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The answers are grouped in categories to make your search easier. For further information, please speak to a healthcare professional.

General Questions

  • What is the immune system?

    The immune system is a complex network of organs, cells and processes that defend the body against germs to help keep us healthy.

    If germs such as viruses or bacteria enter the body, there are specialised cells in our immune system that identify them and produce a response to fight the infection.

    The immune system can also ‘remember’ the attack from germs so it can fight them more easily the next time they enter the body.

  • How can I keep my immune system healthy?

    A healthy immune system is important to fight off germs, foreign substances and infectious diseases. There are several things you can do that can help to keep you healthy and reduce your risk of infection:

    • eat a balanced diet
    • stay active
    • get adequate sleep
    • quit smoking and reduce alcohol intake
    • manage stress
    • keep up to date with immunisations

    To learn more about each of these, please refer to the healthy aging section or speak to a healthcare professional.

  • What are infectious diseases?

    Infectious diseases are caused by germs such as viruses, bacteria or fungi. These germs can be harmless or under certain conditions, they may cause disease. The way infectious diseases are transmitted, their signs and symptoms, prevention and treatment options will vary depending on the type of germ.

    Practicing good hygiene can help to protect against illness and reduce the spread of germs. Good hygiene involves;

    • cover your mouth and nose when you cough or sneeze with a tissue or into your upper sleeve or elbow. Throw the tissue in the rubbish after using it.
    • wash your hands often with soap and water for at least 20 seconds
    • if no water is available use an alcohol-based hand-rub
    • avoid close contact with people who are sick
    • if you are sick, limit contact with others as much as possible to reduce the risk of infecting them
    • avoid touching your eyes, nose and mouth as this is how germs can spread
    • disinfect and clean objects and surfaces that may be contaminated.

    The risk of some infectious diseases may also be reduced through immunisation.

    For more information about infectious diseases please speak to a healthcare professional.

  • How do vaccines work?

    Vaccines work by teaching your immune system to fight future infections. Vaccines generally contain forms or specific parts of the germ that causes the disease, but because these elements of the germ are dead, inactivated or severely weakened, a vaccine cannot give you the disease.

    When the vaccine enters your body – either via a needle or oral dose – your immune system gets to work and produces specialised cells called ‘antibodies’ that are able lock onto and destroy the germ. Your immune system is then able to remember the germ and produce those antibodies to help destroy it if you are exposed to the disease again.

  • What are the common side effects of immunisations?

    You may experience some side effects after immunisation. Most are mild, short-lived and clear within a few days.

    Common side effects can include:

    • a sore arm
    • fever
    • pain and redness at the injection site
    • babies may be unsettled or sleepy

    Severe side effects like an allergic reaction are rare. If you think you or your child are experiencing a severe reaction, you should seek medical attention immediately.

    If you have any concerns about the side effects of immunisations, please speak to a healthcare professional.

  • Why immunise for less common or old diseases?

    Vaccines are given for potentially serious and fatal diseases, some that were common in Australia before immunisation was available. The germs that cause these diseases are still around however due to high rates of immunisation in Australia, most of these diseases are now fortunately very rare. In some countries however, there may be diseases that are more common and these could be brought back into Australia by travellers.

  • Can you still get a disease despite being immunised for it?

    Like all medicines, vaccines are not 100% effective. Therefore, there may still be a chance that an immunised person can get the disease – although usually with less severe symptoms than if they’d had no immunisation.

    The chances of exposure to some diseases are reduced in communities where most people are immunised, this is called ‘herd immunity’.

    For more information please speak to a healthcare professional.

  • What is the National Immunisation Program (NIP)?

    The NIP is a schedule of vaccines, from infancy through to adulthood, that are provided free of charge by the Australian Government.

    For more information please speak to a healthcare professional.

Pregnancy or Planning for a baby

  • Does my immune system change during pregnancy?

    During pregnancy, changes are made to your immune system so that it can create a balance to help protect the baby from infections without compromising your health; some parts of the immune system are heightened while other parts are suppressed.

    Since your body is supporting you and your baby it has to work harder, therefore these changes in the immune system may increase your susceptibility to certain infections.

    For more information, please speak to a healthcare professional.

  • How can I help keep healthy during pregnancy?

    There are several things you can do to help keep yourself and your unborn baby healthy during pregnancy. In general, these include good nutrition, food safety, exercise and avoiding alcohol and smoking. It is important that you speak with a healthcare professional about the ways you can help keep you and your baby healthy during pregnancy, and what may be right for you.

  • What diseases do I need to be aware of if I'm planning for pregnancy?

    During pregnancy some diseases can be harmful to you, your baby, or both of you such as rubella, mumps and whooping cough. You may already have immunity to some infectious diseases, but it is important to speak with a healthcare professional for more information if you are planning a pregnancy or soon after you find out you are pregnant.

  • I received certain immunisations during my pregnancy. Why does my baby need them too?

    When you are immunised, your antibodies transfer from you to your unborn baby. These antibodies help protect your baby for a short time after birth, when they are too young to be immunised themselves.  Therefore, immunisations after birth may help reduce your baby’s risks of certain infectious diseases.

Babies, toddlers & children

  • Are babies, toddlers and children’s immune system different to adults?

    A child’s immune system is not as well developed as an adult's. When a baby is born their immune system is not fully developed, making them more vulnerable to some infections and diseases. As they grow, they are naturally exposed to many different germs every day and this helps develop their immune system.

  • How can I help protect my baby, toddler and/or child from infectious diseases?

    During childhood there may be an increased risk of certain infectious diseases as the immune system is not fully developed.

    Below are some things you can do to help keep you and your child healthy:

    • practice good hygiene such as; washing hands frequently with soap and water for 20 seconds especially before eating, covering mouth and nose with a tissue or elbow when coughing or sneezing
    • avoid sharing food or utensils with others
    • stay at home when sick and keeping away from people who are sick
    • early recognition and treatment of infectious diseases
    • encourage a healthy diet
    • reduce the risk of some infectious diseases through immunisation

    Please speak to a healthcare professional for further information.

  • Do breastfed babies obtain immunity from breast milk?

    The antibodies in breast milk help fight off infection and provide some protection for your baby. However, they are short-lived and cannot help protect against all infections.

  • Can I delay immunisations until my child is older?

    Immunising your child at the ages and dosing schedule recommended by the National Immunisation Program can help protect them from potentially serious childhood diseases.

    Delaying an immunisation increases the amount of time your child does not have the immune response provided by a vaccine and therefore may be at higher risk of catching a disease if it was in the community.

    A scheduled immunisation may be delayed if your child:

    • has a high temperature (over 38.5ºC)
    • has a weakened immune system (e.g. receiving chemotherapy)
    • has received another immunisation or medication prior to the scheduled immunisation
    • has another medical condition that needs to be considered.

    For more information please speak with a healthcare professional.

  • Can too many immunisations overwhelm a baby’s immune system?

    From birth onwards, babies are naturally exposed to thousands of antigens a day. Antigens are substances that stimulate an immune response such as bacteria, viruses, chemicals and toxins. Children build up their exposure through things like playing, drinking and eating.

    Compared to this everyday exposure, immunisations contain a small amount of antigen. So rather than overwhelming the baby’s immune system, immunisations actually help strengthen it for specific diseases.

    Speak with your healthcare professional if you’re concerned about multiple immunisations.

  • Why do children need booster doses of some vaccines?

    With some diseases, the level of protection provided by an immunisation can decrease over time. Booster doses help maintain immunity over time.

    Please discuss your individual situation and any specific concerns with a healthcare professional.

Adolescents

  • How can adolescents help protect themselves from infectious diseases?

    Adolescents’ immune systems are more developed as they have built up immunity to certain infectious diseases through natural infection or immunisations.

    However, adolescents may be more susceptible to certain infectious diseases due to factors such as social behaviours and risk taking.

    Below are some things you can do to help stay healthy:

    • practice good hygiene such as; washing hands frequently with soap and water for 20 seconds especially before eating, covering mouth and nose with a tissue or elbow when coughing or sneezing
    • avoid sharing food or utensils with others
    • stay at home when sick and keeping away from people who are sick
    • early recognition and treatment of infectious diseases
    • encourage a healthy diet and exercise
    • reduce the risk of some infectious diseases through immunisation

    Please discuss your individual situation and any specific concerns with a healthcare professional.

  • Do adolescents need to start the schedule again if they missed any childhood immunisations?

    If your teenager did not receive some or all of the recommended doses of immunisations when they were young, they might need what’s called a ‘catch-up dose(s)’.

    Speak with a healthcare professional if you're unsure about your teenager's immunisation status.

Adults

  • What happens to the immune system as you age?

    As you age, your immune system function – the body’s natural defence against infectious diseases – starts to decline, particularly after the age of 50 years. The immune system may not work as well as it used to and can make you more susceptible to certain infectious diseases.

    Some of the following changes in the immune system may occur:

    • the immune system responds more slowly to germs, increasing the risk to certain infectious diseases
    • immune cells reduce in numbers, which means your body may take longer to heal
    • the immune system becomes less effective at detecting and correcting mutations in cells which may increase our risk of cancer
    • autoimmune disorders may develop as the immune system becomes less able to distinguish self from non-self, increasing risk of damage to healthy cells.
  • What can adults do to help maintain their immune system and help protect themselves from infectious diseases?

    These are some things (not a complete list) you can do to help maintain your immune system function and help promote healthy ageing over the long term:

    • eat a balanced diet
    • stay active
    • take steps to prevent infectious diseases
    • get adequate sleep
    • quit smoking and reduce alcohol intake
    • manage stress.

    Below are some things you can do to help stay healthy:

    • cover your mouth and nose when you cough or sneeze with a tissue or into your upper sleeve or elbow. Throw the tissue in the rubbish after using it.
    • wash your hands often with soap and water for at least 20 seconds
    • if no water is available use an alcohol-based hand-rub
    • avoid close contact with people who are sick
    • If you are sick, limit contact with others as much as possible to reduce the risk of infecting them
    • avoid touching your eyes, nose and mouth as this is how germs can spread
    • disinfect and clean objects and surfaces that may be contaminated.

    Please discuss your individual situation and any specific concerns with a healthcare professional.

  • How does a healthy diet promote a healthy immune system and healthy aging?

    A balanced and nutritious diet is essential for optimal functioning of all cells, including the cells of the immune system.

    You can incorporate healthy eating into your diet to promote healthy growth and maintenance of immune cells by:

    • take steps to avoid obesity. Obesity is associated with many health risks, including chronic inflammation, compromised immune function and increased risk of serious infection.
    • ensure you are eating enough food. Under-nutrition also compromises immune function by reducing the body's ability to fight off harmful pathogens.
    • certain micronutrients, vitamins and antioxidants, are important to support a healthy immune system. Some foods that are rich in micronutrients include leafy greens, brightly coloured fruit and vegetables, and nuts and seeds.

    Please discuss your individual situation and any specific concerns with a healthcare professional.

  • How much do adults need to exercise to maintain healthy immunity?

    Regular moderate-to-vigorous exercise can enhance immune defence activity, reduce chronic inflammation and help slow age-related decline in immune system function.

    Daily exercise recommendations:

    • Adults aged 18–64: aim for 2.5–5 hours of moderate intensity exercise, or 1.25–2.5 hours of intense exercise per week.
    • Adults aged 65+: try to get in 30 minutes of moderate intensity exercise most days.

    Please discuss your Individual situation and any specific concerns with a healthcare professional.

    Reference: 1. Department of Health. Australia’s physical activity and sedentary behaviour guidelines and the Australian 24-hour movement guidelines. 2019. Available at https://www.health.gov.au/health-topics/physical-activity-and-exercise/physical-activity-and-exercise-guidelines-for-all-australians (accessed June 2021)

  • How does smoking and alcohol consumption affect the immune system?

    Smoking and excessive alcohol consumption can trigger long-lasting inflammation, suppress immune function and increase risk of infection.

    • within 3 months of quitting smoking the immune system starts to recover
    • in healthy adults, it is recommended to limit alcohol consumption to fewer than 10 standard drinks a week, and no more than 4 on any one day. Older adults with existing health issues should follow advise from their healthcare professional. In general, the less you drink, the lower the risk of alcohol-induced harm to the body.

    Please discuss your individual situation and any specific concerns with a healthcare professional.

Travellers

  • I’m going overseas soon. Do I need to see my doctor?

    The risk of certain diseases may vary from country to country and within different parts of the same country, even in Australia. The more prepared you are, the safer and more enjoyable your overseas trip will be.

    It is important to plan ahead and see a healthcare professional at least 6 to 8 weeks before you travel to discuss prevention options and travel health. Take along your full itinerary so a healthcare professional can best assess your needs.

  • When travelling, can I eat the local food and is the water safe to drink?

    Some common diseases (such as hepatitis A, typhoid and traveller’s diarrhoea) can be caught if you consume contaminated water or food, or if you come into direct contact with an infected person. If you are travelling to a place with poor food hygiene, you should take care to avoid potentially contaminated food and water.

    Some recommendations include:

    • only drink and use safe, clean water (e.g. sealed bottled water or boiled water), even for things like brushing teeth
    • don’t put ice in drinks unless you know it’s from safe water
    • wash hands often using soap and safe, clean water for at least 20 seconds
    • avoid eating food kept at room temperature for several hours
    • avoid uncooked food, including salads and fruit that cannot be peeled, and seafood
    • thoroughly boil or cook food.

    An easy way to remember it: if you can’t boil it, cook it or peel it, forget it.

    To learn about diseases common in particular countries, you can browse our travel section. Please note that this is a guide only. Please discuss your individual situation and any specific concerns with a healthcare professional.

  • Why should I take anti-malarials if I’m taking measures to prevent mosquito bites?

    For travellers, most cases of malaria infection occur when medication is not taken as prescribed and measures to avoid mosquito bites (such as using repellents or insecticide-treated bed nets) have not been taken properly or at all.

    When anti-malarials are taken as recommended, and mosquito bite prevention measures are put in place, both the risk of contracting disease and the risk of serious disease is reduced.

    Please discuss your individual situation and any specific concerns with a healthcare professional.

PM-AU-AVX-WCNT-190029 Date of GSK Approval: July 2021