Respiratory syncytial virus (RSV) is a common virus that affects the lungs and airways. For most children, RSV causes mild, cold-like symptoms. However, in some, particularly infants, RSV can lead to serious illnesses, such as bronchiolitis (inflammation of the small airways), pneumonia (lung infection) or breathing problems that may require oxygen or intensive care.
RSV season occurs every year in the U.S., beginning in fall and peaking in winter, but the timing and intensity of each season can vary.
Why does my child need protection against RSV?
RSV is the leading cause of infant hospitalization in the U.S. Almost all children will be infected with RSV by age two. Infants often catch RSV from siblings or family members who seem only mildly sick. RSV can become serious very quickly in infants, especially in the first few months of life.
Each year, 50,000–80,000 children younger than 5 are hospitalized due to RSV. About 2 to 3 out of every 100 children with RSV need to be hospitalized because they have trouble breathing or feeding. Supportive care in the hospital is the only available treatment for RSV lower respiratory tract illness. That’s why prevention is so important.
Which immunizations protect against RSV?
There are two safe and effective ways to help prevent severe RSV illness.
Pregnant individuals can receive the RSV vaccine between 32 and 36 weeks of pregnancy, helping protect their baby through maternal antibodies. The vaccine is given to pregnant individuals from September through January to best protect infants born during the RSV season.
If an infant’s mother did not get the RSV vaccine during pregnancy, infants should receive an RSV antibody. A dose is recommended for all infants under 8 months entering their first RSV season. One dose protects infants for about 5 months, the length of RSV season.
Are they safe?
Yes. Very few side effects have been reported among infants receiving the RSV antibody. Side effects in infants are mild and uncommon but may include rash and injection site tenderness. In pregnant individuals who received the RSV vaccine, side effects included pain at the injection site, headache, muscle pain or nausea. The vaccine is given close to the end of pregnancy which helps reduce any possible risk of very early preterm birth.
Are they effective?
RSV immunization is very effective – the RSV antibody is about 80% effective at preventing hospitalizations due to RSV in infants. Vaccination with the RSV vaccine during pregnancy is 70-80% effective in preventing hospitalization of newborns due to RSV infection.