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This fact sheet answers frequently asked questions about Tuberculosis.

“TB” is a short name for tuberculosis. TB spreads by tiny germs that can float in the air.

Learn more from the CDC

The basics

What is "TB?"

When a person with TB coughs, sneezes or shouts they can spray these germs into the air. If another person breathes in these germs, they can get TB. Most people think that TB only affects your lungs. 70% of those infected with tuberculosis have the germs in their lungs. However, TB can infect other places in the body such as the bone, brain, or heart. 

Some people may have the TB germ in their body, without feeling sick. People who don't feel sick have latent or "sleeping" TB, and people who feel sick have active TB.

How do I know if I'm infected? 

A simple test on your arm can tell if you have the TB germ in your body. A positive TB skin test usually means that you have the TB germ. You may need additional tests such as a chest x-ray or sputum test.

What is the difference between sleeping TB and active TB? 

Latent Tuberculosis Infection (LTBI) is also called sleeping TB because the germs stay asleep as long as your body can fight them. You may have a positive test for TB but a normal chest x-ray if you have sleeping TB. You cannot spread it to others, but if you take TB medications there is less chance of waking up the germs. 


Active TB germs are active in the body and can spread to the lungs or other parts of the body and make you very sick. With active TB, you have a positive skin test, and may have a positive chest x-ray test and you feel sick. 


Symptoms that can occur in the body when TB becomes active include:

Body Location symptoms
Lungs Cough, increased sputum (phlegm), coughing blood
Glands of the neck Lumps in the neck
Bones Pain in the bones or back
Head Headache, pain when moving head, stiff neck, fever


 What if I have TB? 

You can take medication to cure TB. Even if you feel better after you begin taking medication, do not stop taking the pills until directed by your doctor or nurse. If you stop taking the medication too soon, the TB germ can come back and be very hard to fight off.​

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