Increased risk of infection

Cancer or cancer treatments can reduce the number of white blood cells in your blood. With fewer white blood cells, your immune system cannot fight infections properly. 

What causes it?

White blood cell counts can be affected by:

  • Cancer that affects the blood or bone marrow, which produces white blood cells.
  • Cancer treatments like chemotherapy or other cancer drugs.

If your white blood cell count is low, you are more at risk of getting infections. Even minor infections such as a cold or sore throat could make you ill.

What are the symptoms of an infection?

Symptom of infection include:

  • A high temperature of 100.4°F (38°C) or more
  • A very low temperature of 35°C (95°F) or less
  • Feeling shivery or unwell
  • A new or worsening cough
  • A sore throat
  • Shortness of breath
  • Vomiting or diarrhoea

Ask your nurse about how to check your temperature and what to do if you feel unwell or have a high temperature.

You may be asked not to take paracetamol or other medicine while you are on treatment, as it could hide an infection.

What should I do if I have symptoms?

Always contact the hospital if you have a high temperature or other symptoms of infection. You will be given a special number. Contact the hospital straight away, even at night - don't delay.

Some hospitals prefer you to ring the ward directly. Check this with your nurse or doctor before you start treatment. 

How are infections treated?

If you have a high temperature or feel unwell, you will need to have a blood test to see if your white cells are low. You may also need antibiotics or other medication in hospital to treat the infection.

If you get an infection, an antibiotic will be given to bring it under control quickly. Intravenous antibiotics (antibiotics given into a vein) may be needed.

In special cases, you may be given antibiotics to prevent you from getting an infection or for emergency use. This may apply if you are at home or when travelling.

Drugs called growth factors can help your bone marrow to make more white blood cells quickly to prevent infection. These are given by injection under the skin (subcutaneously). A common one used to boost white cells is called G-CSF. 

If you get serious recurrent infections, your doctor may decide to give you immunoglobulins into your vein.

Tips to avoid infection

  • Avoid crowds.
  • Avoid close contact, such as hugging or kissing, with people who have colds or flu and other infections. This includes chickenpox, shingles or measles. Let your doctor know if you are in contact with these or any other infections.
  • Check with your doctor about which vaccinations are recommended for you and make sure you get them. 
  • Wash your hands often during the day, especially before you eat and after going to the toilet. You could also carry an antibacterial handrub to use when you’re out and about. 
  • Avoid unpasteurised milk, soft cheeses, undercooked meat and poultry, and the skin of raw vegetables and fresh fruit.
  • Avoid fast food or takeaway food.

Vaccinations

  • You will probably be advised to get the flu vaccine every year and the pneumonia vaccine every 5 years. 
  • Shingles (herpes zoster virus) can also be a common complication and you may be given anti-viral drugs to prevent this infection.
  • Some vaccines are not suitable if your immune system is low. For example live vaccines. So get advice from your doctor about which vaccines are helpful and safe for you.

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