Virology

Why the Hepatitis E Virus Cannot Infect Mice

Many viruses can infect both humans and animals, including hepatitis E virus. This virus is often transmitted to humans via contaminated meat products, such as when ingesting raw or undercooked pork or wild game. However, while mice have been believed to be resistant to infection, the underlying reason for this was unclear. The team of researchers from the Ruhr University Bochum Department of Molecular and Medical Virology, Germany, has now investigated the viral replication cycle in detailand discovered that the species barrier in mice is defined at the point of viral entry into the cell. First author Dr. Nicola Frericks and her team of researchers report their findings in the journal Emerging Microbes & Infections from July 27, 2026.

Genetic material is not unpacked

It has long been known that the hepatitis E virus cannot establish an infection in mice, but the reasons were unknown. The virology research team in Bochum therefore systematically examined the replication cycle of the virus in liver cell cultures of mice. “We observed that most processes of viral infection also function in mouse cells,” reports Frericks. Viral particles attached to murine hepatocytes andnew virus particles could also be formed and released from the host cell if viral entry was bypassed. “But functional cell entry is blocked,” the scientist continues. “Even when our findings indicate that the virus particles are imported, the viral genetic material is likely not unpacked in the mouse cells.”

This is important for a variety of reasons: For one, it improves our understanding of the host range of this zoonotic virus and help assess the risk of transmission to other animal species. Secondly, it could pave the way for establishing a mouse model to study the disease. “This would be immensely helpful in testing therapeutic approaches,” says Frericks. “There is still no specific, effective treatment for hepatitis E.”