How Does TB Cause?

Tuberculosis (TB) is a bacterial infection caused by the bacterium Mycobacterium tuberculosis. It primarily affects the lungs but can also affect other parts of the body, such as the lymph nodes, bones, and nervous system. TB is primarily spread through the air when an infected person coughs, sneezes, talks, or sings, releasing tiny infectious droplets into the air that can be inhaled by others.

Here’s how TB infection typically occurs:

  1. Inhalation of Bacteria: When a person with active TB in their lungs coughs or sneezes, they release infectious droplets into the air. If another person inhales these droplets, they may become exposed to the TB bacteria.
  2. Lung Infection: The inhaled TB bacteria reach the lungs and can establish an infection. The immune system responds by sending white blood cells to the site of infection to try to contain the bacteria.
  3. Granuloma Formation: In most cases, the immune response forms small, dense nodules called granulomas around the bacteria. Granulomas help to contain the infection and prevent the bacteria from spreading further in the body.
  4. Latent TB vs. Active TB: In some cases, the immune response successfully contains the bacteria, and the infection remains in a dormant state. This is known as latent TB infection, and the person may not show any symptoms or be contagious. However, if the immune system weakens, the bacteria can become active and cause symptomatic TB disease.
  5. Active TB Disease: If the immune system is unable to control the bacteria, they can multiply and cause active TB disease. This can lead to symptoms such as persistent cough, fever, night sweats, weight loss, and fatigue. Active TB is contagious and can be spread to others through airborne transmission.

It’s important to note that not everyone who is exposed to the TB bacteria becomes sick. Many people with latent TB infection never develop active TB disease. Certain factors, such as a weakened immune system (e.g., due to HIV infection, malnutrition, or certain medications), increase the risk of latent TB infection progressing to active disease.

TB is a serious and potentially life-threatening condition, but it can be treated and cured with appropriate medications. If you suspect you have been exposed to TB or are experiencing symptoms, it’s important to seek medical attention for diagnosis and treatment.