Respiratory syncytial virus (RSV) is a common respiratory virus that usually causes mild, cold-like symptoms. However, for some people, RSV can be very serious. Infants, young children and older adults are at increased risk of severe RSV. Starting this fall, vaccines are available to protect older adults and infants from severe RSV. In addition, monoclonal antibody products are available to protect infants and young children from severe RSV.
While RSV most often causes cold-like symptoms in infants and young children, it can also lead to serious lower respiratory tract infection (LRTI) such as pneumonia and bronchiolitis (swelling of the small airway passages in the lungs). The risk of RSV-associated LRTI is highest during a baby’s first year of life.
On August 21, 2023, the FDA approved a new vaccine (Abrysvo) for use in pregnant individuals to prevent LRTI and severe LRTI caused by RSV in infants from birth through 6 months of age.
On September 22, 2023, CDC’s expert advisory committee (ACIP) voted to recommend RSV vaccine for pregnant people at 32–36 weeks’ gestation using seasonal administration (meaning September–January in most of the United States) to prevent RSV-associated LRTI in infants aged <6 months. This recommendation was adopted by the CDC Director on September 22, 2023 and is now official. View the official recommendation published in MMWR.
On July 17, 2023, the FDA approved AstraZeneca’s Beyfortus (nirsevimab), a monoclonal antibody product, for the prevention of RSV in infants born during or entering their first RSV season, and in children up to 24 months of age who remain vulnerable to severe RSV disease through their second RSV season. To learn more, read the FDA’s full press release. On August 3, 2023, the CDC made the following recommendation for RSV Prevention in Infants:
- Infants aged <8 months born during or entering their first RSV season are recommended to receive one dose of nirsevimab (50 mg for infants <5 kg and 100 mg for infants ≥5 kg).
- Children aged 8–19 months who are at increased risk of severe RSV disease and entering their second RSV season are recommended to receive one dose of nirsevimab (200 mg).
The official ACIP recommendation for nirsevimab is now published in MMWR For more information on the prevention of RSV in infants and young children, visit CDC’s page for Healthcare Providers. Synagis (palivizumab) is a monoclonal antibody product recommended by the American Academy of Pediatrics (AAP) for administration to infants and young children who are at increased risk of severe RSV disease based on gestational age and certain underlying medical conditions. It is given in monthly intramuscular injections during RSV season.
On August 15, 2023, AAP published their recommendations for use of nirsevimab, along with considerations for the 2023–2024 RSV season with regard to palivizumab versus nirsevimab administration for high-risk infants during the same RSV season. View AAP’s news alert in AAP News and view AAP’s guidance in AAP’s Red Book Online.
On October 23, 2023, CDC released a health advisory notice to communicate interim recommendations regarding the limited supply of nirsevimab, the new preventive antibody to protect infants against severe RSV. Read more: Limited Availability of Nirsevimab in the United States—Interim CDC Recommendations
According to the CDC, adults at the highest risk for severe RSV illness include older adults, adults with chronic heart or lung disease, adults with weakened immune systems, and adults living in nursing homes or long-term care facilities. Every year, RSV causes approximately 60,000–160,000 hospitalizations and 6,000–10,000 deaths among older adults. There are now two FDA-approved RSV vaccines available for adults 60 and older – one from Pfizer and one from GSK. Click here for the RSV Vaccine Information Statement (VIS). In June 2023, the CDC recommended that adults 60 and older may receive a single dose of RSV vaccine, based on shared clinical decision-making. This means that these adults may receive a single dose of the RSV vaccine based on discussions with their healthcare provider about whether RSV vaccination is right for them.
RSV vaccine may be given at the same time as other vaccines like flu vaccine and COVID vaccine. Healthcare providers should be aware of underlying conditions that may increase the risk of severe RSV illness, and who might be most likely to benefit from these new vaccines. RSV vaccine is currently recommended as a single dose. Studies are ongoing to determine whether (and if so, when) revaccination may be needed. For more information on the prevention of RSV in adults, visit CDC’s page for Healthcare Providers.