Immunizations

Some cancer treatments, like chemotherapy and radiation therapy, can cause a weak (suppressed) immune system. Your immune system defends the body against infection and disease. When your immune system is not working properly it may be called immunosuppression or immunocompromised. A weak immune system puts you at risk of infections. Some of these infections may be prevented through immunization (also called vaccination). Vaccination is treatment with a vaccine to protect against a disease or infection.

Your risk of infection can vary depending on if you’ve had vaccinations before, if you’ve had any infections and how weak your immune system is. Not all cancer treatments have the same risk. For example, someone having chemotherapy for leukemia is likely to be more at risk of an infection than someone having chemotherapy for a solid tumour.

Talk to your doctor or healthcare team if you have questions about immunizations during or after cancer treatment. Avoid vaccinations if you are being treated for cancer. There are different types of vaccines. If your immune system is weak, receiving a live vaccine can be dangerous. Other vaccinations, such as inactivated vaccines, don’t pose a safety risk but likely won’t work as well if your immune system isn’t working properly.

The Canadian Immunization Guide discusses immunization of people with certain medical conditions, such as those with weak immune systems. Find out more about immunization of immunocompromised persons.

There are specific guidelines for people who have received stem cell transplants (also called bone marrow transplants). If you have a transplant, you will get immunizations before the transplant that are tailored to your specific situation. Once the immune system has recovered after the transplant, you will need to receive the vaccines again.

If you are receiving radiation therapy to your arm or upper body, vaccines should be given on the opposite side. If you are taking combination checkpoint inhibitors, you should not receive any vaccinations.

The Canadian Immunization Guide also has immunization information for travellers. You may need to be immunized several months before a trip so that immunizations have time to take effect. The actual immunizations required will vary depending on your age, health and medical conditions as well as where and why you are travelling. Talk to your healthcare team about immunizations needed for travelling.

There are different types of vaccines used in immunizations.

Inactivated vaccines use the killed version of a virus that causes a disease or infection. Inactivated vaccines may also be called killed vaccines or non-live vaccines. In general, you should get an inactivated vaccine at least 2 weeks before receiving chemotherapy or other treatments that weaken the immune system. If inactivated vaccines are used during chemotherapy, they may only give minimal protection and should be given again when the immune system has recovered, generally at least 3 weeks after treatment is finished.

Live vaccines use a weakened form of a virus that causes a disease or infection. People with weak immune systems should not get live vaccines. Live vaccines should be given at least 4 weeks before chemotherapy or other treatments that weaken the immune system or at least 3 to 6 months after treatments are finished.

If your immune system is weak, your healthcare team may suggest that people close to you receive all currently recommended vaccinations such as varicella (chicken pox) and influenza (flu). This may include your spouse or partner, children, parents and siblings or people who live with you. This will help reduce your chance of getting these diseases.

If you had a stem cell transplant, you may have to avoid children or people recently immunized with a live vaccine such as the nasal spray used for influenza.

People with cancer are at higher risk of having the flu so getting the flu shot (influenza vaccine) is important. The flu shot is usually available in the fall each year. There are different types of flu vaccine. Inactivated flu vaccine is given as a shot or injection. Live flu vaccine is given as a nasal spray. People with cancer should avoid the live flu vaccine.

Talk to your doctor or healthcare team before getting the flu vaccine. There are general guidelines for people with cancer or people undergoing treatment for cancer.

• It is usually safe for people with cancer to get the inactivated vaccine.
• People with cancer should not get the live vaccine during treatment and for up to 6 months after treatment.
• People receiving chemotherapy should have the flu shot either 2 weeks before chemotherapy starts or in between chemotherapy cycles.
• People having targeted therapy or radiation therapy can have the flu shot.
• People having immunotherapy such as checkpoint inhibitors should discuss with their doctor if and when to have the flu vaccine.
• Families, caregivers and household members should receive the flu shot.

People with cancer, especially blood cancer and lymphoma, have a higher risk of developing shingles (also called herpes zoster). Shingles is a re-activation of the varicella zoster virus that causes chicken pox early in life. People who were vaccinated for chicken pox as a child are not at risk of shingles. Almost everyone who was not vaccinated had chicken pox even if they were not aware of it. Therefore, they are at risk of developing shingles. There are different types of shingles vaccines. Shingrix is an inactivated vaccine that is safe for people with cancer. Shingles can be almost completely prevented with the use of Shingrix.

Talk to your doctor or healthcare team before getting the shingles vaccine. If possible, it is better not to get vaccinated during chemotherapy or for 6 months afterward because this may interfere with its effectiveness. Shingrix requires 2 injections spaced 2 to 6 months apart.

The pneumonia vaccine (pneumococcal vaccine) lasts 10 to 15 years. Your doctor may recommend getting this vaccine if you have multiple myeloma, lung cancer, chronic lymphocytic leukemia or lymphoma because you are at higher risk of pneumonia. If possible, the vaccine should be given before treatment starts.

Other vaccines that your doctor may discuss with you include:

• tetanus, diphtheria and pertussis vaccine
• hepatitis B vaccine
• meningococcal vaccine
• HPV vaccine
• hepatitis A vaccine