Tuberculosis (TB)
Key facts
- Tuberculosis (TB) is an infectious disease caused by bacteria that can affect any part of your body, most commonly your lungs.
- TB can be latent (where you don’t have any symptoms and aren’t infectious) or active (where you are unwell and may spread the infection).
- A tuberculin skin test (Mantoux test) or a blood test can check if you have been infected with TB.
- TB is treated with a combination of antibiotics, which you will need to take for at least 6 months.
- The BCG vaccine may help prevent severe illness from TB, but in Australia, it is only recommended for people at high risk of exposure.
What is tuberculosis?
Tuberculosis (TB) is an infectious disease caused by the bacterium mycobacterium tuberculosis. It most often affects your lungs but can affect any part of the body. If not diagnosed and treated, it can lead to serious illness and death.
There is a difference between TB infection and TB disease:
- Latent TB infection — is when a person is infected with TB but does not get sick. This is because their immune system controls the infection. The immune system surrounds the bacteria after entering the body. It creates a barrier that keeps the bacteria asleep for years. There is a risk that latent TB can become active later on. People with latent TB can’t spread the disease to others.
- Active TB disease — is when the TB bacteria multiply and the immune system can’t control them. This leads to symptoms. People with Active TB can spread the disease to others.
Most people with latent TB never become unwell. About 1 in 10 people will develop active TB. This may happen shortly after infection or many years later. Young children, older people and people with weakened immune systems are more likely to become unwell.
It’s rare to catch TB in Australia. In Australia, most TB infections happen in people who are born in countries where TB is common. TB is common in many other parts of the world.
What are the symptoms of tuberculosis?
If you have a latent TB infection you will not have any symptoms.
In most infected people TB mainly affects the lungs, although it can affect almost all other organs. If you have lung TB you may have symptoms, such as:
- a cough that lasts at least 3 weeks
- shortness of breath
- sputum (phlegm) containing blood
- chest pain
People with TB disease may also:
- feel tired
- lose weight without trying to
- have a fever
- sweat in bed at night
- lose their appetite
TB in other parts of your body may lead to pain or swelling in that area. Lymph node TB can lead to swollen glands.
CHECK YOUR SYMPTOMS — Use the Symptom Checker and find out if you need to seek medical help.
What causes tuberculosis?
TB is caused by the bacterium mycobacterium tuberculosis. The bacteria spreads through the air when a person with active TB in their lungs or throat:
- coughs
- sneezes
- speaks
If people nearby breathe in the bacteria, they can get TB. If their immune system can control the bacteria, they will have a latent infection. If their immune system can’t control the bacteria, they will have active TB disease.
People with active TB in other parts of their body are not infectious. Latent TB is also not infectious.
Am I at risk of getting tuberculosis?
Most healthy people can control the bacteria and develop latent TB. You are at higher risk of catching TB if you:
- have had close contact with someone with active TB — the longer, more often or more closely you were in contact, the higher your risk
- live in a country where TB is common
- have a weakened immune system — from a chronic condition or medicines
When should I see my doctor?
See your doctor if you have symptoms of TB or if you have been exposed to someone who is infectious. Your doctor can refer you for testing.
If you are a refugee, see a doctor and get tested for TB test soon after you arrive in Australia.
You may also need a TB test if you:
- have moved to Australia from a country where TB is common
- start a medicine that weakens your immune system
- live in crowded surroundings
- work with people who may have TB
- work in the healthcare system
- inject drugs
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How is tuberculosis diagnosed?
Your doctor may order a tuberculosis screening test to check if you have been exposed to the bacteria. There are different types of tests that look at how your immune system responds to the bacterium.
- Tuberculin skin test (Mantoux test) — a small amount of liquid is injected just under the skin of your forearm. A healthcare worker will check the area 48 to 72 hours later. A lump will appear on your skin and will be measured. Positive results depend on the size of the lump.
- QuantiFERON Gold test — a blood test measures how your immune system responds to the bacterium.
These tests can’t tell you if you have active or latent TB.
If your test is positive, your doctor may do more tests to check if you have active TB, such as a:
- chest x-ray
- physical examination
- sputum culture
You may need a different test if TB outside the lungs is suspected, such as a biopsy.
Active TB is a notifiable disease. If you have it, your doctor will inform your local public health unit. They will work with you to find and trace close contacts.
ASK YOUR DOCTOR — Preparing for an appointment? Use the Question Builder for general tips on what to ask your GP or specialist.
How is tuberculosis treated?
For latent TB, your doctor may prescribe antibiotics to reduce the risk of TB reactivation. You will need to take them for at least 6 months. Not everyone with latent TB needs to be treated. Some people are checked over time.
For active TB, a combination of antibiotics may be prescribed. You will need to take them for at least 6 months. You’ll need to stay home from school or work until you’re no longer infectious. Your close contacts must be tested as well.
Treatment may be provided through a hospital clinic. Some people are treated by their GP. If you complete the full treatment, you have an excellent chance of being cured. Especially if it’s in early stages.
It’s important to take all your medicines as directed. Don’t stop taking your medicines early. If you don’t complete treatment, you may develop medicine-resistant TB. This means the infection does not respond to the usual antibiotics. This is harder to treat and you may need different medicines for up to 2 years.
What are the complications of tuberculosis?
Depending on the location of your infection, TB can damage your lungs or other organs. Complications may include:
- pneumothorax (air between your lungs and chest wall)
- lung damage
- respiratory distress or lung failure
If the bacteria spreads to your bloodstream, it can lead to a severe condition called miliary TB. This can affect multiple organs, including the:
There is also a risk of liver damage in people being treated for tuberculosis. To monitor this, your doctor will check your blood tests and general health during your treatment.
Can tuberculosis be prevented?
Active TB disease can be prevented with the bacille Calmette–Guérin (BCG) vaccine. It does not prevent you from becoming infected with TB. It helps prevent severe or life-threatening TB disease, especially in young children.
In Australia, most children do not need the BCG vaccine as TB is rare in Australia. The vaccine is not part of the National Immunisation Program schedule.
The vaccine is recommended for:
- Aboriginal and/or Torres Strait Islander children living in some parts of Australia
- children that travel to areas where TB is common
- babies with parents or carers who have TB
- young children exposed to leprosy at home
- some healthcare workers
The BCG vaccine is not always readily available in Australia. Ask your doctor or contact your state or territory immunisation health service to find out how to get the BCG vaccine. Other BCG vaccines may be available through special prescribing arrangements.
Everyone who may have been exposed to TB in the past should have a skin test before vaccination.
Tuberculosis vaccine
Vaccination is your best protection against the severe effects of TB. This table explains how the vaccine is given, who should get it and if it’s on the National Immunisation Program Schedule. Some diseases can be prevented with different vaccines. Talk to your doctor about which one is appropriate for you.
What age is it recommended? |
If needed, BCG can be given at any age. |
When to get vaccinated? |
BCG should be given after a risk assessment is conducted and only if the vaccine is available. |
How many doses are required? |
One. |
How is it administered? |
Injection into the skin, just below the surface (intradermal) |
Is it free? |
Find out more on the Department of Health website and the National Immunisation Program Schedule. Ask your doctor if you are eligible for additional free vaccines based on your situation or location. |
Common side effects |
The vaccine is safe and side effects are rare. A few weeks after the vaccination, a small, red sore forms and then becomes an ulcer before healing. There may be a scar. Lymph glands may get swollen and sore. |
Resources and support
- Department of Home Affairs website provides information on TB health requirements when moving to Australia.
- NSW Health provides information about BCG vaccination for your child.
- Lung Foundation Australia offers information and support services for Australians living with or impacted by lung disease.
You can also call the healthdirect helpline on 1800 022 222 (known as NURSE-ON-CALL in Victoria). A registered nurse is available 24 hours a day, 7 days a week.
Other languages
- NSW Health provides information about BCG vaccination for your child in languages other than English.
- NSW Health also offers tuberculosis fact sheets and patient information in languages other than English.
- The Northern Territory Government offers translated information on the Mantoux test in languages other than English.
Aboriginal and/or Torres Strait Islander peoples
- Australian Indigenous HealthInfoNet offers information and resources about TB for Aboriginal and/or Torres Strait Islander people.
- SA Health provides information on TB in Aboriginal and/or Torres Strait Islander people.
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Last reviewed: October 2024