Vaccinations and Flu Shots for People with Cancer

Vaccines, also called immunizations or vaccinations, are used to help a person’s immune system recognize and fight off harmful germs, such as bacteria or viruses. Vaccines are often made up of part of the germ, a weakened or killed (inactivated) version of it, or a very similar substance. When the vaccine enters the body, it helps the immune system learn how to fight off the germ, without actually causing the disease. This can help lower the risk that a person will get sick if they’re exposed to the germ in the future.

Should people with cancer get any vaccines?

People with cancer might be able to get some vaccines (and some might even be recommended). This depends on factors such as:

• The type of cancer a person has
• If the person is getting cancer treatment (and if so, which type of treatment)
• The type of vaccine the person would be getting
• The state of the person’s immune system, as well as their overall health

The concern about whether a person with cancer should get a vaccine is based mainly on whether they have a weakened immune system. People with cancer might have a weak immune system for different reasons. For example: 

• The cancer itself might weaken the immune system. (This is especially true for some blood cancers such as leukemias and lymphomas.)
• Some types of cancer treatment, such as chemotherapy, immunotherapy, radiation therapy, or a stem cell transplant, can weaken the immune system.
• Other health issues might also lead to a person having a weakened immune system.

In some situations, it’s important that people with weakened immune systems get certain vaccines (such as the flu and COVID vaccines), because these people are often more likely to get seriously ill if they do get an infection.

At the same time, there are reasons why vaccines might not be recommended for people with weakened immune systems.

First, vaccines might not always be helpful for these people. Even if someone gets a vaccine, their immune system might be too weak to learn how to fend off the germ. Because of this, doctors will often advise waiting until the immune system is stronger before giving the vaccine. In some situations, such as when there’s a high risk of infection, doctors might still advise getting the vaccine, as it might still offer some protection.

A second concern is that some vaccines could be harmful in people with weak immune systems. This is especially true of vaccines made from live, weakened viruses (see below). These types of vaccines don’t usually cause problems in people with healthy immune systems. But they might make people with weak immune systems very sick, so they’re generally not given to them.

It’s important to know which vaccines are safe for people with weak immune systems. Before you get any vaccine, talk to your doctor about your cancer, cancer treatment, risk factors for the vaccine-preventable disease, whether you need the vaccine, and the best time for you to get it.

Live versus inactivated vaccines

Some vaccines are made up of killed (inactivated) viruses, while others contain live (but weakened) viruses.

For people with cancer: In general, anyone with a weak immune system should not get any vaccines that contain live viruses. These vaccines can sometimes cause serious infections in people with weak immune systems.

Your doctor can help guide you about which vaccines are safe while your immune system is weak. Be sure to also talk to your doctor before anyone you spend a lot of time with (such as your children or other household members) gets any vaccines.

For family members and caregivers of people who have cancer: If you live with or spend a lot of time with a person who has cancer and might have a weakened immune system, it's important to talk to the doctor if you or anyone close to you is due for a vaccination of any kind. Usually, most age-appropriate vaccines can be given, but there are some exceptions.

Flu vaccines

The Centers for Disease Control and Prevention (CDC) recommends everyone 6 months and older get a flu vaccine each year, although there are some rare exceptions. 

The flu shot is a vaccine that is given to reduce your risk of getting influenza (a viral infection often called "the flu"). In people with cancer and weakened immune systems, it's important to prevent the flu because it can be serious and sometimes life-threatening. It is recommended that people with cancer get the flu shot that has an inactive (dead) flu virus every year. There is usually a different kind of flu virus expected each year, so the flu vaccines are a little different each year to help them be as effective as possible. Your cancer care team will tell you when the best time to receive the flu vaccine is depending on your cancer type and treatment.

The nasal mist version of the flu vaccine contains a weakened version of the live virus. People with cancer should not get the nasal mist flu vaccine.

For family members and caregivers of people with weakened immunity: It is recommended that people who live with or care for a person at high risk for flu-related problems get the flu vaccine, too. This means that if you’re being treated for cancer, your family members, caregivers, and children aged 6 months and older living at home should get the flu shot.

Family members and caregivers of a person with cancer can usually get the nasal spray (at least in some flu seasons) unless the person has a severely weakened immune system and/or is being cared for in a germ-protected area. For example, household members should not get the nasal mist vaccine if a family member has recently had a stem cell or bone marrow transplant.

Talk to your doctor for more information or if you have questions about your specific situation.

COVID-19 vaccines

Vaccines that can help protect against COVID-19 are now available. In people with weakened immune systems, it's important to protect against COVID-19 because infections can be serious and sometimes life-threatening.

COVID-19 vaccines are made of either messenger RNA (mRNA, a type of genetic material) or a protein from the virus that causes the disease. These vaccines do not contain live viruses, so they are safe for people with weakened immune systems.

As with the flu, the virus that causes COVID-19 can change (mutate) over time, which can make previous vaccines (and previous COVID infections) less likely to be protective if a person is exposed to a newer version of the virus. 

The CDC recommends everyone 6 months and older get the most updated version of the COVID vaccine. However, there are some situations in which a person might be advised to wait to get the vaccine, such as if they have a severely weakened immune system.

For family members and caregivers of people with weakened immunity: It’s also recommended that people who live with or care for a person at high risk for COVID-related problems get the vaccine. This means that if you have a weakened immune system, your family members, caregivers, and children aged 6 months and older living at home should get the COVID vaccine.

Talk to your doctor for more information or if you have questions about your specific situation.

To learn more about these vaccines, see COVID-19 Vaccines in People with Cancer.

Respiratory syncytial virus (RSV) vaccines

In healthy older children and adults, RSV infection can cause symptoms like those from a common cold. But in very young children, older adults, and people with weakened immune systems, symptoms from an RSV infection can be more severe.

RSV vaccines are available for adults aged 60 and over. These vaccines are made of RSV proteins, not live viruses, so they are safe to give to people with weakened immune systems.

The CDC recommends that people 60 and older discuss whether to get the RSV vaccine with their doctors.

MMR (measles-mumps-rubella) vaccine

This vaccine is used to protect people from 3 viral diseases: measles, mumps, and rubella.

People who have weak immune systems should not get the MMR vaccine because it contains live viruses. But it’s usually safe for other household members to get it. If needed, your doctor may consider giving you the vaccine before cancer treatment starts.

Talk to your doctor for more information or if you have questions about your situation.

After exposure to measles: If you have a weakened immune system and are exposed to someone with measles, let your doctor know right away. Sometimes, medicines can be given to help fight the measles infection before it starts.

Pneumococcus (pneumococcal pneumonia) vaccine

This vaccine can help people with weak immune systems fight off certain lung, blood, or brain infections caused by certain bacteria. Your doctor may recommend one or more doses of the pneumococcal vaccine, depending on your age and health. In cases where people are having their spleen removed, this vaccine may be given before surgery or sometimes after surgery.

Ask your doctor if you need to get the pneumococcal vaccine and when you need to get it.

Meningococcal vaccines

This vaccine helps prevent meningococcal disease, which can cause meningitis or other infections. This vaccine is typically not given during cancer treatment. It may be offered before treatment, or after a person’s immune system has recovered. In cases where a person is having their spleen removed, this vaccine may be given before surgery.

Talk to your doctor to see if and when you may need to get the meningococcal vaccine.

Polio vaccine

This vaccine is used to prevent polio, a viral infection linked to severe illness and physical disability. Since the vaccine came out in 1955, polio has become rare in the US.

Children who have weak immune systems, as well as their siblings and others who live with them, only should get inactivated polio virus vaccines. Most doctors in the United States use only the inactivated polio vaccine, but you should ask to be sure. The older oral polio virus vaccine (which is taken by mouth) contains a live virus. People who get the live virus vaccine can pass the virus on to people with weak immune systems.

Varicella (chickenpox) vaccine

This vaccine is intended to prevent chickenpox in people who have never had it.

This is a live virus vaccine. It should not be given to people with weak immune systems, or to people with leukemia, lymphoma, or any cancer of the bone marrow or lymphatic system unless it’s treated and under control. It’s usually OK for household members of the person with weak immunity to get the varicella vaccine.

Talk to your doctor for more information or if you have questions.

If you’re exposed to chickenpox: A person with weak immunity who has been around someone with chickenpox should call the doctor right away.

Shingles (varicella-zoster) vaccine

This vaccine can help prevent shingles or make symptoms of shingles less severe. It does not contain a live virus.

The CDC recommends this vaccine for adults aged 50 and older, as well as for people 19 and over who have (or will have) weakened immune systems. People should get the shingles vaccine regardless of whether they’ve had chickenpox or shingles in the past.

(Chickenpox and shingles are caused by the same virus. Once a person recovers from chickenpox, the virus stays dormant (inactive) in the body. It can sometimes reactivate years later and cause shingles.)

If you have a weak immune system from cancer or cancer treatment, talk to your doctor about chickenpox and shingles vaccine options and whether one of these vaccines might be right for you.