COVID-19 Vaccine & Booster Information For People With Cancer & Others with Weakened Immune Systems

Patient receives a COVID-19 vaccine

People with cancer should get more COVID-19 vaccine doses than the general public.

Memorial Sloan Kettering Cancer Center (MSK) and the Centers for Disease Control and Prevention (CDC) recommend people with cancer stay up to date on their COVID-19 vaccinations. They should get at least 1 updated (bivalent) shot that protects against the most recent strains of the virus. Cancer and its treatment can severely weaken the immune system, and people with cancer are particularly susceptible to severe COVID-19.

Mini Kamboj, MSK’s Chief Medical Epidemiologist, explains what you need to know about COVID-19 vaccines if you’ve had cancer.

This information is for people with weakened immune systems (called immunocompromised).

If you are not immunocompromised, please visit the CDC’s website for information about how many vaccine doses you should receive and when:

Stay Up to Date with Your COVID-19 Vaccines »

What to Know about the Updated (Bivalent) Vaccine

You may have read about the updated COVID-19 bivalent vaccine that provides protection against Omicron subvariants BA.4/5. We recommend our patients strongly consider getting at least 1 dose of the bivalent vaccine to have the best possible protection from COVID-19. Patients undergoing cancer treatment have the option of getting a 2nd bivalent dose if at least 2 months have passed since their last COVID-19 shot.

Read more about updated (bivalent) shots »

Who Is At Risk for Severe COVID-19

The CDC says that people who are “moderately to severely immunocompromised” are at increased risk of severe COVID-19 illness.

For people with cancer, this includes:

  • People with blood cancer.
  • People who are actively being treated for solid tumors with chemotherapy — and some people being treated with immunotherapy.
  • People without a functioning spleen (called asplenia).
  • People who have undergone a stem cell transplant or received CAR T therapy within the past two years.
  • People who are actively being treated for graft-versus-host-disease (GVHD) with immunosuppressive drugs (for example, sirolimus or Rapamune®).
  • People with primary immunodeficiency disorders (for example, DiGeorge syndrome, Wiskott-Aldrich syndrome).
  • People with active or untreated HIV infection.
  • People actively using high-dose steroids (for example, 20mg of prednisone or more per day for at least 2 weeks).
  • People actively being treated for an immune-related disease (for example, rheumatoid arthritis, Crohn’s disease, or psoriasis) with a tumor necrosis factor (TNF) inhibitor (for example, adalimumab or Humira®).

These eligibility criteria cover the most common situations. If you are receiving another treatment that has weakened your immune system, your doctor will be able to advise you about the timing and total number of doses you need.

Timing: When You Should Get Your Vaccine Doses if You Are Immunocompromised

The schedule of when to get your vaccine doses varies based on what brand of vaccine you get. Information on the CDC’s website can help guide you:

COVID-19 Vaccines for People who are Moderately or Severely Immunocompromised »

Vaccine Side Effects

You could experience soreness at the injection site, fatigue, headache, body aches, and fever. These symptoms don’t last long — about 1 to 3 days.

A serious but very rare side effect is heart inflammation. The group that is most likely to develop this condition after getting the COVID-19 vaccine is young men aged 12 to 39. Because of this, this group can wait longer between their first and second dose (of their primary vaccine series) to reduce their risk of myocarditis or pericarditis. They should wait 8 weeks between shots.

Read more about heart inflammation, a rare vaccine side effect »

Revaccination After Certain Treatments

Certain cancer treatments can completely or partially wipe out a patient’s immune system. Because of this, anything that your immune system learned before cancer treatment now may be completely gone. Your immune system needs to relearn how to fight COVID-19.

If you received any COVID-19 vaccine shots before, during, or shortly after cancer treatment, you may need to be revaccinated if your doctor thinks your immune system has recovered enough to respond to the vaccines. Everyone who is currently eligible to be vaccinated is also eligible to be revaccinated if they meet the below criteria.

You may need to be revaccinated if you received any of these treatments:

  • Hematopoietic cell transplantation (also called a bone marrow transplantation or stem cell transplantation)
  • CAR T therapy
  • Treatment with B cell depleting drugs such as rituximab or Rituxan®

Your healthcare team will determine whether you should be revaccinated and the best time to get the shots. Only healthcare providers can order revaccination for their patients after careful evaluation of eligibility. If you think you meet any of the criteria for revaccination, you should talk to your healthcare team.

How Else to Protect Yourself

Even when you are completely up to date on your COVID-19 shots, you must still take certain precautions to protect yourself from COVID-19. You should:

  • Wear a mask indoors and outdoors when you are around anyone you don’t live with. Read more about masking »
  • Wash your hands frequently for at least 20 seconds.
  • Stay 6 feet apart from others you don’t live with.
  • Avoid crowds and poorly ventilated indoor spaces.
  • Encourage your close friends, family members, neighbors, and co-workers to be vaccinated.

If you develop symptoms of COVID-19, contact your care team and get tested. Learn more about testing »

Getting Vaccinated at MSK

Adults can schedule their vaccinations at MSK by using this link.

A parent or guardian of a pediatric patient must call their child’s primary doctor at MSK to schedule a vaccination appointment.

If you have questions about getting vaccinated, please call your MSK doctor’s office.

Please bring your CDC-issued COVID-19 vaccine card to all vaccination appointments. This is important for us to confirm the date and brand of your doses.

MSK is offering vaccinations at the following locations:

However, our patients don’t need to wait to get vaccinated at MSK. We encourage them to look for a vaccination location with availability near you, using the following links:


May 5, 2023


Additional Resources