Seasonal epidemics of respiratory syncytial virus (RSV) have a significant health burden in children in the UK. RSV is spread through droplets from the nose and throat of infected people or contact with fomites (infected objects and surfaces). The virus is active year-round, with its transmission predominant in the winter months. RSV is a common respiratory pathogen that causes infection of the lungs and respiratory tract. In adults and healthy older children, symptoms include a runny nose, coughing, sneezing and fever — similar to those of the common cold. However, in premature babies, RSV infection can be very severe and requires urgent medical treatment.
According to NHS England, premature babies are three times more likely to visit the hospital and 10 times more likely to need urgent medical care compared to full-term babies. NHS England had now taken an initiative to immunise all premature babies to prevent serious complications of RSV.
RSV illness has a significant global burden and is the second leading cause of death in children under the age of one year. In the UK, 30,000 children under the age of five are hospitalised with RSV, and it causes around 30 infant deaths each year. According to GlobalData, in the UK in 2025 there will be more than 750,000 seropositive prevalent cases of RSV in newborn children. However, these cases will likely be an underestimate if the number of RSV infections increases sharply and out of season.
NHS England estimates that thousands of premature babies will be protected against RSV in the winter of 2025/26, with a single long-lasting vaccine (nirsevimab) available on the NHS for the first time. Approximately 7,000 high-risk premature babies will be vaccinated, preventing an estimated 350 hospital admissions. Dr Claire Fuller, co-national medical director for NHS England, states: “This injection will provide premature babies with a protective bubble against RSV just in time for the colder months. It will offer a long-lasting defence, helping to avoid unnecessary hospitalisations and serious illness – giving babies the best possible start in life and shielding them from harm.”
RSV is a highly infectious disease, and virtually all children will have been infected with RSV by the age of two. However, the complications of RSV are often mild or nonexistent except for those with specific risk factors that make them more prone to the severe complications of RSV, which can include pneumonia, bronchiolitis and potentially death. The most common risk factors for severe RSV include being born preterm, being elderly, having chronic lung disease or congenital heart disease, and having a weakened immune system. Understanding the spread and potential life-threatening symptoms of RSV is critical in curbing and limiting the exposure of those who are at greatest risk of severe complications from RSV.