RSV (Respiratory Syncytial Virus)

What is it and how is it spread? 

RSV, or respiratory syncytial (sin-SISH-uhl) virus, is a common virus that infects the lungs and airways. Most cases are mild and result in flu-like symptoms that last from 3-8 days, but severe cases can lead to pneumonia or bronchiolitis that can require hospitalization.

RSV is spread via droplets, and the virus is hardy enough to survive on hard surfaces for hours at a time.

RSV circulates seasonally like the flu—most often, infections pick up in the fall and peak in the winter, but the timing and seriousness can vary from year to year.

Who's at Risk? 

Complications from RSV can happen to people in any age group, but those the most at risk are young infants, immunocompromised individuals, individuals with lung or heart disease, and adults over the age of 65.

Most kids will get RSV at least once before their 2nd birthday, but unfortunately, we do not develop long-lasting immunity.

RSV is the leading cause of hospitalization in infants in the USA. Among adults and children, RSV causes an estimated 58,000 hospitalizations each year, with 100-500 deaths among children younger than 5 years old and 177,000 hospitalizations with 14,000 deaths among adults 65 or older. 

RSV Vaccine

For Adults Age 60+: There are two RSV vaccines approved for adults ages 60 years and older, including (Pfizer's Abyrsvo and GlaxoSmithKline (GSK)'s Arexvy. Adults should consult their healthcare provider to see if vaccination against RSV is right for them. 

For Pregnant Persons: On September 22, 2023, the CDC recommended the first RSV vaccine (Pfizer for pregnant people to protect their newborn from severe RSV illness. This new vaccine, Pfizer’s Abrysvo, has been shown to reduce the risk of RSV hospitalization for babies by 57 percent in the first six months after birth. The one-dose vaccine is given seasonally to pregnant people during weeks 32 through 36 of pregnancy.

The vaccine is one of two new tools we have this season to protect babies from severe RSV illness. 

RSV Antibody Medication

Nirsevimab (trade name Beyfortus) is a new monoclonal antibody medication that can be given to infants and some young children. Nirsevimab is considered an immunization but it is not technically a vaccine because it does not cause the immune system to create its own antibodies. Instead, it provides passive immunity through a single injection of ready-made antibodies that bind to an infection and block it from entering healthy cells.

Eligibility & Dosage Recommendations:

  • 1 dose of nirsevimab for all infants younger than 8 months born during or entering their first RSV season.
  • 1 dose of nirsevimab for infants and children 8–19 months old who are at increased risk for severe RSV disease and entering their second RSV season.

For more information about RSV vaccines and nirsevimab, click here.

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