TB is spread from person to person through the air. When people with TB disease of the lungs or throat cough or sneeze, they can put TB germs into the air. Then other people who breathe in the air containing these germs can become infected. People with TB disease are most likely to spread it to people with whom they spend time with every day, such as family members or coworkers. (Remember, though, a person must have active TB disease to spread it; persons who are infected but do not have the disease cannot spread TB to others.) If a person thinks he or she has been in close contact with someone with TB disease, it is important to go to a clinic or health department for a TB skin test.