RSV Immunization Recommendations for 2024

Respiratory syncytial virus (RSV) can be dangerous for babies and older adults. As we approach another RSV season, immunizations are available to protect people in these groups from severe RSV. There is one set of recommendations for older adults, and a separate set — which includes two immunization options — to protect babies. As we approach RSV season, here is what healthcare providers can do this year to protect patients against severe RSV. 

1. RSV is most commonly associated with illness in infants. Why is it important that eligible older adults get a vaccine?

RSV can be dangerous for older adults, especially those age 60 or older who are at increased risk for severe RSV. RSV can cause bronchiolitis and pneumonia, and can make chronic health problems worse. CDC estimates that every year in the United States, 100,000-160,000 older adults are hospitalized with RSV.^[1]

RSV vaccines, introduced last year, give us a powerful tool to protect older adults against RSV.

2. As we approach another RSV season, which older adults are eligible for an RSV vaccine?

CDC recommends RSV vaccines for everyone age 75 or older and for adults age 60-74 who are at increased risk for severe RSV. Adults age 60-74 are considered at increased risk if they have one or more of the following risk factors:

• Chronic heart or lung disease
• A weakened immune system
• Certain other medical conditions*, including diabetes with complications and severe obesity 
• Live in a nursing home 

*For a complete list of chronic health issues that lead to increased risk for severe RSV, see Clinical Overview of RSV.

The RSV vaccine for older adults is not currently an annual vaccine. Patients who have already received an RSV vaccine do not need another dose at this time.

The best time for older adults to get vaccinated is now, before the RSV season starts! 

3. In June 2024, there was a shift in the recommendation from using shared clinical decision-making to a risk-based recommendation for adults age 60-74, and a universal recommendation for all adults age 75 or older. Why is that?

CDC and the Advisory Committee on Immunization Practices (ACIP) regularly evaluate new information as it becomes available to inform vaccine recommendations.

These updated recommendations clarify who is at highest risk for severe illness. They take into account data on vaccine effectiveness and vaccine safety, and also address feedback from healthcare providers about difficulties implementing RSV vaccines under the previous recommendation. 

4. How effective are RSV vaccines at protecting older adults?

Real-world data gathered during the 2023-2024 RSV season show that RSV vaccines reduced the risk for RSV-associated hospitalization or emergency department visits by 75%-80%.^[2,3] Of note, these data include populations that are at highest risk for severe RSV, including those age 75 or older, those who are immunocompromised, and those who live in nursing homes.

5. In regard to protecting infants from RSV (which continues to be the leading cause of infant hospitalization), last year was also the first year that RSV immunizations became available to protect infants. Are there any changes to those recommendations?

There are no changes to CDC’s recommendations for infant immunizations this year. CDC continues to recommend that all infants receive protection from severe RSV by one of two immunization options: 

• A maternal RSV vaccine (Abrysvo) given to the mother during weeks 32-36 of pregnancy
• An RSV antibody (nirsevimab) given to the baby after birth, ideally during the birth hospitalization if born October through March. 

Most babies will not need both. 

Nirsevimab is also recommended for a smaller group of young children 8-19 months of age who are at increased risk for severe RSV.

Healthcare providers should talk with their patients about both immunizations and consider patient preferences when deciding which product is best for their family.

6. When should maternal vaccines or nirsevimab be administered?

RSV maternal vaccine (Abrysvo) and RSV antibody (nirsevimab) are each recommended during specific times of the year to maximize their benefit. In most of the continental United States, the maternal vaccine should be given September-January, while nirsevimab should be given October-March. 

For infants born during this window (ie, October-March), the optimal timing for nirsevimab administration is within the infant’s first week of life, ideally during the birth hospitalization.

For infants born outside of this window (ie, April – September) and for young children who are at increased risk for severe RSV disease and entering their second RSV season, the optimal timing for nirsevimab administration is shortly before the RSV season begins (October or November). 

CDC does not currently recommend maternal vaccination outside of the seasonal administration window (ie, September-January) in most of the continental United States^†. Instead, the baby would be better protected by receiving nirsevimab in October or November.

Because the timing of the onset, peak, and decline of RSV activity varies geographically, public health authorities (eg, CDC, health departments) or regional medical centers may provide additional guidance for nirsevimab administration for their jurisdictions. Additionally, special circumstances may also need to be considered, such as travel to areas with increased RSV activity or concerns that the infant or child may not return for a visit when nirsevimab should ideally be administered. 

^† In jurisdictions with RSV seasonality that differs from most of the continental United States, including Alaska, southern Florida, Guam, Hawaii, Puerto Rico, US-affiliated Pacific Islands, and US Virgin Islands, healthcare providers should follow state, local, or territorial guidance on timing of maternal RSV vaccination.

Maternal RSV vaccination should be limited to within the seasonal administration window, but the recommendation on the timing of nirsevimab administration is intentionally flexible to help optimize patient access. 

7. How well do these immunizations protect babies from severe RSV?

Clinical trial data show that nirsevimab provided protection against RSV that lasted at least 5 months.^[4] Initial real-world data show that nirsevimab was 80%-90% effective in the first months after immunization in preventing babies from being hospitalized with RSV.^[5,6] 

CDC continues to gather real-world effectiveness data for maternal RSV vaccine (Abrysvo). The best data at this time are from the phase 3 clinical trial, which showed that the maternal RSV vaccine reduced the risk of the baby being hospitalized for RSV by 68% and the risk of having a healthcare visit for RSV by 57% within 3 months after birth.^[7] Additional data show that maternal antibodies protect the baby against RSV for approximately 6 months after birth.^[7] 

The protection that babies receive from each of these immunization options wanes over time, but it is important to emphasize that both options give babies protection from severe RSV when they are most susceptible to severe outcomes. 

8. What should healthcare providers do to help protect their patients during this upcoming RSV season?

A healthcare provider’s recommendation is one of the most important factors in a person’s decision to get immunized. For your eligible patients, make a strong recommendation for these immunizations; it may be the reason they choose to get protected or protect their baby.

Remember, now is the best time for us to be giving RSV immunizations to eligible patients so that they can be protected throughout the entire RSV season. 

Still have questions? CDC’s website provides comprehensive guidance for each of these immunization recommendations. 

Resources

Respiratory Syncytial Virus (RSV) | RSV | CDC

Clinical Overview of RSV | RSV | CDC

Clinical Guidance for RSV Immunizations and Vaccines | RSV | CDC