On September 22, 2023, the CDC recommended a new maternal RSV (respiratory syncytial virus) vaccine for individuals who are pregnant. This is a big step in providing options to expectant parents to help prevent severe RSV illness in infants born during RSV season. RSV is the leading cause of hospitalization in babies, with more than 500,000 infants admitted to the emergency department and 58,000-80,000 children younger than five hospitalized every year.
“The new preventive measures against RSV are game changers. Having to watch my one-year-old twin grandsons spend two nights in a pediatric intensive care unit was emotionally draining. I, personally, and as the Chief Medical Officer of the American Lung Association, am grateful for these advances,” says Dr. Albert Rizzo.
Pfizer’s RSV vaccine, named Abrysvo, was approved by the FDA in August but needed CDC recommendation before becoming available. This RSV vaccine is recommended for individuals who are pregnant and between 32 and 36 weeks, and for those who are expecting to give birth during RSV season, which is September through January for most of the United States.
This single immunization works by protecting infants in utero by passing antibodies from the parent through the placenta. Passive immunity has worked for other immunizations, such as whooping cough, as protection lasts for the first few months of infancy. The maternal RSV vaccination provides protection against severe illness in the baby for up to six months after birth and protection declines over time.
Another Option in RSV Infant Protection
In August 2023, the CDC approved an RSV preventative antibody that has been proven to reduce the risk of RSV related hospitalizations by 80%. This one dose monoclonal antibody, called nirsevimab (Beyfortus), is recommended by the CDC for all infants younger than 8 months born during or entering their first RSV season. It is also recommended for infants and children 8–19 months old who are at increased risk for severe RSV disease and entering their second RSV season.
The preventative antibody offers protection through passive immunity where external antibodies are delivered directly to the infant. “These antibodies are proteins that the body’s immune system uses to fight off harmful germs. Preventive antibodies are immunizations that provide protection against a virus, in this case, RSV,” explains Dr. Rizzo.
“While both are immunizations, the way they provide protection is different. Nirsevimab is an immunization that provides antibodies directly to the recipient. Traditional vaccines are immunizations that stimulate the recipient’s immune system to produce antibodies,” Dr. Rizzo concludes.
A single dose of the vaccine is proven to protect an infant for at least five months, or the average length of the RSV season. The most common side effects are pain, redness or swelling at the injection site.
Though you should consult your healthcare provider, most infants will only need protection from either the maternal RSV vaccine or the preventative antibody, not both. An exception may occur if a baby is born less than two weeks after maternal immunization.
Other Vaccines Recommended This Season
The 2023 virus season is the first time vaccines are available for all the three major respiratory illnesses: flu, COVID-19 and RSV. It is recommended that everyone 6 months and older receive an annual flu vaccine. It is also recommended that everyone 6 months and older stay up to date with their updated COVID-19 vaccine.
For more information about RSV visit Lung.org/RSV.
Blog last updated: October 2, 2023