Oct. 18, 2024 – Older people who aren’t sure about whether to get the vaccine for respiratory syncytial virus (RSV) now have a new set of data to help them make up their minds.
A large study in The Lancet concluded the vaccine is 80% effective at preventing hospitalization due to complications from the illness, and similarly effective at protecting older people from death or needing care for severe complications in the hospital’s intensive care unit. The vaccines were nearly as effective at preventing RSV-related visits to the emergency room.
When the researchers only looked at data for immunocompromised people, vaccination was 73% effective at preventing hospitalization. The team used data from CDC scientists, university and hospital researchers, and also included work by employees of nonprofit and private sector firms. They determined effectiveness based on comparing vaccinated people to unvaccinated people who all had similar symptoms and were tested for the virus.
The report is the largest study to date looking at first-year data on how well the shots work in the real world. The vaccines were first approved in the U.S. last May, and medical and public health officials have been eager to see how well the vaccines worked outside of clinical trials, which had suggested that the shots may be more than 90% effective at preventing severe illness.
“No vaccine is 100 percent effective. An 80 percent vaccine effectiveness rate is quite impressive and higher than we see, for example, with the influenza vaccine,” study co-author and Indiana University professor Brian Dixon, PhD, MPA, said in a statement.
“The bottom line,” Dixon continued, “is that using real world data from electronic medical records routinely captured in care for people from diverse walks of life we found that having the vaccine was highly protective against hospitalization, severe illness and death.”
The study included data for 36,706 people ages 60 and older in eight states, spanning 230 hospitals in California, Colorado, Indiana, Minnesota, Oregon, Utah, Washington, and Wisconsin. All of the people in the study took an RSV test between Oct. 1, 2023, and March 31, 2024, and 1,926 people tested positive. There were 3,275 vaccinated people in the study, as determined by electronic health records, city or state immunization registries, or medical claims.
In most people, RSV causes common cold symptoms like nasal congestion, a runny nose, low-grade fever, and sore throat. But older people have a higher risk of severe illness when the infection spreads to the lower respiratory tract and causes pneumonia or another condition called bronchiolitis that makes breathing difficult due to inflammation in the small airway passages to the lungs.
RSV vaccines for older adults are available from two drugmakers, and the CDC doesn’t recommend one over the other. Pfizer makes Abrysvo, and GSK makes Arexvy. The researchers in this latest study reported that effectiveness was similar for both shots.
The CDC currently recommends that everyone ages 75 and older get at least one dose, and adults ages 60 to 74 should get a dose if they have a higher risk of severe RSV, such as having chronic heart problems, a chronic lung or respiratory disease, severe obesity, certain diabetes conditions, or if they live in a nursing home. People don’t need to get a new dose each year.
This year, the CDC scaled back its initial recommendation for people 60 to 74 years old, saying that only people in that age group should get vaccinated if they had increased risk.
As of Oct. 5, the CDC reported that 37% of people 75 and older say they have ever received an RSV vaccine, and 13% said they will definitely get one. Among adults 60 to 74 years old, 24% said they’d been vaccinated for RSV, and 10% said they definitely will get the shot.
Cases of RSV nationwide remain low. Last year, activity increased in November and peaked around the new year.
