Managing your infection risk

Blood cancer and its treatment can stop your bone marrow making enough healthy white blood cells. These are an important part of your immune system. They usually make antibodies and fight infections.

If you do not have enough healthy white blood cells, you might:

• Be unable to fight off germs that are usually harmless.
• Have infections that wouldn’t be of notice to, or affect, other people. These can be more severe, last longer, or be more difficult to get rid of.
• Be more likely to develop serious infections, such as sepsis.

You may hear people call this immunosuppression, immunodeficiency or immunocompromise.

The types of infection most likely to affect you include:

• Bacterial infections. Bacteria can cause infections of your skin, blood, lungs and other organs and body parts. They include urinary tract infections (UTIs), sinus and ear infections, and food poisoning. Plus, sexually transmitted infections (STIs), like chlamydia and gonorrhoea.
• Viral infections. Viruses cause common infections, like colds, flu, respiratory syncytial virus (RSV), and COVID-19. They also cause the winter vomiting bug (norovirus), chickenpox, and warts. Some viral infections already in your body can re-emerge and cause you problems. These include cold sores, genital herpes, hepatitis and shingles.
• Fungal infections. Yeast and moulds can cause infections of your skin, nails, mouth, and genitals. They can also get into your bloodstream and organs. This is called an invasive fungal infection. They include candidiasis from the yeast Candida, which also causes thrush. Plus, aspergillosis, which is caused by the mould Aspergillus.

You may be more likely to get some types of infection than others, depending on which blood cancer you have. Some treatments for blood cancer can also increase your risk of some infections as a side effect.

Your haematology team or GP can tell you which infections to look out for and how to try to prevent them.

Many treatments for blood cancer lower your immune system, including:

• Antibody therapy
• Targeted treatment
• Chemotherapy
• Intensive treatment, like CAR T-cell therapy and stem cell transplants

These treatments may suppress your immune system during and after treatment. Sometimes, your immune system can be weak for a long time after treatment. It depends on the treatment you’ve had.

If you have blood cancer, infections that may be mild and short-lived in other people can be more serious. As well as the impact on your health and wellbeing, infections can lead to other consequences.

• Some infections can be very uncomfortable and painful.
• Some infections can worsen fatigue.
• Some infections can give you a sore mouth and make eating difficult. This may lead you to become underweight.
• Severe or long-lasting chest infections can damage your lungs. This can make you more vulnerable to other problems.
• Infections can make you more likely to need help from your GP and local hospital. You’re more likely to need treatments, like antibiotics.
• If you’re due to start intensive treatment and you’ve got an infection, you may have to delay it. If you go ahead with an intensive treatment while you’re unwell, you could become seriously ill. With some infections and treatments, it’s safer to wait until you’re better. This includes treatments like chemotherapy, stem cell transplant or CAR T-cell therapy.

If you’re having treatment and get an infection, it may affect your recovery. You may take longer to get better and need a longer hospital stay.

If possible, ask someone else to clean out the cat litter tray or clean up after your dog or other animals. If you do clean up after your pet, wear gloves and wash your hands afterwards.

Be careful gardening where cats, foxes, rodents, birds and other animals may have had a poo or a pee. Wear shoes and gardening gloves and wash your hands afterwards. You may consider wearing a face mask while you’re gardening too.

Stay away from people who have infections. You may choose to avoid crowded, unventilated places where infections can spread easily.

If you’re in work or education, inform your workplace, college or university. Tell them that you need help to avoid infections. Ask if you can work from home or log into large in-person meetings online.

Avoid busy GP or hospital waiting rooms, if you can. If possible, ask for an online or telephone medical appointment rather than an in-person one. If you have a face-to-face appointment, tell the receptionist that you’re at risk of infection. Ask if you can wait in a separate space away from other people and consider wearing a face mask and using hand sanitiser.

You may want to be particularly careful in the colder months. Over the winter, flu-like illnesses are more common. In the warmer months, you’re more likely to get a cold. But it may also be easier to ventilate indoor spaces or to socialise outside.

Cuts and grazes can let germs into your body. To prevent them:

• Wear protective clothing, shoes and gloves when you’re gardening
• If you shave, consider swapping from a razor to an electric shaver

If you have a cut or graze, keep it clean and wash your hands before and after treating it.

Some holiday destinations carry a greater risk of infection from food, water and insect bites than others. Some require you to have travel vaccinations, such as Yellow fever, that may not be safe for you.

Consider using a saline nasal spray or an anti-viral nasal spray if you get recurrent colds and flu-like illnesses. Using a nasal spray at key times may lower your chance of catching a cold or flu-like infection. Or make an infection milder and shorter if you catch one.

You might use a nasal spray at the first sign of a cold. Or when you’ve shared a space with someone who has, or may have, a cold, flu or COVID-19.

Talk to your haematology team or GP about whether nasal sprays are suitable for you, and when and how to use them.

Sometimes you can’t avoid going out when it's busy or doing activities that may affect your lungs. There’s not much evidence that face masks make a big difference to your risk of getting an infection. But using a face mask may give you confidence to get on with your life. Or you may want to wear one just in case.

Consider wearing a good-quality mask if:

• You’re going to a crowded place or somewhere with low ventilation.
• You’re going to your GP surgery or hospital and may have to wait in a busy waiting room.
• You’re gardening, particularly if you’re working with compost or other natural fertilisers. Also, when you’re cutting back plants or handling garden waste that may contain spores.

Use a mask that fits your face well and offers you good protection, such as an FFP2 or FFP3 mask.

Eat a healthy, balanced diet to help your body work well and support your immune system. Avoid drinking alcohol, as it can weaken your immune system.

Your haematology team will recommend you have non-live vaccinations that you’re eligible for. Encourage people you live with to have non-live vaccinations they’re eligible for, too.

You may also need travel vaccinations if you’re going on holiday abroad.

Find out more about vaccinations and when to have them.

Move your body to help it work well and to support your immune system. Keeping active can improve your quality of life and reduce fatigue. It may also result in fewer colds and other flu-like illnesses.

Brush your teeth twice a day:

• Use a manual or electric toothbrush to clean every surface of your teeth.
• Use floss or interdental brushes to shift trapped food from between your teeth. This helps reduce tooth decay and keep your gums healthy.
• If you wear removable dentures or similar, brush them with cleaning agents made for this job. Or use an ultrasonic cleaner.
• If you’ve got dental implants, take special care of the teeth next to your implants.

Go to your dentist for regular check-ups. Always remind them about your condition, any treatments you’re on, and how they may affect you.

Your haematology team may give you special dental advice at certain points:

• If your blood counts are low, they may recommend swapping to a soft or very soft toothbrush. They may also tell you not to clean between your teeth with floss or interdental brushes. But if you’re already used to doing this without injuring your gums, you can usually carry on. Check with your haematology team.
• If you’re due to have intensive treatment, have a dental check-up beforehand. This includes treatments like chemotherapy, a stem cell transplant or CAR T-cell therapy. If you need it, have dental treatment before you start treatment.
• If you’re at risk of mouth infections, they may suggest using a chlorhexidine mouthwash. There are alcohol-free versions that may suit you better if you have sensitive gums.

If you’ve got fatigue, try your best to look after your teeth and gums every day. Even when you don’t feel like it. You may save yourself from problems with your teeth or gums later.

Stress management can help you live well and support your immune system. It can help you take control of your situation.

Try to build your resilience and emotional strength. Avoid reaching for unhealthy ways of coping, like smoking and drinking alcohol. Both of which can weaken your immune system.

Talk to your haematology team or GP if you need emotional support. They may be able to refer you to a psychologist or a counsellor.

Smoking can put extra strain on your immune system. Many people switch to vaping to help them stop smoking. Although there are benefits in vaping compared to smoking, using vapes can also weaken your immune system.

If you smoke or vape, consider using an NHS stop smoking service to help you quit. These are local services staffed by expert advisors. They can help you find a way of quitting that suits you and protects your immune system.

Take care to store, prepare and cook food carefully. This will reduce your risk of food poisoning or food-borne infections. Simple things you can do to reduce the risk include:

• Washing your hands before preparing or eating food
• Keeping kitchen surfaces and utensils clean
• Following guidance carefully for:
  • Use-by dates
  • Preparing and storing food
  • Chilling, freezing and defrosting food
  • Cooking and reheating food

The Food Standards Agency has more information on storing food and cooking it safely. They also have information on food hygiene ratings if you like to eat out or get takeaways.

It’s important to keep your hands and body clean to reduce contact with and buildup of germs:

• Wash and dry your hands throughout the day, particularly:
  • After close contact with people and animals
  • After touching handles, surfaces and other objects used by other people
  • After going to the toilet
  • Before preparing or eating food
• Use an alcohol-based hand sanitiser if you can’t wash your hands
• Wash your genitals and bottom every day and have a bath or shower at least twice a week
• Keep your feet clean and dry:
  • Wear clean socks every day
  • Wear sliders or flip flops at the gym or swimming pool
  • Avoid shoes that make your feet hot and sweaty
• Keep your nails short
• Do not share towels or nail clippers with other people

If you care for someone with blood cancer, find out more about helping someone to keep clean.

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