Latent TB Infection (LTBI)

Tuberculosis has two general states: latent TB infection and active TB disease. Only those who develop active TB can transmit the disease. If a person is diagnosed with latent TB infection it means that the person has inhaled TB bacteria and become infected with TB, but only has dormant (inactive) TB bacteria in their body.

Active TB Disease

• Usually, have signs and symptoms
• Usually feel sick
• May spread TB bacteria to others
• Usually, have a positive skin test reaction
• May have an abnormal chest x-ray, or positive sputum smear or culture
• Need treatment to treat active TB disease

TB is contagious, but not as contagious as other diseases such as the flu or chickenpox. To get infected, a person usually has to spend many hours over an extended period of time with the person who has infectious.