Centers for Disease Control and Prevention

Respiratory Syncytial Virus (RSV) 

Immunization Recommendations 

to Protect Infants and Children 

Slide Deck

Audience: Healthcare Professionals 

who Provide Care to Pregnant Patients
RSV is a leading cause of hospitalization in US infants

 About 2-3% of young infants will be 

hospitalized for RSV

 About 58,000-80,000 US children 

aged <5 years are hospitalized with 

RSV each year

 RSV-associated hospitalization highest 

in infants aged <3 months and then 

decreases with increasing age

 Preterm infants experience higher 

hospitalization and ICU rates

Hall et al. (2013); Langley & Anderson (2011); CDC NVSN data
FDA approved and CDC recommends two ways to 

protect infants from severe RSV disease

RSV vaccine 

given during 

pregnancy RSV 

antibody 

given to 

the infant
Abrysvo (Pfizer) is the ONLY RSV 

vaccine approved for pregnant people

 CDC recommends maternal RSV vaccination during 

32 weeks + 0 days through 36 weeks + 6 days

gestation, with seasonal administration

– During September through January in most of the 

continental United States

– According to local guidance in jurisdictions where 

seasonality differs from most of the continental US

 Abrysvo (Pfizer) RSV vaccine can be simultaneously 

administered with other indicated vaccinations
Maternal Abrysvo (Pfizer) RSV vaccine is efficacious

against severe RSV disease in infants up to 6 months

 Abrysvo (Pfizer) RSV vaccine: Phase 2b and 3 trials (included >7500 people)

– Full trial dosing interval included administration 24–36 weeks gestation

– Additional analyses conducted during approved dosing interval (32–36 weeks)

Vaccine efficacy estimates (through 180 days of life):

Severe medically attended RSVassociated lower respiratory tract 

infections (LTRI):

69.4% (97.58% CI = 44.3%–84.1%) when 

vaccinated during full trial dosing interval 

(24-36 weeks)NEJM.

Hospitalization for RSVassociated LRTI:

56.8% (99.17% CI = 10.1%–80.7%) when 

vaccinated during full trial dosing interval 

(24-36 weeks)

Fleming-Dutra KE, Jones JM, Roper LE, et al: https://www.cdc.gov/mmwr/volumes/72/wr/mm7241e1.htm
Benefits of maternal vaccination with Abrysvo (Pfizer) 

RSV vaccine outweigh potential risks

 Most common side effects: pain at injection site, headache, myalgia, nausea

What did clinical trial data show about 

risks during pregnancy?

More preterm births and reports of 

hypertension during pregnancy were 

observed among those who received vaccine 

during weeks 24-36 gestation versus placebo. 

The imbalance was not statistically significant. 

How do we interpret this?

• Available data are insufficient to establish 

or exclude a causal relationship between 

these outcomes and Abrysvo. 

• To reduce the potential risk of preterm birth, 

vaccine was approved for use during weeks 

32 through 36 of pregnancy.

Fleming-Dutra KE, Jones JM, Roper LE, et al: https://www.cdc.gov/mmwr/volumes/72/wr/mm7241e1.htm
Monitoring safety and effectiveness of maternal RSV 

vaccine will continue

 Pfizer’s pregnancy registry: Individuals who received Abrysvo during 

pregnancy are encouraged to contact, or have their healthcare provider 

contact, 1-800-616-3791 to enroll in or get information about the registry.

 Vaccine Adverse Event Reporting System (VAERS): Advise vaccine recipient 

to report any adverse events to their healthcare provider or to the VAERS at 

1-800-822-7967 and www.vaers.hhs.gov.

 V-safe: Encourage pregnant individuals to register for v-safe, a digital 

platform that conducts health check-ins following RSV vaccination.
Promote V-safe – we need your help!

Materials are available to share information 

about V-safe

• Information sheets

• Social media posts

• Communications to vaccine recipients

Materials and more information available at:

https://www.cdc.gov/vaccinesafety/ensuringsafety/monitoring/v-safe/index.html
Nirsevimab (Sanofi and AstraZeneca) is 

recommended for infants this season and 

young children at increased risk

 For infants born October 2023 through March 2024, 

immunize within 1 week of birth

– Immunize infants with prolonged birth hospitalizations 

shortly before or promptly after discharge

 For all other infants younger than 8 months this season, 

administer as soon as nirsevimab is available assuming 

sufficient availability

 For children 8–19 months and at increased risk for severe 

disease, administer as soon as nirsevimab is available 

assuming sufficient availability

Jones JM, Fleming-Dutra KE, Prill MM et al: https://www.cdc.gov/mmwr/volumes/72/wr/mm7234a4.htm
Nirsevimab (Sanofi and AstraZeneca) is efficacious

against severe RSV among infants entering their first 

RSV season

Two placebo-controlled, randomized trials including pre-term and term infants

Vaccine efficacy estimates (through 150 days after injection):

Medically attended RSVassociated lower respiratory tract 

infections (LTRI):

79.0% (95% CI = 68.5%–86.1%)

Hospitalization for RSVassociated LRTI:

80.6% (95% CI = 62.3%–90.1%)

Griffin MP, Yuan Y, Takas T, et al. https://doi.org/10.1056/NEJMoa1913556 

Muller WJ, Madhi SA, Seoane Nuñez B, et al. https://doi.org/10.1056/NEJMc2214773 

Jones JM, Fleming-Dutra KE, Prill MM, et al. https://www.cdc.gov/mmwr/volumes/72/wr/mm7234a4.htm
Benefits of nirsevimab administration outweigh 

potential risks

 Most common side effects: injection site reactions, rash

What did clinical trial data show about 

safety of nirsevimab?

• The incidence of serious adverse events 

was not increased in those who received 

nirsevimab compared with those who 

received placebo How do we interpret this?

• We anticipate side effects to be mild or 

moderate and like those experienced 

after routine vaccinations

Jones JM, Fleming-Dutra KE, Prill MM et al: https://www.cdc.gov/mmwr/volumes/72/wr/mm7234a4.htm
Limited supply of nirsevimab is a challenge this season

https://emergency.cdc.gov/han/2023/han00499.asp
Other barriers may exist this season

 Your clinic or hospital may or may not have these products available.

 Your local pharmacy may or may not have these products available.

 Pharmacies may require a prescription. 

 Insurers have a year to cover newly approved products.

 Out-of-pocket costs are expensive to individuals (e.g., $295 for Abrysvo; 

$495 for nirsevimab).

 Lack of documentation of maternal vaccination might be a barrier to 

informed decision making for young infants. 
Summary: Two ways to protect infants from severe 

RSV disease

Abrysvo

(Pfizer) is the 

only RSV 

vaccine for use 

during 

pregnancy

Nirsevimab, 

an RSV 

antibody, is 

only given 

to infants
Counseling pregnant patients this season
Healthcare providers are trusted source
Consider raising these key points during shared 

decision-making conversations with pregnant patients 

 Risk of severe RSV for young infants

 Known benefits of the approved products to help prevent severe RSV

 Relative advantages and disadvantages of each product

 Patient preferences

 Local availability of nirsevimab
Sample script to counsel patients

At this point in your pregnancy, you are eligible to get the 

RSV vaccine to protect your baby from a severe respiratory 

illness called RSV. RSV is a common seasonal viral infection 

that can cause babies to get very sick. It can make it hard for 

babies to breathe. We have two options for preventing 

severe RSV illness in babies.

One option is a new vaccine that we give you during 

pregnancy. The vaccine causes you to make antibodies that 

you pass to your baby through the placenta. These 

antibodies help protect your baby early in their life.
Sample script to counsel patient continued

The other option called nirsevimab can be given to your 

baby after birth and works similarly to protect your baby 

from RSV illness after delivery. 

One or the other is recommended, but both are not 

needed for most babies. Keep in mind though that there 

may be limited availability of nirsevimab this season once 

your baby is born.
Advantages and disadvantages of Abrysvo

(Pfizer) during pregnancy

 Advantages

– Immediate protection after birth

– Might be more resistant to potential changes in the virus, 

or variants

 Disadvantages

– Potentially reduced protection in some situations (e.g., if 

birth of baby happens within 14 days of vaccination)

– Potential risk for preterm birth and hypertensive disorders 

of pregnancy
Advantages and disadvantages 

of nirsevimab for young infants

 Advantages

– Protection might last longer than protection 

from maternal RSV vaccine

– Assures direct receipt of antibodies

– No potential risk for adverse pregnancy 

outcomes

 Disadvantages

– Potentially limited availability during 2023-24 

RSV season

– Requires infant injection
Common questions

Which product is better – nirsevimab or maternal RSV 

vaccine? Does one work better than the other? Is one 

safer than the other?

• No studies have directly compared the two products. 

• However, both products have been shown to provide 

significant protection against severe RSV in young babies. 

• Let’s talk about which option might be best for you and 

your family.
Common questions: What is it?

What is the maternal RSV vaccine made of and 

how does it work?

• Abrysvo is a recombinant protein vaccine. It targets 

two F-proteins of the virus (RSVpreF A and RSVpreF B). 

• If you get vaccinated during pregnancy, your body will 

build antibodies against these two RSV proteins. 

• These antibodies will transfer across your placenta to 

your baby while you are pregnant. 

• After birth, if your baby is exposed to RSV early in life, 

your baby will use the antibodies it got from you to 

recognize RSV and fight against it. 
Common questions: Coadministration

Can the RSV vaccine be given at the same time 

as other maternal vaccines?

• Yes, you can receive RSV vaccine at the same 

time as other routine vaccinations, like Tdap, 

COVID-19, and flu. 
Common questions: Receiving both products

Can a baby receive nirsevimab if their mother 

received the RSV vaccine?

• Both products protect babies from severe RSV by 

providing antibodies, either from the mother to 

the baby or directly to the baby. 

• Most babies will likely only need protection from 

either the maternal RSV vaccine or nirsevimab 

(not both). 

• However, there may be some situations in which 

nirsevimab would be recommended for a baby 

after the mother received an RSV vaccine.
Common questions: Prior infection

Should I get the RSV vaccine if I’ve already had 

RSV before?

 Even if you had RSV infection in the past, RSV 

vaccination can help protect infants from severe RSV. 

 There is no specific length of time that you need to 

wait after having RSV infection before you can 

receive an RSV vaccine. 

– Generally, if you have a moderate or severe illness, 

you should wait until you recover before receiving an 

RSV vaccine. 

– If you have a minor illness, such as a cold, you can get 

an RSV vaccine.
Common questions: Insurance coverage

Are these both covered by insurance 

and/or Medicaid?

• Maternal RSV vaccine is covered 

• By Medicaid without cost-sharing for nearly all fullbenefit adult beneficiaries with traditional Medicaid

• By the Vaccines For Children (VFC) program for people 

younger than 19 years

• By most private insurance plans, but companies have 

one year to comply with new recommendations

• Nirsevimab is covered

• By the VFC program

• By most private insurance plans, but companies have 

one year to comply with new recommendations
As a provider, you can facilitate implementation

 Document receipt of maternal RSV vaccination (e.g., via immunization 

information system, electronic health records, written documentation)

 Routinely provide prescriptions for RSV vaccine for pregnant individuals 

who are 32-36 weeks gestation. Clearly indicate pregnancy on the 

prescription to ensure receipt of correct vaccine – Abrysvo (Pfizer).

 Get familiar with your local access

– Call local pharmacies to assess availability of RSV-prevention products

– Ask local hospital about prioritization and availability of nirsevimab

– If your practice does not carry these products or has insufficient 

supply, refer patients to local resources
For more information, contact CDC

1-800-CDC-INFO (232-4636)

TTY: 1-888-232-6348 www.cdc.gov

The findings and conclusions in this report are those of the authors and do not necessarily represent the 

official position of the Centers for Disease Control and Prevention.

Thank you