A recent Cochrane review shows that vaccines for the respiratory syncytial virus (RSV) are both safe and effective in protecting the groups most at risk of severe disease, such as older adults and infants.
RSV is a common culprit behind coughs and colds, but it can also cause life‑threatening lung infections, including pneumonia. Children younger than two years, and older adults, are especially vulnerable to severe RSV outcomes.
Researchers from multiple countries examined 14 randomized trials that included more than 100,000 participants—spanning older adults, pregnant women, women of child‑bearing age, and children. The studies were carried out on every continent and were published in the Cochrane Database of Systematic Reviews.
The data revealed that RSV prefusion vaccines reduce lower‑respiratory‑tract disease (such as pneumonia and bronchitis) in older adults by 77 % and acute respiratory disease (like a common cold) by 67 %. When pregnant individuals received an RSV F‑protein‑based vaccine, their infants saw a 54 % decline in medical care for RSV lower‑respiratory‑tract disease, a 74 % reduction in severe RSV disease, and a 54 % lower chance of hospitalization.
"From our review of clinical trials, we found high‑certainty evidence that RSV vaccines protect older adults and strong evidence they benefit infants when mothers are vaccinated during pregnancy," said Dr. KM Saif‑Ur‑Rahman, lead author and Senior Research Methodologist at Evidence Synthesis Ireland and Cochrane Ireland, University of Galway, Ireland. "That’s encouraging news for two of the groups most at risk."
There was little to no difference in serious side effects between those who received the vaccine and those who did not, across all age groups.
These findings are based solely on randomized‑trial data, as real‑world evidence on effectiveness and safety had not yet become available at the time of publication.
"It’s important to stress that our review comes from randomized trials, the strongest evidence we have," said Kate Olsson, author and vaccine expert at the European Centre for Disease Prevention and Control (ECDC). "Post‑authorization real‑world studies are underway, and their data will continue to add to our understanding of RSV vaccine safety and efficacy."
The systematic review will be updated with two further analyses on the efficacy, effectiveness, and safety of different RSV vaccines. ECDC plans to release the first updated review with new data in the coming weeks.