The late-stage trial will recruit about 25,000 people around the world to test the new vaccine from Moderna. A first-of-its-kind study testing an mRNA vaccine for norovirus, the highly contagious winter vomiting bug, is launching in the UK and around the world. Norovirus, which causes vomiting and diarrhoea, is usually the result of a viral or bacterial infection and typically peaks in the colder months.

There’s no vaccine or specific treatment for norovirus, and while most people get better within a few days, it can make young people, older adults, and those with weakened immune systems very sick. The new late-stage clinical trial will identify how well the vaccine protects against moderate to severe illness and will recruit about 25,000 adults in the UK, US, Canada, Japan, Australia, and South American countries, according to the UK’s National Institute for Health and Care Research (NIHR). Most participants will be aged 60 or older, while 5,000 will be aged 18 to 59.

US patients have already begun receiving the vaccine. In the UK, about 2,500 people will be recruited between late October 2024 and early 2025, NIHR said. "Outbreaks of norovirus have huge consequences, both on our health systems and our economy," Dr Patrick Moore, co-director of clinical trial network Wessex Research Hubs and head of the UK study, said in a statement.

"This innovative trial is crucial in helping us advance healthcare". Worldwide, there are about 685 million cases of norovirus per year, and.