Respiratory Syncytial Virus (RSV)

Advisory Committee on Immunization Practices (ACIP) Recommendations

Adults

• Adults at least 60 years of age may receive a single dose of Respiratory Syncytial Virus (RSV) vaccine, based on shared clinical decision making.

For More Information

• ACIP Recommendations: https://www.cdc.gov/vaccines/hcp/acip-recs/vacc-specific/rsv.html
• Immunization schedules: http://www.cdc.gov/vaccines/schedules/index.html 

Important Information for Obstetric Providers

• RSV vaccines are not routinely recommended during pregnancy.

Disease

Respiratory syncytial virus (RSV) is an RNA virus of the genus Orthopneumovirus. There are two main types of human RSV (Type A and Type B). Most subtypes are determined by antigenic drift and duplications in RSV-G sequences, but may also have genome-wide sequence divergence. This makes RSV relatively adept at evading immunity induced by prior infection or vaccination ¹.

RSV is a common cause of lower respiratory tract disease (LRTD), with symptoms such as runny nose, coughing, sneezing, wheezing, fever, and decreased appetite. Although RSV is usually mild, it can cause severe illness, including pneumonia and bronchiolitis, and may also lead to worsening of existing conditions, such as asthma, chronic obstructive pulmonary disease (COPD), and congestive heart failure. Symptoms typically appear within 4-6 days after infection, and infected persons may become contagious a day or two before showing any symptoms. RSV spreads through droplets from coughing and sneezing, but also can survive for hours on hard surfaces and spread by touching one’s face after touching a contaminated surface.

Premature infants, young children with congenital heart or chronic lung disease, children with neuromuscular disorders, persons with compromised immune systems, and older adults (especially those with pre-existing heart or lung disease) are at the highest risk for severe disease. Every year in the US, RSV is estimated to cause 58,000-80,000 hospitalizations and 100–300 deaths among children less than 5 years old, and 60,000-160,000 hospitalizations and 6,000-10,000 deaths among adults 65 years and older ².

Vaccine

Two RSV vaccines are licensed for use among adults at least 60 years of age in the United States: RSVPreF3 (Arexvy) and RSVpreF (Abrysvo™). Both vaccines contain 120µg of antigen and are administered as a single 0.5mL dose via intramuscular injection. RSVPreF3 includes an AS01 adjuvant, and RSVpreF is bivalent ^3,4.

Contraindications and Precautions

Severe allergic reaction (e.g. anaphylaxis) to a previous dose or vaccine component is a contraindication to further vaccination with RSV vaccines^3,4. Current moderate to severe acute illness is a precaution to any vaccination ⁵.

Vaccine Effectiveness

Clinical trials found RSVPreF3 to be 83% effective against RSV-associated LRTD and 94% effective against severe RSV-associated LRTD among adults at least 60 years of age ⁶. Clinical trials found RSVpreF to be 62% effective against RSV-associated acute respiratory illness, 67% effective against RSV-associated LRTD with at least two symptoms, and 86% effective against RSV-associated LRTD with at least three symptoms, among adults at least 60 years of age ⁷.

Vaccine Safety

The most commonly reported side effects among RSVPreF3 vaccine recipients in the clinical trial were injection site pain (61%), fatigue (34%), myalgia (29%), headache (27%), and arthralgia (18%). Additionally, 10 RSVPreF3 vaccine recipients in the clinical trial experienced atrial fibrillation within 30 days of vaccination, compared to 4 placebo recipients ^4,6.

Local reactions occurred in 12% of RSVPreF vaccine recipients (compared to 7% of placebo recipients). Most local reactions were mild to moderate and transient. The most common local reaction experienced was injection site pain (11%). Systemic events (such as fatigue, headache, and fever) occurred in similar amounts among vaccine and placebo recipients ^3,7.

Considerations in Pregnancy

RSV vaccines are not currently licensed for pregnant women. However, RSV vaccines may be licensed for pregnant women in the near future.

References

1.         World Health Organization. Respiratory Syncytial Virus (RSV) disease. (https://www.who.int/teams/health-product-policy-and-standards/standards-and-specifications/vaccine-standardization/respiratory-syncytial-virus-disease).

2.         Centers for Disease Control and Prevention. Respiratory Syncytial Virus Infection (RSV). October 28, 2022 (https://www.cdc.gov/rsv/index.html).

3.         Food and Drug Administration. Package Insert – ABRYSVO. (https://www.fda.gov/media/168889/download).

4.         Food and Drug Administration. Package Insert – AREXVY. (https://www.fda.gov/media/167805/download).

5.         Epidemiology and Prevention of Vaccine-Preventable Diseases. Washington D.C.: Centers for Disease Control and Prevention, 2015.

6.         Food and Drug Administration. FDA Approves First Respiratory Syncytial Virus (RSV) Vaccine. 2023.

7.         Walsh EE, Pérez Marc G, Zareba AM, et al. Efficacy and Safety of a Bivalent RSV Prefusion F Vaccine in Older Adults. The New England journal of medicine 2023;388(16):1465-1477. (In eng). DOI: 10.1056/NEJMoa2213836.