Maternal RSV vaccine prevents hundreds of infant hospitalisations in first real-world national study

The study was led by researchers from Public Health Scotland and a multidisciplinary team including Professor Sir Aziz Sheikh, Head of the Nuffield Department of Primary Care Health Sciences, along with colleagues from the Universities of Glasgow, Strathclyde and Edinburgh. 

Published in The Lancet Infectious Diseases, the study is the first to evaluate maternal RSV vaccination across an entire national population using real-world data.  

RSV: a common virus that can become life-threatening for babies 

Respiratory syncytial virus, or RSV, is an incredibly common illness one of the leading causes of infant hospitalisation worldwide. While most infections resemble a bad cold, RSV can cause severe breathing and feeding difficulties in very young babies, particularly those under six months old and those born prematurely.  

In Scotland, hundreds of babies are admitted to hospital with RSV each winter. Ahead of the 2024/25 season, Scotland became one of the first countries in the world to introduce routine maternal RSV vaccination, offering the vaccine to pregnant women from 28 weeks gestation so they can pass protective antibodies to their babies before birth. 

What the study found 

Using routinely collected health data, the researchers examined outcomes for all 27,552 infants born in Scotland between August 2024 and March 2025. Half of all pregnant women during this period were vaccinated. 

Key findings include: 

• Babies whose mothers received the RSV vaccine at least 14 days before delivery had an 82.9% lower chance of being hospitalised with RSV-related lower respiratory tract infections. 

• The vaccine was also highly effective for preterm infants, reducing hospitalisations by 89%. 

• Overall, the programme prevented an estimated 228 infant hospitalisations during the study period. 

The study also showed that babies whose mothers were vaccinated less than two weeks before birth did not receive the same level of protection. This is because it takes time for the mother to produce protective antibodies after vaccination, and for these to be passed on to the baby. The study found that infants born less than 14 days after their mother received the vaccine did not receive meaningful protection, highlighting the importance of getting vaccinated as soon after 28 weeks of pregnancy as possible. 

A major step forward for infant health 

Professor Sir Aziz Sheikh, Head of the Nuffield Department of Primary Care Health Sciences, University of Oxford, and an author of the study said: 

‘These results show, on a national scale and using real-world data, that maternal RSV vaccination is making a substantial difference to the health of young babies. In its first season alone, the programme prevented hundreds of hospital admissions, sparing families significant distress and reducing winter pressures on the NHS. This is compelling evidence that rolling out maternal RSV vaccination globally could save many lives.’ 

Public Health Scotland welcomed the findings as an important milestone for infant health. 

Dr Ross McQueenie, Lead Healthcare Scientist – Vaccine Effectiveness and Respiratory Inequalities, Public Health Scotland, said:  

‘The early success of the maternal RSV vaccine illustrates the preventative value of public health immunisation programmes. This vaccination, like so many others, stops serious illness and improves the health of children and communities.’