What is tuberculosis?
Tuberculosis is an infectious disease that can cause infection in your lungs or other tissues. It commonly affects your lungs, but it can also affect other organs like your spine, brain or kidneys. The word “tuberculosis” comes from a Latin word for “nodule” or something that sticks out.
Tuberculosis is also known as TB. Not everyone who becomes infected with TB gets sick, but if you do get sick you need to be treated.
If you’re infected with the bacterium, but don’t have symptoms, you have inactive tuberculosis or latent tuberculosis infection (also called latent TB). It may seem like TB has gone away, but it’s dormant (sleeping) inside your body.
If you’re infected, develop symptoms and are contagious, you have active tuberculosis or tuberculosis disease (TB disease).
The three stages of TB are:
- Primary infection.
- Latent TB infection.
- Active TB disease.
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How common is tuberculosis?
About 10 million people became ill with TB throughout the world, and about 1.5 million people died from the disease in 2020. TB was once the leading cause of death in the U.S. but the number of cases fell rapidly in the 1940s and 1950s after researchers found treatments.
Statistics show that there were 7,860 tuberculosis cases reported in the U.S. in 2021. The national incidence rate is 2.4 cases per 100,000 people.
Are there different kinds of tuberculosis?
In addition to active or inactive, you might hear about different kinds of TB, including the most common, pulmonary (lung) tuberculosis. But the bacterium can also affect other parts of your body besides the lungs, causing extrapulmonary tuberculosis (or TB outside of the lung). You might also hear about systemic miliary tuberculosis, which can spread throughout your body and cause:
- Meningitis, an inflammation of your brain.
- Sterile pyuria, or high levels of white blood cells in your urine.
- Pott’s disease, also called spinal tuberculosis or tuberculosis spondylitis.
- Addison’s disease, an adrenal gland condition.
- Hepatitis, a liver infection.
- Lymphadenitis in your neck, also called scrofula or TB lymphadenitis.
