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Tuberculosis (TB)


Tuberculosis (TB) is a bacterial disease of the lungs caused by the bacterium Mycobacterium tuberculosis. Though TB primarily infects the lungs, it can even harm other parts of the body. TB is communicated by the infected person when someone inhales the germs that are expelled when he/she coughs or sneezes. TB cannot be caused by a mere touch or shaking hands. A weak immune system is more prone to catching the infection, which can be fatal if not treated properly. In olden days, the disease was incurable and led to innumerable deaths, but now it can be cured successfully with antibiotics.

Signs and symptoms of tuberculosis
A strong immune system can prevent the TB bacteria from reproducing quickly, and the disease may remain dormant for months or even years, but if the immune system is weak the bacteria can easily take over and also infect other parts of the body. Some of the danger signs to look out for are:

  • Chronic cough that lasts a couple of weeks or more
  • Sudden weight loss
  • Blood or mucus in the cough
  • Pain in the chest
  • General fatigue or weakness
  • Fever and chills
  • Night sweats

The doctor will normally take a chest x-ray or will analyse a sample of the sputum, or both, and the presence of TB can be easily detected through these tests. Some skin tests can also determine the presence of TB germs, like the Tine test and the PPD (purified protein derivative) test. A small amount of purified extract from dead TB bacteria is injected under the skin. If a person is not infected with TB no reaction will occur at the site of the injection, but if the person is infected than the area will become swollen or red.

Prevention and treatment
A vaccine called BCG (Bacille Calmette Guerin) is administered to children or infants to prevent them from catching the disease later in life, but it is not always a fool-proof preventive method, as even after a person has been vaccinated during childhood the disease is known to have occurred in adulthood.

If a person is showing no symptoms, a normal chest x-ray, but a positive skin test conducted for TB, he may be carrying the disease in the dormant stages, and that is why, to prevent it from becoming full-blown, treatment with antibiotics is usually recommended by doctors. A 6-12 month course of antibiotics (usually isoniazid) is usually enough to prevent the disease from turning active later in life. However, antibiotics are not recommended during pregnancy, or if the person is suffering from a liver disease, or is an alcoholic, because antibiotics can have certain side-effects that can make the individual feel irritable or fatigued.

In the active stage, TB is treated with a combination of four antibiotics for the first two months to eliminate any strain of the bacteria, and then, depending on the patient’s sensitivity to the antibiotics, the dosage is reduced to two antibiotics.
Streptomycin injections also may have to be used when the patient does not respond to oral medication or if the disease is full-blown. The success of the treatment, because it is a long-term treatment, depends much on the cooperation from the patient. Also, there is a possibility that the patient may develop an immunity to antibiotics. Surgery in the lungs is the last resort, but with effective antibiotics easily available, it is rarely required.

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