A new vaccine aimed at protecting against norovirus, the common stomach bug causing vomiting and diarrhoea, is set to be trialled on around 25,000 adults, primarily over 60s, across more than six countries over the next two years. This highly contagious winter virus affects people of all ages, leading to widespread issues such as school and work absences and even hospital ward closures.

If successful, researchers say the vaccine could significantly reduce hospital admissions for vulnerable adults during the winter months, easing the burden on healthcare systems like the NHS. Developed by Moderna, this mRNA vaccine works by teaching the immune system to recognise norovirus and respond by producing antibodies. Unlike flu and COVID-19, which have established vaccines, this would be the first vaccine against norovirus.

The trial, backed by the UK Government, the National Institute for Health and Care Research (NIHR), and Moderna, will involve 27 NHS hospitals and centres across England, Scotland, and Wales. Half of the participants will receive the vaccine, while the others will serve as a comparison group, allowing researchers to evaluate effectiveness and monitor any potential side effects.

The impact of norovirus on the UK is substantial, with nearly four million people infected annually, leading to 12,000 hospital admissions and costing the NHS approximately £100 million each year. If proven effective with at least 65% efficacy, this vaccine could ultimately be extended to protect children, with researchers working to gather robust data for regulatory approval.