HEV-3c were the most common genotypes in patient samples.

Wider EU issue
In February, the European Centre for Disease Prevention and Control (ECDC) said it was monitoring the situation after some countries reported a spike in hepatitis E infections.

More patients than usual had been seen in January in Belgium and the Czech Republic. More than 350 patients were recorded in Germany, 63 in the Czech Republic, and 36 in Belgium.

In January 2024, 520 hepatitis E virus infections were noted in 10 countries. No connection had been established between all these cases. In Belgium, genotype 3c was the most frequently identified among patients with available information. Genotyping of the virus was ongoing in Spain.

Hepatitis E infection is a liver disease caused by the hepatitis E virus (HEV). Advice to avoid infection includes thoroughly cooking all meat, especially pork, before eating it and washing hands after touching uncooked meat or meat products.

The mean incubation period for HEV is five to six weeks, with a range of two to nine weeks, and can persist for one to four weeks. Symptoms include fatigue, poor appetite, stomach pain, nausea, and jaundice. However, some people, especially young children, have no symptoms.