A new Cochrane review demonstrates that respiratory syncytial virus (RSV) vaccines are safe and effective in protecting vulnerable groups most at risk of serious illness, including older adults and infants.
The review was based on 14 clinical trials with more than 100,000 participants. The studies did not report RSV‐related hospitalization or intensive care unit (ICU) admission.
Overall, studies showed vaccines were 77% effective against both RSV-associated lower respiratory tract disease (pneumonia and bronchitis), and 67% effective in protecting against RSV-associated acute respiratory disease (common cold) in older adults.
Studies of vaccination in pregnant women showed RSV F protein-based vaccines reduced the risk of their children needing medical care for RSV-associated lower respiratory tract disease by 54%, reduced the babies’ chance of severe RSV-related disease by 74%, and lowered the risk of hospitalization by 54%.
We found high-certainty evidence that RSV vaccines protect older adults and strong evidence they benefit infants when mothers are vaccinated during pregnancy
“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 KM Saif-Ur-Rahman, PhD, the lead author and senior research methodologist at Evidence Synthesis Ireland and Cochrane Ireland, in a press release. “That is encouraging news for two of the groups most at risk.”
Little evidence of side effects
For studies in older adults and pregnant women, there was little evidence that vaccinated groups had more adverse events than control groups.
In total, the review included five studies on older adults, three on the effect of vaccinating pregnant women on their babies, one on women of childbearing age, and five on infants and children.
Data on the efficacy of RSV vaccines on women of childbearing age and on infants and children were more limited and produced reports of low confidence.
“We are uncertain if live RSV vaccines reduce respiratory illnesses and RSV‐related illnesses in infants and children,” the authors of the review wrote.
The evidence was very uncertain regarding all‐cause medically attended acute respiratory illness with vaccine efficacy (VE) of 26% (95% confidence interval [CI], −0.01 to 0.46). Among women of childbearing age, the evidence was very uncertain regarding new RSV infections with VE of 50% (95% CI, 0.08 to 0.73).
“It’s important to be clear that our review is based on evidence from randomised trials, the strongest evidence available,” said Kate Olsson, MPH, a study author from the European Centre for Disease Prevention and Control in a press release. “Post authorisation, real-world studies are ongoing and data from those studies will continue to add to what we know about the safety and effectiveness of these RSV vaccines.”