Tuberculosis (TB) is an infectious disease caused by bacteria. While not common in the United States, TB affects millions of people around the world and can be life-threatening without treatment.

TB infection most commonly develops in the lungs, called pulmonary tuberculosis. It can affect many other places in the body, though, such as the: 

• Bones
• Brain (TB meningitis)
• Kidneys
• Lymph nodes
• Skin
• Spine (Pott’s disease)

You can have TB as an inactive (latent) or active infection: 

• Inactive TB: The bacteria exist in your body, but your immune system keeps them from growing and spreading. With inactive TB, you are not sick or contagious. 
• Active TB: Your immune system cannot stop the bacteria from growing and spreading. The bacteria infect your body, causing symptoms and harming your health. With active TB, you are contagious.

Inactive TB does not always progress to active TB. But it can happen over time, so getting treatment as soon as possible is important. Whether or not you become sick depends on many factors, such as the amount of exposure you have to TB and the strength of your immune system. 

A bacteria called Mycobacterium tuberculosis most commonly causes TB infection. In some cases, other types of mycobacteria can cause TB.

TB bacteria spread through the air. A person with active TB can spread the disease by breathing, coughing or talking around others.

Usually, you catch TB if you spend a long time around an infected person, such as living or working with them. TB also spreads more easily in environments with poor air circulation. 

Risk factors are things that increase your chance of getting inactive or active TB. Talk with your provider about your risk factors, including:

We offer prompt and accurate TB testing at UC Davis Health. Our compassionate team is here for you if you think you may have been exposed or face a high risk for developing active TB. We also offer routine TB testing for employment, school or travel requirements.

Be sure to tell your provider if you have received a TB vaccine. The vaccine can interfere with the accuracy of some TB tests. Our specialists will recommend the right testing method for you.

To check if TB bacteria exist in your body, we offer a:

• TB blood test, which involves analyzing a sample of your blood
• TB skin test (PPD test), which involves injecting a solution called purified protein derivative under your skin and checking for an inflammatory (swelling) reaction within 48 to 72 hours

If you have a positive TB test, we do more in-depth tests to learn whether the infection is inactive or active. We may do: 

• Bronchoscopy, which allows us to see your airways and lungs using a thin, flexible tube with a camera
• Biopsy, where we take a small tissue sample of the infected area
• Imaging, such as a chest X-ray or CT scan
• Urine or sputum test, which analyzes the bacteria in your urine or the mucus coughed up from your lungs

Our infectious disease specialists support you throughout treatment for TB. We can cure most inactive and active TB infections with antibiotics.

It’s important to take your TB medication as instructed and complete your full treatment regimen. Otherwise, TB bacteria in your body can become antibiotic resistant. Antibiotic-resistant TB is difficult to treat and therefore more dangerous to risk spreading to others.

We develop a TB treatment plan tailored to your overall health and the type of infection you have. Our specialists consider everything that may make treatment more complex, such as pregnancy or HIV.

You can take steps to prevent getting and spreading TB. Talk to your provider if you know that you face a high risk for exposure or for developing active TB. Ask about: