Avoiding infection when you have reduced immunity

Transcription

1 This information is for people who have reduced immunity because of the effects of cancer or its treatment. It explains how to avoid infection when your immunity is low. In this information: The immune system Cancer, its treatment and the immune system Things you can do References and thanks The immune system Your immune system is your body s defence against bacteria, viruses and other foreign organisms or harmful chemicals. It has to work properly to protect you from harmful bacteria and other organisms in the environment. Your immune system has three parts: the skin and mucosal membranes soluble proteins produced by the body, which are present in body fluids blood and lymph cells. The skin and mucosal membranes Your skin and the lining of the body cavities that open to the outside, such as the gut and the reproductive tract, are protective barriers. They stop harmful organisms getting in to your body. Your skin produces an oil which keeps it slightly acidic. This controls the growth of any harmful organisms on your skin. Cells which line your body cavities produce fluids, such as saliva in the digestive system and mucus in the lungs. These help your body to destroy harmful organisms. Your body also has its own natural and helpful organisms that prevent more harmful organisms from taking over. Proteins Special proteins and chemicals are present in the secretions and fluids that your body produces. If organisms do manage to enter your body, the proteins attack them in various ways, often by dissolving them. Page 1 of 7

2 Blood and lymph cells Blood and lymph cells are produced by your bone marrow and your lymphatic system. Your bone marrow is the spongy cells in the middle of some of your bones. Your lymphatic system is a complex system made up of organs such as bone marrow, the thymus, the spleen and lymph nodes. Lymph nodes are found throughout your body and are connected by a network of tiny lymphatic vessels. Neck (cervical) lymph nodes Thymus Armpit (axillary) lymph nodes Diaphragm Spleen Groin (inguinal) lymph nodes The lymphatic system Different types of white blood cells play varying roles in destroying organisms that invade the body. They travel through your blood vessels or lymphatic vessels to the site of damage or infection, and destroy the harmful organisms. Cancer, its treatment and the immune system Cancer and its treatment can affect your immune system in a number of ways. The type of cancer you have Some cancers, particularly lymphomas and leukaemias, may lower the effectiveness of your body s natural immune defences. They do this by preventing your bone marrow from producing enough healthy white blood cells. Page 2 of 7

3 Surgery Surgery can make you more prone to infection because it involves making a break in the skin or mucous membranes, which are part of your body s natural defences. You are more likely to get an infection if you have an operation to remove your spleen. The spleen is an important part of the immune system. Removing it will mean you have permanently reduced immunity. You will need to take antibiotics to protect yourself from infection (called prophylactic antibiotics). Radiotherapy This often has a mild and temporary effect on your immune system. It is unlikely to cause any problems unless you have radiotherapy to your whole body (total body irradiation). During total body irradiation, all the bone marrow in your body receives a dose of radiation. This temporarily lowers the production of white blood cells, so you will be at risk of infection for a while. Chemotherapy This can often have a major effect on your immune system. It may reduce your body s defences against infection both during and after treatment. This is because chemotherapy reduces the number of white blood cells produced by the bone marrow. You are particularly at risk of picking up infections 7 14 days after your chemotherapy, when the level of white blood cells is at its lowest. This time is known as the nadir, and it can vary slightly depending on the chemotherapy drug or combination of drugs used. Infections can usually be effectively treated with antibiotics. If an infection is not treated quickly, it can be much more difficult to it get under control. Contact the hospital straight away on the contact number you ve been given if: your temperature goes over 37.5 C (99.5 F) or over 38 C (100.4 F), depending on the advice given by your chemotherapy team you suddenly feel unwell, even with a normal temperature you have symptoms of an infection this can include feeling shaky, a sore throat, a cough, diarrhoea or needing to pass urine a lot. These are signs of a possible infection and you may need to have antibiotic treatment, either as tablets or by drip (intravenous injection). Page 3 of 7

4 Things you can do There are a number of things you can do to reduce your risk of getting an infection when your immunity is reduced. Avoiding infection When your immunity is reduced for any reason, it s best to avoid other people who have sore throats, colds, flu, diarrhoea and vomiting, or other kinds of infection such as chickenpox. If you do come in contact with anyone who has an obvious infection, ask your hospital doctor or specialist nurse for advice as soon as possible. You may need to have medicines to prevent you from getting the infection. It s important to go outside to get some exercise and fresh air during or after cancer treatment, but it s best to avoid crowds where possible. This includes: avoiding using public transport, particularly during the rush hour, and crowded shopping centres where you may be mingling with people who have infections that are not obvious. It s best to avoid swimming or using a public jacuzzi when your immunity is reduced because there s a risk of picking up an infection from the water or in the changing room. Again, avoid crowds when doing other sports or social activities. If you have pets or work with animals, you ll need to be extra careful. It s usually safe to pet or stroke animals as long as you wash your hands thoroughly afterwards. However, it s best to avoid handling any animal waste, such as litter trays or manure, since this can increase your chances of getting an infection. If you aim to continue working during your treatment, it s a good idea to talk to your employer or human resources department. They should be able to offer you support and look at ways to help you avoid getting an infection. You may be able to work part-time or work from home during the times when your immunity is reduced. While you have reduced immunity, you should be careful to avoid places where a mould/ fungus, called aspergillus, is likely to be. Aspergillus can grow in dead leaves, grain stores, compost piles or other decaying vegetation. It may also be found in building materials such as brick, mortar and cement dust, so places, such as building sites, may contain this fungus. Vaccinations It s always best to discuss any planned vaccinations with your consultant or specialist nurse. It s safe to have a flu jab when your immunity is reduced. The flu jab is an inactivated vaccine, which means that it can t harm you. But, depending on the type of cancer and treatment you ve had, the vaccine may not give you quite as much protection against flu as in previous years. Generally, people with cancer are recommended to have the vaccine at least two weeks before starting treatment or between their chemotherapy cycles, and then yearly. If you re planning a holiday abroad and need to get vaccinated before you go, check with your GP, consultant or specialist nurse first. Some vaccines, known as live attenuated vaccines, should be avoided. These include measles, mumps, rubella and MMR, oral poliomyelitis liquid, oral typhoid, BCG and yellow fever. Page 4 of 7

5 If you have reduced immunity, your family and friends should also avoid having the oral typhoid vaccination. Some vaccines, such as poliomyelitis, can be given in an inactivated form. Hygiene One of the most effective ways of avoiding infection is to maintain a high standard of personal hygiene. It s important to remember to always wash your hands when you have been to the toilet, and before you are about to prepare or eat food. It s also a good idea to take a daily shower or bath, if possible. It s best not to share towels or flannels with other family members because of the possible risk of cross-infection. Central lines and PICC lines Some people receiving cancer treatment have central lines or PICC lines. These are long, hollow tubes made of silicone rubber. They are also called tunnelled central venous catheters. A central line is inserted (tunnelled) under the skin of your chest into a vein. The tip of the tube sits in a large vein just above your heart. A PICC line is inserted into one of the large veins of the arm near the bend of your elbow. It is then pushed into the vein until the tip sits in a large vein just above your heart. A central line or PICC line can stay in place for many months. If you have one, you will need to protect it from infections and possible damage. Your hospital or district nurse will give you advice about how to keep it clean. A transparent dressing is often used and can be changed weekly. You will be able to have a bath or shower. Mouth care You can develop a mouth infection when your immunity is low. You ll need to take extra care to keep your mouth clean. Use a soft-bristle toothbrush that isn t too abrasive. A hard one might cause your gums to bleed, which can increase the risk of infection. Your doctor may prescribe antiseptic mouthwashes for you to use after meals and at night. They may also prescribe antifungal mouthwashes or lozenges. Used regularly, these can help prevent infection from developing. Because of your risk of infection, it s important to discuss any dental work you need to have done with your cancer specialist first. Page 5 of 7

6 Eating and drinking Drinking plenty of fluids can help prevent infection. Fluids help keep your mouth moist and healthy. It will also flush out your kidneys and bladder, which prevents the build-up of debris where bacteria can grow. It s thought that drinks such as cranberry juice may also help reduce the risk of developing urinary infections. For various reasons, people often find it difficult to eat and drink when they have cancer. This may be due to the cancer itself or the side effects of treatment. For example, you may feel sick (nausea), or have taste changes that affect your appetite. However, it s important to try to eat a healthy and balanced diet as this will help maintain your immune system. Some foods can have harmful bacteria in them, especially shellfish, poultry and eggs. These bacteria are usually killed by heat or made less harmful by cold. It s important to ensure that all food is stored at the correct temperature and cooked thoroughly. It s also important not to reheat food that has cooled, as this may allow bacteria to grow. You doctor or specialist nurse may recommend that you follow a clean diet. This means avoiding salads that could be dirty and foods that could contain harmful bacteria. These include: raw or lightly cooked eggs shellfish all types of pâté soft cheeses takeaway food pre-wrapped sandwiches cooked sliced meats smoked fish. Advice on following a clean diet will vary depending on the type of cancer you have and the treatment you are receiving. For example, the guidelines might be very strict if you have leukaemia and are having high doses of chemotherapy, or if you have had high-dose treatment with stem cell support. It s best to always check your diet with the hospital staff caring for you. Your food needs to be carefully prepared so that infection can t pass from one food to another. All food should be used before its use by date. Care should be taken to keep raw and cooked foods apart. It s also important to keep clean foods away from potentially dirty foods, such as those mentioned above. Try to eat a variety of food as much as possible. Also try to eat the recommended five helpings of fruit and vegetables every day. These contain essential vitamins and minerals, which will help keep you healthy. Wash fruit and vegetables thoroughly and peel before use. You may find it best to eat fruits that are easy to peel, such as bananas and oranges. You could also juice them and make fresh fruit juice to drink. Page 6 of 7

7 References and thanks The information in this section has been produced in accordance with the following sources and guidelines: Souhami, Hochhaser. Cancer and its management. 6th edition Wiley-Blackwell. Dougherty et al. The Royal Marsden Hospital Manual of Clinical Nursing Procedures. Eighth edition Wiley - Blackwell If you d like further information on the sources we use, please feel free to contact us. Thanks With thanks to Natalie Singer, Haematology Nurse Practitioner, who reviewed this edition. Thank you to all of the people affected by cancer who reviewed what you re reading and have helped our information to grow. You could help us too when you join our Cancer Voices Network - find out more. Content last reviewed: 1 August 2014 Next planned review: 2016 We make every effort to ensure that the information we provide is accurate and up-to-date but it should not be relied upon as a substitute for specialist professional advice tailored to your situation. So far as is permitted by law, Macmillan does not accept liability in relation to the use of any information contained in this publication or third party information or websites included or referred to in it. Macmillan Cancer Support, registered charity in England and Wales (261017), Scotland (SC039907) and the Isle of Man (604). A company limited by guarantee, registered in England and Wales company number Isle of Man company number 4694F. Registered office: 89 Albert Embankment, London SE1 7UQ. For cancer support every step of the way, call Macmillan free on (Mon-Fri, 9am-8pm) or visit macmillan.org.uk Page 7 of 7