
When it’s functioning well, your immune system easily traps and fends off the respiratory syncytial virus (RSV) in the upper respiratory tract. As your immune system fights the infection, you might feel stuffed up. Your nose might run, and you may experience a dry cough, a low-grade fever, a sore throat, sneezing and headache.
“People with typical immunity may not even know they have RSV. They may assume they have a common cold,” says Abinash Virk, M.D., an infectious disease expert at Mayo Clinic.
However, cancer can weaken your immune system in several ways. Some types of cancer, such as leukemia, change how immune cells work, making them less effective. On top of that, chemotherapy can affect your bone marrow and reduce your white blood cell count — and both are important in fighting off infections.
“Because their immune systems are more compromised, people undergoing treatment for cancer are at a higher risk of having a more severe infection of RSV,” says Dr. Virk.
Instead of remaining in the nose and throat, RSV infection can spread to the bronchi and lungs, leading to pneumonia or bronchiolitis, an inflammation of the small airway passages that lead to the lungs.
“This makes it more difficult to breathe, similar to when infection with a COVID-19 or influenza virus invades the lungs,” says Dr. Virk.
Other lower respiratory symptoms include severe cough, rapid breathing and wheezing, a high-pitched noise usually heard on the exhale. If you experience any of these symptoms, make an appointment with a healthcare professional to get tested for RSV and other dangerous viruses. It is important to get tested, as there are specific treatments for these viral respiratory tract infections.
Below you’ll find answers to questions people with cancer tend to ask about the RSV vaccine.
Should people with cancer get the RSV vaccine?
In 2023, the FDA approved two RSV vaccines, Abrysvo (Pfizer) and Arexvy (GSK), for people 60 and older. Both vaccines use altered RSV protein to stop the virus from attaching to respiratory cells.
“It’s not a live virus, so the vaccine can’t give you RSV,” says Dr. Virk. “We know it’s effective and safe. In clinical trials, the vaccines were 80% to 90% effective at preventing the serious infections that tend to land people in the hospital.”
Cancer treatment may reduce your immune system’s antibody response to the vaccine, but it likely won’t render it completely ineffective.
“We don’t know if the vaccine is as effective in people undergoing active treatment for cancer, but we believe it will be better than nothing,” says Dr. Virk.
When is the best time to get the vaccine?
Talk to a healthcare professional about getting the vaccine in the early fall, before RSV and other viruses tend to circulate.
Know that some cancer treatments and bone marrow transplants may greatly decrease the immune protection from your vaccines. Ideally, get vaccinated before undergoing treatment, says Dr. Virk. However, if you’ve recently had a bone marrow or stem cell transplant, talk with your healthcare team about the best time to get vaccinated, as it can vary based on your treatment.
Is it safe to get the RSV vaccine along with other vaccinations?
You may be able to get the RSV, influenza and COVID-19 vaccines during the same visit, says Dr. Virk. That said, it’s also OK to spread out the shots if you prefer to do so. Talk to your healthcare team to come up with the best vaccination plan for you.
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