Cancer drugs
Vaccination and immunisation are sometimes used to mean the same thing, but there is a slight difference. Vaccination is the physical act of having a vaccine, for example by injection. Immunisation is the process of your body developing immunity to a particular disease after a vaccine.
Vaccinations help prevent many infectious diseases. Your doctor may recommend you have certain vaccinations before, during or after your cancer treatment. They may also advise the people you live with to have some vaccines to reduce the risk of passing infections on to you.
There are some vaccinations you shouldn't have when you have low immunity because they could make you very ill. You might also need to avoid contact with other people who have had certain types of vaccinations.
Cancer treatment can affect how the produces . This can weaken your , making it harder to fight infectious diseases.
Treatments that can affect the immune system include:
some types of drugs
some
long term
removal of the
a
The effect of treatment on your immune system can also depend on:
the cancer drug
the amount (dose) of the drug or radiotherapy treatment
if you are having more than one treatment at the same time
Find out more about the different types of cancer treatment
There are two main types of vaccines:
live vaccines
non-live vaccines
Live vaccines contain a weakened form of the disease they protect against. Non-live vaccines contain a killed version of the virus.
You shouldn't have live vaccines during treatment and for some months afterwards. For some types of cancer, such as or chronic lymphocytic leukaemia, you usually need to avoid live vaccinations for life.
People with cancer can usually have vaccines that are not live. But if you have a weakened immune system the vaccine may not work as well. Your doctor will talk to you about the best time to have the vaccine during your treatment.
The flu vaccine helps to prevent infection from the influenza virus. Every autumn, there is a national immunisation programme that invites people who would benefit from the flu vaccine.
Doctors encourage adults with cancer to have the flu vaccine if they are having cancer treatment. The vaccine for adults is by injection. This is a non-live vaccine. Ask your doctor about the best time to have this. This will depend on your situation and the type of treatment you are having.
Children can also have the flu vaccine as part of the immunisation programme. They usually have it as a nasal spray. This contains a live but weakened form of the flu virus. If your child has cancer, talk to their healthcare team. The doctor may recommend that your child doesn’t have the nasal spray if they have a very weakened immune system. In this situation, your child might have the flu vaccine injection instead.
If your immune system is severely weakened, for example after having a stem cell transplant, you should avoid close contact with children who have had the nasal spray flu vaccine. This is for about 2 weeks after they had the vaccine. This is because there is a very small chance that the vaccine virus could be passed on to you and cause illness.
The flu vaccine injection does not contain a live virus, so you don’t need to avoid contact with people who have had the injection. So if you live with children and you have a weakened immune system, your doctor will advise that they have the flu vaccine as an injection.
Check with your doctor if you are unsure whether your cancer or its treatment has severely weakened your immune system.
Find out more about the flu vaccine and cancer treatment
COVID-19 is caused by a type of coronavirus. The virus commonly affects your breathing or respiratory system. But it can affect other parts of the body.
COVID-19 is very infectious and some people with cancer are at a higher risk of developing severe COVID because they have a weakened immune system.
Every year, in the spring and the autumn, the Government makes recommendations about who should receive the coronavirus vaccine. This includes all people who have a weakened immune system due to their cancer or cancer treatment. The vaccine is not live. Your doctor can tell you the best time to have it.
Read more about the coronavirus vaccines
Babies have a vaccine at 8 and 12 weeks old called the rotavirus vaccine. Rotavirus causes sickness and diarrhoea. The vaccine contains a very weakened form of the rotavirus. The baby swallows the vaccine, and rotavirus passes out in their poo for about 2 weeks afterwards.
This vaccine could pose a risk to you if your immunity is low. There is a small risk you could catch the rotavirus infection.
There is no need to avoid all contact with a recently vaccinated baby. Ask someone else to change their nappies during this time if you can. If this isn't possible, wash your hands well after changing their nappy.
There is a far greater risk to a person having cancer treatment if they share a house with a baby that hasn’t had the rotavirus vaccine. The baby is more likely to pick up the virus from other babies and children, which is much more infectious.
The pneumococcal vaccine is not a live vaccine. It protects against pneumococcal infections. These infections could lead to illnesses such as:
an infection of the lung (pneumonia)
blood poisoning (septicaemia)
an infection of the protective membranes surrounding the brain and spinal cord (meningitis)
The pneumococcal vaccine is part of the routine vaccination programme, so children have it at 16 weeks and 1 year of age. Adults have it once at 65 years of age or older. People in certain risk groups may also have the vaccine.
Your doctor might suggest you have the pneumococcal vaccine if your immunity is low. For example, if you have:
acute or chronic leukaemia
myeloma
no spleen or it’s not working properly
had a stem cell transplant
You may have the vaccine before you start treatment, if there is time. Or you have it a number of months after you have finished treatment.
You have the pneumococcal vaccine every 5 years if you have had your spleen removed or your spleen is not working well.
Some cancers and cancer treatments can cause chronic kidney disease (CKD). CKD can affect your immune system. Some people with CKD have the pneumococcal vaccine every 5 years.
The varicella zoster virus causes chickenpox and shingles. After having chickenpox the virus remains inactive in the body, hiding in the nerves. Years later the virus can become active again and cause shingles. People with a weakened immune system are at higher risk of developing severe shingles.
You can’t catch shingles from someone else, but the virus can spread and cause chickenpox in someone who has never had it. People with a weakened immune system are more at risk of serious complications from chickenpox or shingles.
Chickenpox vaccines are live vaccines made from a weakened form of the live virus.
As of 1st January 2026, children have the chickenpox vaccine as part of the NHS childhood vaccination programme. It is combined with the measles, mumps and rubella (MMR) vaccine. This is called the MMRV vaccine. It stands for measles, mumps, rubella and varicella.
There are also individual chickenpox vaccines available outside of the childhood immunisation programme.
You shouldn’t have the chickenpox vaccine if you have a weakened immune system as it is a live vaccine. Your doctor may recommend you have the vaccine before you start cancer treatment if you have never had chickenpox before.
Your doctor may advise the people you live with or those you have regular close contact with to have the vaccine if they haven’t had chickenpox. This is so they cannot develop chickenpox and pass it on to you.
Some people may develop a chickenpox-like rash up to a month after having the vaccine. If this happens, there is a risk that they could pass on the vaccine virus to someone with a weakened immune system. But this risk is very low.
If someone develops a rash after the vaccine, they should cover it with clothing to reduce the risk of passing on the vaccine virus. They should see their GP to check if the rash is due to the vaccine virus or if they happened to catch chickenpox before they had the vaccine. They should keep the rash covered until it becomes dry and crusted, or there are no new signs of a rash for 24 hours.
Contact your advice line if you have been in close contact with someone who has developed a rash after the vaccine.
The shingles vaccine helps to prevent shingles or makes the symptoms from it less severe. The vaccine is part of the national immunisation programme for older people.
Anyone aged 18 and over can have the shingles vaccine if they have a very weakened immune system. For example, if you have had:
chemotherapy or radiotherapy in the last 6 months
a stem cell transplant in the last 2 years
a stem cell transplant more than 2 years ago but have
high dose steroids for more than 10 days in the past month
The shingles vaccine is not a live vaccine. You usually have two doses between 2 and 6 months apart.
Your doctor will let you know if you should have the vaccine and when the best time is to have it.
The respiratory syncytial virus commonly causes infections of the breathing system. It is a very common cause of coughs and colds. It is easily passed on through the air by sneezing and coughing.
Most people can clear this virus on its own, but some people can get quite sick from it. These are usually the elderly, children under a year and people with a weakened immune system.
There is now an RSV immunisation programme to help prevent RSV in those most at risk. This includes:
adults aged 75 years or older
adults aged 65 years to 74 years who have a weakened immune system (this is available from September 2026)
The RSV vaccine is not a live vaccine.
Measles is a very infectious disease that is easily spread from an infected person through breathing, coughing and sneezing. Or it can be passed on by droplets from something that has been contaminated or touched by someone who is infected.
The measles vaccine is part of the routine childhood immunisation programme. There is a:
3 in 1 vaccine against measles, mumps, and rubella (MMR)
4 in 1 vaccine against measles, mumps, rubella and varicella (MMRV)
These are live vaccines.
You cannot have the MMR or MMRV vaccine if you have a severely weakened immune system.
If you have a weakened immune system, your doctor may recommend that the people you live with have the MMR or MMRV vaccine if they have not had it before. This is to help protect you from these infections.
It is usually safe to be around anyone who has recently had the MMR or MMRV vaccine. But you may need to avoid close contact with someone who has developed a chickenpox-like rash after the MMRV vaccine - see information above about the chickenpox vaccine.
You should avoid contact with anyone who has or thinks they have measles if you have a weakened immune system. It can make you very unwell.
It is important that you tell your healthcare team straight away if you think you have been in contact with someone with measles. They will check if you have it and if you need treatment. People with measles are infectious from about 4 days before the rash appears to 4 full days after they develop the rash.
Meningitis is inflammation of the membrane (meninges) that supports and protects the brain and .
Meningitis is spread from an infected person through breathing, coughing and sneezing. It is very serious and can lead to sepsis or blood poisoning (septicaemia).
Meningitis commonly affects babies, children, teenagers and young people. The meningitis vaccines help prevent or lesson the severity of meningitis. They are included inthe national immunisation programme.
There are two types of vaccines which contain different strains of meningitis causing bacteria. They are MenACWY and MenB. Babies have the MenB vaccine at 8, 12 and 52 weeks of age. Teenagers have the MenACWY at around the age of 14 years. These are not live vaccines.
Doctors usually recommend that people who have no spleen or their spleen isn’t working well have the meningitis vaccines. Your doctor can tell you which vaccine to have and when to have it.
Some people may need to repeat the vaccinations they had as a child. This is because you can lose your immunity to illnesses you have been vaccinated against in the past if you have either:
a stem cell transplant
CAR T-cell therapy
At the end of your treatment, your doctor or nurse will talk to you about what vaccinations you may be due and when you can have them.
You can’t have live vaccines until your immune system is working properly. So this means you may need to avoid live vaccines for 6 to 12 months or longer.
The timing of when these vaccinations start depends on the type of treatment you have had. It also depends if you have any side effects from your treatment such as graft versus host disease. It can also vary slightly between hospitals. Your transplant team will let you know.
You might need to have other vaccinations if you are travelling abroad. Some of these are live vaccines. Talk to your healthcare team about this before you have any vaccines.
Find out about travel vaccines
Your pet also follows a vaccination schedule to help prevent them from getting certain diseases. Some of these vaccines are live vaccines.
Most pet vaccines are specific to the animal and not a risk to humans. But there is a very small risk that the live vaccine for kennel cough in dogs could cause a breathing illness in people with a severely weakened immune system. This live vaccine is usually a nasal spray.
Talk to your vet if your pet is due the live vaccine and you are having treatment for cancer. They may be able to give a different vaccine by injection instead. Or they may suggest checking your dog’s immunity with a blood test to see if they can avoid having the vaccine.
They can tell you if you need to take any precautions after the kennel cough vaccine, such as:
not being in the room when your dog has the vaccine
not touching secretions from your dog’s nose or mouth
washing your hands well after touching your dog
It’s important your pet still has its vaccines as usual. The risk to you from a live vaccine if you have a weakened immune system is usually much less than if your pet had the illness the vaccine is designed to protect against.
Talk to your cancer doctor, pharmacist or specialist nurse if you’re not sure how much your treatment will affect your immune system. They can also give you general advice about taking care of pets when you have a weakened immune system.
Last reviewed: 22 Jul 2026
Next review due: 22 Jul 2029
Cancer or its treatment can lower your resistance to infection and make you more likely to catch flu. The flu vaccination makes it less likely that you will catch flu.
COVID-19 is an infectious illness caused by a type of coronavirus. Some people with cancer are at a higher risk of complications because they have a weakened immune system.
Treatments can include surgery, radiotherapy and drug treatments (such as chemotherapy, hormone therapy or targeted cancer drugs). Find out about treatments and how to cope with side effects.
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