2017-04-05 06:02
The different stages of TB. Photo: sourced

The different stages of TB. Photo: sourced

Multimedia   ·   User Galleries   ·   News in Pictures Send us your pictures  ·  Send us your stories

TUBERCULOSIS, or TB, is a chronic infectious disease caused by a bacterium called Mycobacterium tuberculosis. It usually affects the lungs, but can attack other parts of the body.

It is mainly spread by breathing in air-borne bacteria from people with active infectious TB disease.

The bacteria can destroy parts of the lungs, making it difficult to breathe.

Bacteria can spread to, and damage other parts of the body, such as the digestive and urogenital tracts, bones, joints, nervous system, lymph nodes and skin.

This is called extrapulmonary TB, and is far less common. The disease is characterised by the development of granulomas or tubercles in infected tissues.

Tuberculosis symptoms may include:

· A cough that starts out dry but later produces blood or sputum (thick liquid from deep inside the lungs)

· Coughing for longer than a month

· Chest pain

· Breathing difficulty e.g. shortness of breath

· Weakness or fatigue

· Loss of weight and appetite

· Chills and fevers (the fever may be low and may be intermittent)

· Joint pain

· Wheezing

· Rales (additional sounds made to those of normal breathing)

· Excessive sweating, including sweating at night

· Hearing loss

· Diarrhoea

· A persistent lump or lesion

· Clubbing of fingers or toes – the nails become swollen and feel slightly “pulpy”.

Call a health professional if:

· You have been exposed to TB, or if symptoms develop

· Symptoms persist despite treatment

· New symptoms develop

While TB is a global problem and undeveloped countries usually have much higher incidences than developed countries. South Africa has one of the highest reported TB infection rates in the world. In some parts of the world, including South Africa, TB is the most important opportunistic infection of people with HIV.

Those at high risk for developing active TB include:

· People with HIV infection. Because HIV weakens the immune system, people with both TB and HIV infection are at high risk of developing TB disease. If you are HIV-positive, you are 30 times more likely to get active TB once infected than someone infected with TB who is HIV-negative. People with HIV should be TB tested and those with a positive skin test should get HIV tested. This way, someone with both infections can take medicine to reduce the chance of developing TB disease. Treatment is more difficult as the infecting bacteria are often resistant to therapy. However, among HIV-related diseases, TB is relatively preventable and curable.

· Patients receiving certain medical treatments (e.g. corticosteroid treatment, anti-cancer chemotherapy or transplant anti-rejection medication).

· People who have been in close contact with someone who has infectious TB.

· People who became infected with TB in the last two years.

· Babies and young children.

· People who inject drugs.

MOST important in TB prevention is for people with infectious TB to take their medicine as prescribed. If you are taking medication, you need regular check-ups and possibly additional chest X-rays or sputum tests to show whether the medicine is working, and whether you are still infectious.

If the tests show that you still have the bacteria in your sputum even after a few months of treatment, you may need to take some extra drugs, or change the drugs you are taking.

Detection of early cases and prompt treatment are crucial in controlling the spread of TB. The local health department may need to test people who have spent time with you for TB infection.

TB vVaccine (BCG)

The TB vaccine, BCG, is often given to babies and children in countries where TB is common, although its protective value is debatable. However, it is thought that BCG does offer increased protection against developing TB in parts of the body apart from the lungs (i.e. extra-pulmonary TB).

The vaccine’s efficacy varies throughout the world from 0 to 80%, but it is only effective in children, not adults.

In South Africa efficacy is about 60% against pulmonary TB.

In some countries, BCG is no longer given routinely, since the incidence of TB in those countries is very low. In other parts of the world, where there is a high prevalence of TB, BCG is given to children at birth as part of the routine vaccine schedule. It may also be given at three months, on entering school, and on leaving high school. BCG must not be given to a person with active TB. If you were vaccinated with BCG, you may have a positive reaction to a TB skin test, due to the BCG vaccine itself or to a real TB infection.

A positive reaction probably means that you have TB infection if:

· Your skin test reaction is large

· You were vaccinated many years before (the BCG reaction lessens over time)

· You have ever spent time with someone with infectious TB

· Someone in your family has had TB

· You are from a country where TB disease is common, such as South Africa

BCG vaccination should not be given to tuberculin-positive individuals, patients on corticosteroid or immunosuppressive therapy, and other causes of immune deficiency.

Adverse effects are rare. However, the vaccine may cause a local reaction in sensitive people, lasting about three days. Children visiting areas with a high risk of TB infection should be offered tuberculin skin esting, and BCG vaccination if the test is negative.

· Have spent time with someone with infectious TB

· Have HIV infection or another condition that puts you at high risk for TB disease

· Think you might have TB disease

· Are from a place where TB is common i.e. Africa, Latin America, the Caribbean and Asia (except Japan)

· Inject drugs

· Live where TB disease is common (homeless shelters, hostels, prisons, some nursing homes)

TB transmission

TB bacteria can stay air-borne for a long time (up to eight hours) in closed spaces such as classrooms, movie theatres and aeroplanes. They can also remain active in house dust for weeks. This means that risk of transmission is higher in confined spaces with minimal ventilation.

Someone with TB disease is most likely to spread it to people they spend time with daily, such as family members, friends and co-workers.

While it needs as few as 1–10 bacteria to establish infection, transmission usually only occurs after substantial exposure to someone with active TB.

Mycobacterium tuberculosis strains resistant to one or more anti-TB drugs have emerged. Multidrug-resistant TB (MDR TB) is when bacteria become resistant to at least the two first-line drugs, isoniazid and rifampin.

When people fail to complete treatment regimens or receive incorrect treatment, they may remain infectious.

Bacteria in their lungs may develop resistance to certain anti-TB drugs, which then can no longer kill the bacteria. People they infect will acquire the same drug-resistant strain. When drug treatment stops, the resistant bacteria will being to multiply and cause active disease again, for which treatment options are limited.

The end result is drug-resistant TB, a form of TB that doesn’t respond to treatment. Drug-resistant Mycobacterium tuberculosis strains may emerge due to inconsistent or partial treatment, when patients do not take all their medicines regularly for the required period because they start to feel better, health workers prescribe the wrong drugs or the wrong combination of drugs, or the drug supply is unreliable.


XDR-TB stands for Extensively Drug Resistant TB (also referred to as Extreme Drug Resistance). This is MDR-TB that has also become resistant to three or more of the six classes of second-line drugs.

This description of XDR-TB was first used earlier in 2006, after a survey by the World Health Organisation and the US Centres for Disease Control and Prevention.

XDR-TB is a serious global concern as there are limited treatment options available for people infected with these strains. An outbreak of XDR-TB in KwaZulu-Natal in 2006 killed 52 out of 53 people infected. XDR-TB is of particular concern in areas where the HIV prevalence is high, and is especially difficult to treat in HIV-positive people. - Health24

Join the conversation!

24.com encourages commentary submitted via MyNews24. Contributions of 200 words or more will be considered for publication.

We reserve editorial discretion to decide what will be published.
Read our comments policy for guidelines on contributions.

Inside News24

Traffic Alerts
There are new stories on the homepage. Click here to see them.


Create Profile

Creating your profile will enable you to submit photos and stories to get published on News24.

Please provide a username for your profile page:

This username must be unique, cannot be edited and will be used in the URL to your profile page across the entire 24.com network.


Location Settings

News24 allows you to edit the display of certain components based on a location. If you wish to personalise the page based on your preferences, please select a location for each component and click "Submit" in order for the changes to take affect.

Facebook Sign-In

Hi News addict,

Join the News24 Community to be involved in breaking the news.

Log in with Facebook to comment and personalise news, weather and listings.