The UKHSA study, Maternal RSV vaccination and reduced risk of hospitalisation for babies in England 2024/25, found vaccination at least two weeks before birth gave 81.3% protection.

Matt Wilson, epidemiologist at UKHSA, presenter and lead author, said: ‘Our evaluation of the first season of the programme in England gives important confirmation that maternal RSV vaccination is highly protective for newborn infants, over 80%, and that effectiveness reached nearly 85% when vaccination occurred at least four weeks before birth.'

The maternal vaccination programme is offered to women from 28 weeks of pregnancy to protect newborns.  

The study followed nearly 300,000 babies born between September 2024 and March 2025, representing around 90% of all births in England during this period. More than 4,500 hospitalisations occurred in this cohort, the vast majority in infants whose mothers had not been vaccinated.  

Getting the vaccine on time was best (in week 28 or soon after that), as babies born at least four weeks after their mother was vaccinated had nearly 85% protection. Vaccination later in pregnancy also gave some protection, with vaccination as close as 10 to 13 days before birth reducing hospital admissions by 50%.  

The study, which will be presented on 18 April at the European Society of Clinical Microbiology and Infectious Diseases (ESCMID) global conference, also found that premature babies, who are particularly vulnerable to RSV, can be well protected, provided there is at least two weeks between vaccination and birth.  

RSV vaccine uptake in England was 55% during the study period and the latest data show uptake rising to 64.1% for women who gave birth in November 2025.