Several countries in the European Union have observed an increase in reported cases of hepatis A genotype 1B. In particular, Austria, Czechia and Hungary have observed more reported cases than expected between November 2024 to May 2025.
The increase of HAV infection is mainly affecting adults that are experiencing homeless, people with a drug addiction and people living in poor sanitary conditions. Two genetically closely related clusters of HAV 1b have been identified (cluster a and cluster b).
The chain of transmission is ongoing, and new cases are likely to occur.
Vaccination against hepatitis A is recommended for people visiting friends and relatives in remote rural areas and/or where hygiene conditions are poor as well as for risk persons, see SOP hepatitis A at www.healthytravel.ch PRO version.