Tuberculosis (TB) is an infectious disease caused by a type of bacteria called Mycobacterium tuberculosis. TB most commonly affects the lungs, when it is called pulmonary tuberculosis, but also can involve any other organ of the body in which case it is called extra-pulmonary tuberculosis. These FAQs are about pulmonary TB.
Frequently Asked Questions about Tuberculosis. (2013). [ebook] New Delhi-110002, India: Regional Office for South-East Asia, World Health Organization. Available at: http://www.searo.who.int/about/administration_structure/cds/ en/index.html [Accessed 1 Jan. 2018].
TB is spread primarily from person to person through infected air during close contact. The bacteria get into the air when someone infected with TB of the lung coughs, sneezes, shouts, or spits. A person can become infected when they inhale minute particles of the infected sputum from the air. It is not possible to get TB by just touching the clothes or shaking the hand of someone who is infected.
TB germs spread more easily in crowded conditions as the bacteria sometimes stay alive in the air for a few hours, especially in small closed places with no fresh air. Fresh air scatters the germs and sunlight acts as a bactericide, killing the TB organisms. Exposure to moderately hot temperatures for extended periods of time is sufficient to kill these bacteria. Extra-pulmonary TB does not spread from person to person.
If you are infectious while you are taking rest at home, you can do the following things to protect others near you.
Take your medicines as directed. This is very important!
Always cover your mouth with a tissue when you cough, sneeze, or laugh. Put the tissue in a closed bag and throw it away safely.
Isolate yourself from others and avoid close contact with anyone. Sleep in a bedroom away from other family members for the first few weeks.
Air out your room often to the outside of the building (if it is not too cold outside). TB spreads in small closed spaces where air doesn’t move. Put a fan in your window to blow out air that may be filled with TB bacteria. If you open other windows in the room, the fan also will pull in fresh air. This will reduce the chances that TB bacteria will stay in the room and infect someone who breathes the air.
After you take the medicines for about 2 or 3 weeks, you might no longer be able to spread TB bacteria to others. If your doctor or nurse agrees, you will be able to go back to your daily routine, including returning to work or school. But remember, you will only get well if you take your medicines exactly as directed by your doctor or nurse.
Think about people who may have spent time with you, such as family members, close friends, and co-workers. The local health department may need to test them for TB infection. TB is especially dangerous for children and HIV-infected persons. If these people are infected with TB bacteria, they need medicines right away to keep them from developing active TB disease.
When a person breathes in the TB bacteria, in most cases, the body is able to fight them to stop them from growing. The bacteria become inactive, but do not die. They lie latent, and can become active later. This state is called TB infection. People who are infected with TB do not feel sick, do not have any symptoms, and cannot spread the disease. But they could develop TB disease at some time in the future.
Frequently Asked Questions about Tuberculosis. (2013). [ebook] New Delhi-110002, India: Regional Office for South-East Asia, World Health Organization. Available at: http://www.searo.who.int/about/administration_structure/cds/ en/index.html [Accessed 1 Jan. 2018].
Not all people with TB infection get active TB disease. Only when people infected with the TB bacteria start showing signs and symptoms associated with TB are they considered to have active TB disease. Some people develop TB disease soon after becoming infected, before their immune system can fight back. Other people may get sick later, when their immune system becomes weak for some reason.
People with weak immune systems are more vulnerable to TB. This includes babies and young children, people infected with HIV and those who have the following conditions:
diabetes mellitus
silicosis
cancer of the head or neck
eukaemia or Hodgkin’s disease
severe kidney disease
low body weight
certain medical treatments (such as corticosteroid treatment or organ transplants)
Frequently Asked Questions about Tuberculosis. (2013). [ebook] New Delhi-110002, India: Regional Office for South-East Asia, World Health Organization. Available at: http://www.searo.who.int/about/administration_structure/cds/ en/index.html [Accessed 1 Jan. 2018].
Only persons with active TB disease (i.e. those who also show signs and symptoms of the disease) can spread TB to others. People with latent TB infection (i.e. people who have the TB bacteria but do not show any symptoms) cannot spread TB bacteria to others. A person exposed to someone with active TB disease, may become infected with the TB bacteria, but would not be able to spread the infection unless he or she starts showing symptoms of the disease. People who have latent TB infection can, however, be treated to prevent them from developing active TB.
BCG is a vaccine for TB, routinely given to infants and small children. BCG vaccine protects against the severe, life-threatening forms of extra-pulmonary TB such as TB meningitis and miliary TB in childhood. However, it is unreliable protection against pulmonary TB, the main form of tuberculosis.
The best way to get tested for pulmonary TB is by getting the sputum examined. The TB-causing germs can be seen through a microscope. At least two samples of sputum should be examined for accurate diagnosis.
The examination is available at public health facilities, often within easy reach of the patients. In the facility, the health-care provider may ask the person suspected of TB to collect two sputum samples and explain how to produce and collect them. It is important to carefully follow what the health-care provider advises to make sure the diagnosis is correct.
The health-care provider may also advise a chest X-ray if the patient is suspected of having symptoms of TB and if TB germs are not seen through the sputum examination.
Yes. TB can be cured if the full course of the prescribed drugs is taken regularly, and without interruption. The WHO-approved standardized and effective cure for TB, called DOTS (directly-observed treatment, short-course) is available in all countries of the South-East Asia Region. It takes at least 6–8 months of medication to completely treat the disease. It is very important that the patient takes all the prescribed drugs for the recommended duration.
It is dangerous, both for the patient, family members and the community, if he/she stops taking medication before the prescribed course is completed and without medical advice. The TB germs that are still alive become even stronger, or ”resistant” to the drugs. Stronger drugs are then needed to kill these “super” TB germs if the treatment is not completed the first time.
