You can get RSV more than once in your lifetime. In fact, you’re likely to get it multiple times throughout your life. You can even get RSV twice in the same in season. But later infections tend to be less serious.

In the late months of 2022, cases of respiratory syncytial virus (RSV) spiked in the United States.

Cases typically start in the fall, peak during the winter, and carry on through early spring. But precautions related to the COVID-19 pandemic in the preceding years meant that RSV cases weren’t as prevalent. Once the precautions relaxed, RSV began to spread.

RSV is the leading cause of hospitalization among children younger than age 1. It usually causes upper respiratory tract infections in children and adults. But it can also lead to lower respiratory tract infections, like bronchiolitis or pneumonia, especially in young children.

With the noticeable increase in cases, you may be wondering if, like the flu or COVID-19, you can get RSV more than once. And if so, can you get it twice in the same season, or even the same month? Keep reading to learn more.

Your body does not produce long-term immunity against RSV. That’s one of the reasons the virus is so common and why you can get it more than once.

Some viruses, like influenza, have many different genetic strains that change from year to year, which makes reinfection more common. But this is not true of RSV. Although there are different strains, it’s largely genetically stable.

Experts aren’t entirely sure why immunity from RSV doesn’t last very long. But they think the virus itself may interfere with your immune response. This process is called immunomodulation.

About 90% of people get RSV before age 2. This first infection usually provides some degree of immunity. But this immunity is short-lived and only partial. You’re still able to contract the virus later in life, though it may not affect you to the same degree.

Most people will experience a second RSV infection in their lifetime. According to a 2016 study, about 35% of children have already had a second infection before their third birthday.

While it’s possible to get RSV twice in the same season, it’s not very common. According to a 2021 review of studies, your risk of getting RSV again after an initial infection is about 70% lower within the first 6 months.

Research suggests that your body starts to have an immune response to RSV within 5 to 10 days. That protection lasts anywhere from 3 to 12 months before it starts to decline.

According to 2019 research, up to 36% of people may experience reinfection at least once each season.

You usually develop partial immunity after an RSV infection. That means a second infection likely won’t affect you as much.

For example, RSV is more likely to cause a lower respiratory tract infection the first time around. Your lower respiratory tract includes your windpipe (trachea), the airways in your lungs (bronchi and bronchioles), and the air sacs in your lungs (alveoli).

About 40% of people with a first RSV infection develop bronchiolitis, inflammation of the bronchioles. In rare cases, you may also develop pneumonia, an infection of the alveoli. But your risk of a lower respiratory tract infection decreases each time you get RSV.

You’re still likely to experience upper respiratory tract infections when you get RSV later in life. They affect your nose, mouth, throat, sinuses, and voice box.

RSV symptoms

Common symptoms of RSV include:

According to the Centers for Disease Control and Prevention (CDC), RSV symptoms usually appear within 4 to 6 days of infection and should go away with 1 to 2 weeks.

A clinician will usually diagnose RSV based on your medical history and symptoms. But they may want to confirm a diagnosis, especially if reinfection occurs in the same season. They can do this with any of the following tests:

  • real-time reverse transcriptase-polymerase chain reaction (rRT-PCR), which involves a mouth swab
  • antigen test, which works best for children
  • viral culture
  • blood test

Anyone can get RSV a second time. But some people may be more likely to experience one or more reinfections. They include:

  • infants
  • children
  • pregnant people
  • older adults
  • people with a weakened immune system

You can help prevent any infection (first or otherwise) of RSV and other respiratory viruses by doing the following:

  • Wash your hands regularly with soap and water for at least 20 seconds.
  • Cover your coughs and sneezes. Use a tissue or shirt sleeve rather than your hand.
  • Clean frequently used surfaces and objects, like countertops, doorknobs, and cell phones.
  • Avoid touching your face or eyes.
  • Avoid close contact and sharing objects with people who have RSV.

After you get RSV, your body has an immune response. But that response isn’t complete. It starts to fade over time — sometimes within a few months.

For this reason, most people get an RSV infection again later in life. More than one-third of people get a second infection by the time they turn 3 years old.

But that partial immunity still helps. Reinfections are typically much less serious. Complications like bronchiolitis or pneumonia are more likely with a primary infection. If you get RSV a second (or third or fourth) time, you’re more likely to have cold-like symptoms.