Vaccinating pregnant women against a virus that causes coughs and colds can “significantly” reduce the risk their babies will be hospitalised, scientists’ studies have found.
A team of researchers co-led by the University of Edinburgh said giving pregnant women the respiratory syncytial virus (RSV) vaccine led to a 72 per cent reduction in babies being hospitalised with a serious lung infection, scientists have found.
RSV can lead to a severe lung infection called bronchiolitis, which is dangerous in babies and can result in them being admitted to intensive care.
It is the main infectious cause of hospitalisation for babies in the UK and globally.
The study saw researchers examine 537 babies across England and Scotland who were admitted to hospital with severe respiratory disease in the winter of 2024-25.
A total of 391 of the babies tested positive for RSV.
The team found mothers of babies who did not have RSV were twice as likely to have received the vaccine before giving birth than the mothers of RSV-positive babies (41 per cent as opposed to 19 per cent).
They also found receiving the vaccine more than two weeks before giving birth increased the level of protection, with a 72 per cent reduction in hospital admissions in this group compared with 58 per cent for babies whose mothers were vaccinated at any time prior to delivery.
The RSV vaccine was introduced across the UK in the late summer of 2024.
The scientists said it works by causing the mother to produce antibodies – proteins which help prevent the virus causing severe infection – which are then passed to the fetus, providing protection from severe RSV for the first six months of their child’s life.
They recommend women get vaccinated as soon as possible from 28 weeks of pregnancy to provide the best protection, as this allows more time for the mother to generate and pass on protective antibodies to the baby, but the jab can be given up to birth.
They also said previous research shows only half of expectant mothers in England and Scotland are currently receiving the RSV vaccine, despite its high success at preventing serious illness.
Study lead Dr Thomas Williams, from the University of Edinburgh’s Institute for Regeneration and Repair, said: “With the availability of an effective RSV vaccine shown to significantly reduce the risk of hospitalisation in young infants in the UK, there is an excellent opportunity for pregnant women to get vaccinated and protect themselves and their infants from RSV bronchiolitis this coming winter.”
Professor Damian Roland, from the Leicester Hospitals and University and a consultant in paediatric emergency medicine, said: “Our work highlights the value of vaccination and in keeping with the treatment to prevention principle of the NHS 10 Year plan, we would ask all health care systems to consider how they will optimise the rollout of RSV vaccination for mothers.”
The research team was led by the universities of Edinburgh and Leicester, and was funded by the Innovative Medicines Initiative, Respiratory Syncytial Virus Consortium in Europe, the Wellcome Trust, and National Institute for Health and Care Research at Imperial College London.
The study is published in the journal The Lancet Child and Adolescent Health.
