New vaccines to prevent RSV help address the burden of RSV in older adults and help prevent infection in infants through the vaccination of pregnant individuals.

RSV can affect the lower respiratory tract. While RSV usually causes mild, cold-like symptoms, it can be serious or even fatal in infants, older adults, and people with compromised immune systems.

Estimates suggest that in the United States, RSV infections cause more than 60,000 to 160,000 hospitalizations and 6,000 to 10,000 deaths in older adults each year.

The virus is highly transmissible, and a person can contract it via droplets released into the air when someone who has the virus coughs or sneezes. People can also acquire RSV by touching a contaminated surface or through direct contact with someone who has the virus, such as kissing.

Several vaccines have Food and Drug Administration (FDA) approval to help prevent RSV in adults in the United States. This article explains what an RSV vaccine is, how it works, and who should get it.

At the time of publication, the FDA had approved three vaccines to help prevent RSV in adults in the United States. While these approvals are more recent, the RSV vaccine has been in development for more than 60 years.

RSV vaccine history

Scientists developed an RSV vaccine for infants in the 1960s. However, they stopped its development due to concerns about a severe lung inflammatory response that occurred in some vaccinated infants and resulted in two deaths.

While it has taken time, new technological advances and a better understanding of RSV have resulted in the approval of several vaccines in recent years.

RSV vaccines

Three vaccines have FDA approval for the prevention of RSV in adults ages 60 and over:

Ongoing clinical trials are studying how other populations, such as healthy adults ages 18 to 49 years and high risk adults ages 18 to 59 years, respond to RSV vaccines. These trials will help shape the public guidance on who in this age group would benefit most from and should get the vaccines.

RSV vaccines work by teaching the body to recognize key proteins that RSV uses to attack human cells.

Once a person receives an injection of a vaccine containing these proteins or instructions to make them, the body’s immune system produces antibodies to fight them.

The immune system remembers how to protect the body against this antigen in the future. If the body encounters RSV later, the immune system will be able to quickly recognize the virus and disable it to help prevent infection.

RSV vaccines are based on a stabilized version of RSV’s prefusion F (preF) protein, meaning they contain the mRNA coding for the preF protein. After a person receives the vaccine injection, their body produces this protein.

RSV causes mild, cold-like symptoms in most adults, so vaccines would not be necessary for everyone.

The CDC recommends the RSV vaccine for:

  • everyone who is 75 years or older
  • people ages 60 to 74 years who are at an increased risk for severe RSV
  • pregnant individuals at 32 to 36 weeks gestation

Adults at an increased risk for severe RSV include people who:

  • have certain underlying conditions, such as heart or lung diseases
  • have a weakened immune system
  • live in nursing homes or other long-term care facilities

People ages 60 years or older and pregnant individuals can ask a doctor about getting an RSV vaccine.

The RSV vaccine is currently not an annual vaccine, so a person may not receive a dose every RSV season. Ongoing trials are studying whether adults will require additional RSV vaccines in the future. At the time of publication, only one dose is needed to help protect adults for at least two RSV seasons.

The FDA has approved several vaccines for the prevention of RSV in older adults and infants through the vaccination of pregnant individuals.

Currently, no vaccines are available for all age groups, but clinical trials studying RSV vaccines in healthy individuals and other high risk populations are ongoing.

Until then, it is important to take extra care to help prevent transmission of the virus by:

  • washing hands often
  • avoiding close contact with people who are sick
  • disinfecting frequently touched surfaces
  • staying home while sick