Preventing RSV

What is RSV?

Respiratory syncytial virus (RSV) typically causes mild, self-limiting (one to two weeks) cold-like symptoms.³

Serious RSV infections can cause respiratory distress, bronchiolitis, pneumonia, hospitalization, and death.^2,4

The typical season for RSV is from fall through late winter (i.e., October/November to March/April).^2,5

Who is at risk of severe RSV disease?

Those at risk of severe RSV disease include:

Infants and children less than two years.

Children with lung disease (e.g., congenital airway anomalies, chronic lung disease of prematurity, cystic fibrosis), congenital heart disease, neuromuscular disorders, Down syndrome, immunosuppressive disorders, and some infants in remote communities (e.g., American Indian, Alaska Native children).^2,4,6-8

Older adults and patients with chronic lung disease, heart disease, or immunosuppressive disorders.²

How can RSV be prevented?

RSV is transmitted via respiratory droplets (inhaled and from contact with contaminated surfaces).^5,9

• Prevent transmission of RSV (and other respiratory illnesses) by:⁹
  • coughing or sneezing into a tissue or your shirt sleeve/elbow (not your hands).
  • washing hands with soap and water for at least 20 seconds.
  • avoiding close contact with people (i.e., stay at home) when you feel ill (i.e., cold-like symptoms).
  • cleaning frequently touched surfaces (e.g., doorknobs, mobile devices).

• Monoclonal antibody formulations (nirsevimab, palivizumab) are available to prevent RSV in infants and young children (see below for details).

  • provide passive immunization.
  • protection wanes over time.
  • must be administered in a clinic or hospital.

RSV vaccines are available for pregnant patients and older adults (see below for more details).

Infants can be protected with either maternal immunization OR monoclonal antibodies (see sections below for preferred choices). Most infants do not need both.²¹

Who should get the monoclonal antibody, nirsevimab (Beyfortus)?

Nirsevimab is FDA- and Health Canada-indicated for the prevention of RSV infection in:^6,11

US recommendations: ACIP recommends nirsevimab for infants <8 months born during or entering their first RSV season and children aged 8 to 19 months who are at increased risk of severe RSV disease entering their second RSV season.^5,c

Canadian recommendations: NACI recommends nirsevimab for infants, prioritized as follows:¹⁹

• Priority 1:
  • Infants born during or entering their first RSV season who are at increased risk of severe RSV disease.^d
  • Infants entering their second RSV season who are at continued increased risk of severe RSV disease.^e
• Priority 2:
  • Consider for any infant less than 8 months of age born during or entering their first RSV season.

Who should get the monoclonal antibody, palivizumab (Synagis)?

Palivizumab is indicated for the prevention of RSV infection in high-risk infants and toddlers.^9,10,12

Nirsevimab is preferred over palivizumab for the prevention of RSV infection.¹⁹

If nirsevimab is not available or not feasible to administer, palivizumab can be administered to high-risk patients (see guidelines for specific high-risk indications for palivizumab use).^5,19 

• For example, the American Academy of Pediatrics recommends palivizumab (if nirsevimab is not available) for:^4,12
  • infants born before 29 weeks gestation and who are younger than 12 months at the beginning of the RSV season.
  • infants under one year of age with chronic lung disease of prematurity. During the second year of life, palivizumab can be considered if these children have continued to require medical support during the six months prior to RSV season.
  • palivizumab can also be considered for patients:^4,12
    • younger than 24 months who are profoundly immunocompromised during the RSV season.
    • younger than 12 months:
      • with a pulmonary or neurological abnormality that impairs clearance of upper airway secretions.
      • who have hemodynamically significant congenital heart disease.

Can monoclonal antibodies be given with vaccines?

Nirsevimab can be given at the same time as routine childhood vaccines.⁵

How do the available RSV monoclonal antibodies compare?

Palivizumab (Synagis)^9,10

Nirsevimab (Beyfortus)^6,11

How Supplied

Single-dose vials:

50 mg/0.5 mL, 100 mg/1 mL

Single-dose prefilled syringes:

50 mg/0.5 mL, 100 mg/1 mL

Storage

Refrigerate (2°C to 8°C).

Opened vials may be kept (refrigerated) for up to
6 hours.²⁵

Store in original packaging.

Do not shake.

Refrigerate (2°C to 8°C).

May be kept at room temperature (20°C to 25°C) for up to 8 hours.

Store in original packaging to protect from light.

Do not shake.

Dosing

15 mg/kg IM monthly throughout the RSV season.

Give an additional dose to children following cardiopulmonary bypass surgery (even if less than one month since last dose).^7,9

It is recommended to stop monthly palivizumab if a child has an RSV hospitalization.^7,12

Usual duration is four to five months.^7,9

First RSV season:

Second RSV season:

Give an additional dose to children following cardiopulmonary bypass surgery. See footnote “b” for dosing.

Adverse Effects

Rash, fever, severe hypersensitivity reactions

Rash, injection site reactions.

Potential for serious hypersensitivity reactions.

Usual Admin Site

Anterolateral thigh preferred.

Avoid the gluteal muscle.

Anterolateral thigh preferred.

Avoid the gluteal muscle.

Cost (US)^a

~$1,800/50 mg

$520/50 mg or 100 mg syringe

Who should get an RSV vaccine?

A single dose of RSV vaccine is recommended for all adults 75 years and older (especially those at increased risk of severe RSV disease [Canada]).^16,28

For adults 60 to 74 years, RSV vaccine is recommended for:

• ACIP (US): patients who are at increased risk of severe RSV disease.¹⁶
• NACI (Canada): residents of chronic care facilities and nursing homes. Can also consider for patients based on individual decisions in consultation with healthcare providers.²⁸

In addition, the RSV vaccine Abrysvo is recommended for:

• Pregnant patients (32 weeks through 36 weeks gestation) to prevent RSV disease in newborns:
  • ACIP (US) recommends Abrysvo for seasonal use (usually September through January).²¹ One lifetime dose is currently recommended (i.e., repeat dosing with subsequent pregnancies is not recommended due to lack of data).²⁰
  • NACI (Canada) recommends shared decision making (taking into account gestational timing and RSV season) rather than routine vaccination.¹⁹

How do the available RSV vaccines compare?

Abrysvo^13,24

Arexvy^17,18

mRESVIA (US only)²³

Vaccine type

non-adjuvanted

adjuvanted (with AS01_E)

mRNA

Approved indications

for the prevention of RSV in:

for the prevention of RSV in patients:

for the prevention of RSV in patients 60 years and older.

Dosing

0.5 mL IM x one dose

0.5 mL IM x one dose

0.5 mL IM x one dose

Use in pregnant patients

There is a potential risk of preterm birth with Abrysvo. To avoid this risk, do not administer Abrysvo prior to 32 weeks gestation. Patients at risk of preterm birth were generally excluded from the studies.

There are no data on the administration of Arexvy in pregnant patients.

There are no data on the administration of mRESVIA in pregnant patients.

Storage

Refrigerate (2°C to 8°C) in the original packaging.

Refrigerate (2°C to 8°C) in the original packaging to protect from light.

Store frozen (-40°C to -15°C).

After thawing, can be refrigerated (2°C to 8°C) for up to 30 days OR stored at room temperature (8°C to 25°C) for up to 24 hours.

Do not return to fridge once at room temperature.

Do not refreeze.

Reconstitution and stability

Reconstitute with the diluent provided. Use immediately or keep at room temperature (15°C to 30°C) and use within four hours.

Reconstitute with the diluent provided. Use immediately or refrigerate (2°C to 8°C) and use within four hours.

Thaw in fridge (2°C to 8°C) for
60 minutes (155 minutes for larger 10-syringe carton). Prior to admin, let sit at room temperature for 10 to 20 minutes.

OR

Thaw at room temperature
(15°C to 25°C) for 45 minutes (140 minutes for 10-syringe carton).

Abrysvo^13,24

Arexvy^17,18

mRESVIA (US only)²³

Efficacy

Data show moderate to high efficacy of one dose of Abrysvo in older adults for the prevention of RSV-associated symptomatic LRTD and medically attended LRTD over two RSV seasons [Evidence Level A-1].¹⁴

CDC data from RSV vaccine use during the 2023-2024 season showed reduced hospitalization, critical illness (ICU admission, death), and ED visits in patients 60 years and older.²⁹

Infants born to pregnant patients who were given Abrysvo, had a significantly reduced risk of severe LRTD at both 90 days and 180 days after birth [Evidence Level A-1].¹⁵

Data show moderate to high efficacy of one dose of Arexvy in older adults for the prevention of RSV-associated symptomatic LRTD and medically attended LRTD over two RSV seasons [Evidence Level A-1].¹⁴

CDC data from RSV vaccine use during the 2023-2024 season showed reduced hospitalization, critical illness (ICU admission, death), and ED visits in patients 60 years and older.²⁹

Data show moderate to high efficacy of one dose of mRESVIA in older adults for the prevention of RSV-associated symptomatic LRTD over a median follow-up of 3.7 months (first interim analysis; follow-up is ongoing) [Evidence Level A-1].^26,27

Cost^a

Per dose:

Per dose:

Per dose: