Tuberculosis (TB) is no longer a common disease in New Zealand, however some parts of the world continue to have high rates of TB disease.
What is tuberculosis (TB)?
Tuberculosis (TB) is a disease caused by a type of bacteria known as Mycobacterium tuberculosis. TB is a serious disease but it can be successfully treated with antibiotics.
TB usually affects the lungs but the infection can spread from the lungs and affect any part of the body including bones, joints, glands, kidneys and the lining around the brain.
What are the symptoms?
Common symptoms of TB include:
- Unexplained weight loss.
- Excessive sweating at night.
- Unexplained tiredness.
- A cough that continues for more than 3 weeks – usually the cough produces thick phlegm and sometimes blood.
Other symptoms depend on which part of the body has been affected, for example, enlarged glands. Symptoms may only become apparent as the disease progresses.
What is latent TB?
When someone is first infected with TB the TB infection may be controlled but not destroyed by the body’s immune system. The person is not sick, has no symptoms of TB and is not infectious to others. This is known as latent TB infection (or LTBI). The person may never become sick with TB but does have a 5-10% chance of developing TB disease at some stage in their life. The risk of developing TB is higher in the first two years after first becoming infected and in people who have weaker immune systems (e.g. babies and young children; people with HIV infection, cancer; diabetes; kidney disease and people on medication that suppresses the immune system).
How are people infected?
TB can only be spread when a person has active TB in their lungs or throat and they expel bacteria into the air through coughing, sneezing, speaking or singing. This is called the infectious stage. Even when someone has infectious TB it does not spread easily. For someone to catch TB they usually need to be living or working closely with a person who is in the infectious stage of TB.
Usually once a person with TB has had two weeks or more of the correct antibiotics they are no longer considered infectious. If the person stops taking the antibiotics too early or misses doses they can become infectious again.
How is it treated?
Active TB disease is serious and needs to be diagnosed and treated early. TB can be cured with antibiotics but these may need to be taken for 6 to 12 months. It is important that the full course of treatment is taken and no doses missed otherwise the TB may come back or resistance to antibiotics may develop.
LTBI is often treated to reduce the chance of developing active TB disease in the future.
How do I protect myself and others?
See your doctor if you are concerned that you or someone you know may have symptoms of TB. The doctor can arrange TB tests or make a referral to a specialist. If someone is diagnosed with TB, family members and other people who have been in close contact with the sick person will be followed up by Public Health Services and will be offered advice, TB testing and antibiotic treatment if required. TB treatment is free to everyone.
Practice good hand hygiene and cover coughs and sneezes to reduce the spread of infection.
The vaccination for TB (known as the BCG vaccination) is available to children under the age of 5 years who are at risk of being exposed to TB. This includes children:
- at risk of catching TB from someone living in their house
- who are going to live in a country with a high rate of TB
- whose parents, household member or carer have in the last 6 months lived in a country with a high rate of TB
Information sources
Resources
For more information phone 0800 221 555 option 4 and ask for contact Brenda Dixon, Regional TB coordinator or by email brenda.dixon@bopdhb.govt.nz
Updated 28 Nov, 2023