Understanding Tuberculosis (TB): Causes, Symptoms & Transmission

Tuberculosis (TB) is caused by a bacterium called *Mycobacterium tuberculosis*. The bacteria usually attack the lungs, but can also spread to other parts of the body, such as the brain, kidneys, or spine.

TB is spread through the air when an infected person coughs, sneezes, or speaks. People who are in close contact with someone who has TB are at the greatest risk of infection.

TB can also be spread through contact with infected animals or animal products. This is most common in countries where people drink unpasteurized milk or eat raw meat.

TB is not always contagious. People who have latent TB infection do not have any symptoms and cannot spread the disease to others. However, latent TB infection can turn into active TB disease if the person's immune system is weakened.

Risk factors for developing active TB disease include:

* Being infected with HIV

* Diabetes

* Cancer

* Kidney disease

* Substance abuse

* Smoking

* Being pregnant

* Being underweight

* Living in poverty

* Being homeless

TB can be treated with antibiotics. However, it is important to take the medication exactly as prescribed and for the entire course of treatment. If TB is not treated properly, it can become drug-resistant and more difficult to treat.