What is Tuberculosis?

Tuberculosis (TB) is a serious disease caused by the germ Mycobacterium tuberculosis. Mycobacterium bovis is part of the tuberculosis family, primarily a disease of cattle but may affect other animals as well as humans. TB can hurt a person’s lungs or other parts of the body. However, TB can be prevented with treatment and it can be cured.
 
In spite of the availability of chemotherapy for TB, there are 14 million Tuberculosis cases in India and a staggering 5,00,000 deaths every year due to this disease. Most TB cases occur in the 15-59 year age group (economically the most productive years).
 
TB kills more adults each year than any other infectious disease – more than malaria, diarrhea, AIDS and other tropical diseases put together. Awareness about the symptoms of the disease and removal of the stigma about the disease are crucial factors in TB control.

How are TB germs spread?

TB is spread when a person who has active, untreated TB germs in their lungs or throat coughs, sneezes, laughs, or speaks, spreading their germs into the air. A person who breathes in TB germs usually has had very close, day-to-day contact with someone who has active TB disease. That’s why a person usually gets TB germs from someone he/she spends a lot of time with, like a family member, friend, or close co-worker who has the disease.
 
A person is not likely to get TB from someone coughing in the subway or at a restaurant. TB is not spread by sitting on a toilet seat or by sharing dishes, utensils, sheets, clothing or other inanimate objects.

What happens when someone breathes in TB germs?

When you first breathe in TB germs into your lungs, your body protects you by building a wall around the germs the way a scab forms over a cut. This makes the germs go to “sleep” and stops them from hurting your body. Sleeping TB germs are called “latent TB”. A person with latent TB are said to have latent TB infection (LTBI). Latent TB germs can stay asleep for a long time, sometimes for life. However, sometimes TB germs “wake up” when body defenses are weakened. When this happens, you have active TB disease.

What is TB active disease?

Some people develop TB disease soon after becoming infected when TB bacteria begin to multiply rapidly, before their immune system can fight back. Other people may get sick later, when their immune system becomes weak for some reason.
 
Babies and young children often have weak immune systems. People infected with HIV have very weak immune systems. Other people who have weak immune systems, are those who have the following conditions:

  • diabetes mellitus
  • cancer of the head or neck
  • hematological malignancies
  • severe kidney disease
  • low body weight
  • certain medical treatments (such as corticosteroid treatment or organ transplants)