RSV vaccines prove highly effective worldwide: now the challenge is reaching everyone

The findings—led by researchers at the University of Edinburgh and Imperial College London and published in EClinicalMedicine and Thorax—show that recently introduced RSV vaccines and antibody treatments are both safe and highly effective in preventing severe illness in infants and older adults. However, uptake remains uneven, with large gaps between countries and population groups.

RSV is one of the world’s leading causes of acute respiratory infections, and is particularly dangerous for babies and older adults. Globally, RSV causes around 33 million lower respiratory infections in children under five each year, leading to over 3.6 million hospitalisations and more than 100,000 deaths.

For decades, there was no widely available vaccine. However, over the last two years, several new products have become available:

• Nirsevimab, a long-acting monoclonal antibody for infants
• The RSV maternal vaccine (given during pregnancy to protect newborns)
• Three RSV vaccines for adults aged 60 and over
  
   

Study 1

The first study, published in EClinicalMedicine, analysed 43 studies covering 1.38 million people across six countries (Spain, United States, France, Andorra, Italy and Luxembourg) to measure real-world uptake of these new RSV immunisations.

It found that Spain led the way in RSV immunisations, with 90% of eligible infants receiving nirsevimab during the 2023/24 RSV season. In contrast, uptake in the United States was just over 50%.

For adults, coverage was much lower. Only 30% of pregnant people received the maternal vaccine, and 18% of older adults had been vaccinated against RSV in the United States. Overall, the study highlighted clear inequalities: uptake was lower among ethnic minority groups, lower-income households, and people without public health insurance.

Lead author Daira Trusinska from the University of Edinburgh said: 

“National, clinical, and public health efforts are needed to encourage RSV immunisation and protect people most at risk of serious illness.”

Study 2

The second paper, published in Thorax, examined real-world effectiveness and safety across 7.6 million people from 50 studies.

The research team found that Nirsevimab reduced RSV-related hospital admissions in infants by 81% and intensive care admissions by 76%. Moreover, RSV vaccines for older adults cut hospitalisations by about 80%, with fewer than 10 Guillain–Barré syndrome cases per million doses. Finally, the RSV maternal vaccine appeared safe, with no link to preterm birth or other serious pregnancy complications. However, effectiveness data are still emerging.

Joint first author Dr Bohee Lee from Imperial College London said:

“It’s reassuring to see that concerns about safety should not discourage vaccine uptake across different age groups. While continued monitoring is essential, the data so far are very encouraging.”

Although these results appear encouraging, the study authors caution that the success of RSV prevention depends on public health systems translating clinical promise into real coverage.

Senior author Dr Ting Shi, from the University of Edinburgh, said:

“The real world evidence has shown that newly approved RSV vaccines for both pregnant women and older adults offer valuable protection against severe respiratory illness in infants and older adults — an important step forward in reducing the seasonal burden of RSV across the population.”

Taken together, the studies emphasise that while the clinical promise of RSV prevention is being realised, global immunisation programmes must focus on coverage, confidence, and equity.

Full citations:

Trusinska, D., Lee, B., Ferdous, S., Kwok, H. H. Y., Gordon, B., Gao, J., Ma, L., Xiong, H., Sheikh, S. A., Schwarze, J., Busby, J., Gibbons, C., Drysdale, S. B., Ritchie, S. L., Williams, T., & Shi, T. (2025). Real-world uptake of nirsevimab, RSV maternal vaccine, and RSV vaccines for older adults: a systematic review and meta-analysis. EClinicalMedicine, 84, 103281. https://doi.org/10.1016/j.eclinm.2025.103281

Lee, B., Trusinska, D., Ferdous, S., Pei, R., Kwok, H. H. Y., Schwarze, J., Williams, T. C., Gibbons, C., Quint, J. K., Sheikh, A., Drysdale, S. B., & Shi, T. (2025). Real-world effectiveness and safety of nirsevimab, RSV maternal vaccine and RSV vaccines for older adults: a living systematic review and meta-analysis. Thorax, 80(11), 838–848. https://doi.org/10.1136/thorax-2025-223376