RSV Immunization for Children 19 months and Younger
Nirsevimab (Beyfortus) is an immunization recommended for all infants younger than 8 months of age who are born during—or who are entering—their first Respiratory Syncytial Virus (RSV) season. Except in rare circumstances, most infants younger than 8 months of age do not need nirsevimab if they were born 14 or more days after their mother got RSV vaccine. Nirsevimab is also recommended for some children age 8 through 19 months who are at increased risk for severe RSV disease and entering their second RSV season.
When is RSV season?
In most regions of the United States, RSV season starts in the fall and peaks in the winter, but the timing and severity of RSV season can vary from place to place and year to year. Talk to your child’s health care provider about when is the right time for your child to get nirsevimab based on the RSV season in your community, so that your child is protected against RSV disease.
How can RSV disease be prevented?
RSV disease can be prevented either by giving antibody products to infants and young children, or by giving their mothers RSV vaccine during pregnancy. For most babies, either the maternal RSV vaccine or the preventive antibody is recommended to prevent RSV disease, but not both.
RSV preventive antibody products
There are two RSV antibody products that can help prevent severe RSV disease in infants and young children: Nirsevimab (Beyfortus), and Palivizumab (Synagis).
Nirsevimab is recommended for:
- All infants younger than 8 months of age born during RSV season or entering their first RSV season. Except in rare circumstances, most infants younger than 8 months of age do not need nirsevimab if they were born 14 or more days after their mother got RSV vaccine.
- Some children aged 8 through 19 months who are at increased risk for severe RSV disease and entering their second RSV season.
Palivizumab (Synagis) use is limited to:
- Some children younger than age 24 months of age with certain conditions that place them at increased risk for severe RSV disease. It must be given once a month during RSV season.
An RSV vaccine (Abrysvo, Pfizer) is recommended during weeks 32 through 36 of pregnancy to prevent severe RSV disease in infants. This vaccine should typically be given September through January.
Who should get nirsevimab?
- Nirsevimab is recommended for infants younger than 8 months of age who were born during or are entering their first RSV season if
- The mother did not receive RSV vaccine during pregnancy.
- The mother’s RSV vaccination status is unknown.
- The infant was born within 14 days of maternal RSV vaccination.
Most infants whose mothers got the RSV vaccine don’t need to get nirsevimab, too.
- Some infants and young children 8 through 19 months of age who are at increased risk for severe RSV disease should receive nirsevimab shortly before the start of their second RSV season:
- Children who were born prematurely and have chronic lung disease
- Children with severe immunocompromise
- Children with cystic fibrosis who have severe disease
- American Indian and Alaska Native children
Children who should get nirsevimab but have not yet done so may get nirsevimab at any time during RSV season.
How is nirsevimab administered?
Nirsevimab is administered as a shot into the thigh muscle. Only a single dose (i.e., one shot) of nirsevimab is recommended during an RSV season.
Who should not get nirsevimab?
Children 8 months old and older who are not at increased risk for severe RSV disease should not receive nirsevimab.
Except in rare circumstances, most infants younger than age 8 months do not need to get nirsevimab if their mothers got the RSV vaccine at least 14 days before delivery.
Infants and children with a history of serious allergic reactions to nirsevimab or any of its components should not get nirsevimab.
Infants and children with bleeding disorders such as hemophilia should get nirsevimab. But, as with all shots given into a muscle, parents should notify their child’s healthcare provider so additional precautions can be taken.
Infants and children who have a moderate or severe acute illness usually should wait until they recover before getting nirsevimab. Your child’s healthcare provider may decide to postpone giving nirsevimab until a future visit when your child feels better. Children with minor illnesses, such as a cold, can receive nirsevimab.
How well does nirsevimab work?
Nirsevimab reduces the risk of severe RSV disease by about 80%. One dose of nirsevimab protects infants for at least 5 months, the length of an average RSV season. Because nirsevimab does not activate the immune system, protection is most effective in the weeks right after nirsevimab is given and lessens over time. Nirsevimab does not provide long-term protection to RSV disease, but it does protect infants when they are most at risk of getting very sick from RSV. As children get older, they are less likely to get very sick from RSV.
How does nirsevimab prevent RSV disease?
Nirsevimab contains monoclonal antibodies, which are man-made proteins that protect against RSV. Though it does not activate the immune system the way an infection or vaccine would, a nirsevimab shot provides protection similar to that of a vaccine.
The protection that nirsevimab provides is called “passive immunity” because it does not come from the person’s own immune system. Instead, the protection comes from antibodies produced outside a person’s body.
On the other hand, the protection that vaccines provide is called “active immunity” because the antibodies are made by a person’s own immune system. “Active immunity” requires a person’s immune system to take action to defend itself.
What are the possible side effects of nirsevimab?
Side effects after Nirsevimab were uncommon in clinical trials. The most common side effects after nirsevimab are pain, redness, or swelling where the injection was given, and a rash. No serious allergic reactions occurred in the clinical trials.
As with any immunization, there is a very remote chance that nirsevimab could cause a severe allergic reaction, other serious injury, or death.
If you have any questions about side effects from nirsevimab, talk with your child’s health care provider.
If your child experienced side effects after receiving nirsevimab it can be reported to the FDA or CDC. Your healthcare provider might file the report, or you can do it yourself by phone or through the MedWatch or VAERS websites.
- Report side effects that happen after getting nirsevimab to the MedWatch website or by calling 1-800-FDA-1088.
- If your child also received any vaccine on the same day as nirsevimab, the side effects also may be reported to VAERS, the Vaccine Adverse Event Reporting System through the VAERS website or by calling 1-800-822-7967.
How Do I Pay for Nirsevimab?
Vaccines for Children (VFC) program
Nirsevimab will be covered by VFC, a federally funded program that provides vaccines at no cost to children who might not otherwise be vaccinated because of inability to pay. Children younger than 19 years of age are eligible for the VFC Program if they belong to one or more of the following groups:
- American Indian or Alaska Native
Private health insurance. Many private health insurance plans cover nirsevimab, but there may be a cost to you depending on your plan. Contact your insurer to find out.