The U.S. Centers for Disease Control and Prevention (CDC) has revised its criteria for who should get vaccinated against RSV (respiratory syncytial virus), a common virus that is generally harmless but that can cause serious and even life-threatening complications in the vulnerable.
On June 26, the federal health agency announced that for the upcoming fall virus virus, it strongly urges vaccination for people in two specific groups — those age 75 and older and those 60 to 74 who are at high risk of severe illness because of chronic health conditions.
That is a change from earlier guidelines, issued last fall, when the CDC advised that people age 60 and older have the option to receive the RSV vaccine, based on discussions with their healthcare provider.
In the June 26 announcement, the CDC director Mandy Cohen, MD, MPH stressed how important it is for adults living in nursing homes to get the RSV vaccine, as they are very susceptible to severe sickness.
The health agency also noted that people who have already received an RSV shot do not need another. The RSV vaccine is not an annual vaccine, meaning people don’t need it every virus season.
Why Did the CDC Revise Its Guidelines?
“It appears the CDC updated the recommendation to ensure those at highest risk for developing severe illness from RSV are being prioritized for vaccination,” says Krutika Kuppalli, MD, spokesperson for the Infectious Diseases Society of America and former medical officer at the World Health Organization.
The U.S. Food and Drug Administration (FDA) approved the first RSV vaccines more than a year ago, but only about 24 percent of adults 60 and over were vaccinated by spring 2024, according to the most recent CDC data.
Dr. Kuppalli anticipates that the more targeted criteria may help get protection to those who will benefit most.
“The initial recommendation was not clear about who should get the vaccine, so this may affect uptake,” says Kuppalli.
On the other hand, industry watchers note that the guideline change may reduce immunization rates overall by decreasing the number of eligible people.
RSV Vaccines Can Prevent Hospitalization and Death
RSV is a highly contagious virus that can cause symptoms in adults that usually are mild and cold-like symptoms, such as a runny nose, sore throat, cough and headache. But some people who don’t have strong defenses can feel absolutely miserable and potentially develop complications such as rapid breathing, fever, and pneumonia.
The federal government estimates that RSV leads to 60,000 to 160,000 hospitalizations annually among adults age 65 and up, and about 6,000 to 10,000 die each year from RSV-related lower respiratory tract disease.
The RSV vaccine may especially help older adults with chronic health conditions avoid some of the more dire outcomes. These illnesses include lung diseases such as chronic obstructive pulmonary disease (COPD) and asthma, and cardiovascular disease such as congestive heart failure and coronary artery disease.
What Are the Different RSV Vaccines?
Currently, there are three RSV vaccine options: Arexvy (from GSK), Abrysvo (from Pfizer), and mRESVIA (from Moderna). All are considered effective, although protection drops off over time.
The CDC notes that in a large late-stage clinical trial of Arexvy in people 60 years and older, a single dose of the vaccine reduced symptomatic RSV lower respiratory tract disease by over 82 percent during the first RSV season after vaccination compared to placebo, and by 56 percent during the second RSV season.
In a similar trial with Abrysvo, the CDC says, vaccination reduced RSV lower respiratory tract disease with three or more lower respiratory signs and symptoms by nearly 89 percent during the first RSV season after vaccination compared to placebo and dropped to about 79 percent during a partial second RSV season.
Moderna’s mRESVIA, a new RSV shot that was just approved by the FDA in May, had an efficacy against RSV lower respiratory tract disease of between 82 and 84 percent in the first season. In data presented on June 26, however, efficacy of the Moderna vaccine sunk to 50 percent after 18 months.
Currently the CDC is evaluating the risk of Guillain-Barré syndrome (GBS) in older adults following RSV vaccination. GBS is a rare nerve disorder that can occur after immunization; most people are able to make a full recovery.
