The germs are put into the air when a person with TB of the lung coughs, sneezes, laughs or sings. To get TB, you usually need to have very close, daily contact with someone who has the disease.
Most people get it from a family member, friend, partner, or co-worker.
You're not likely to get TB from someone coughing on the subway or at a restaurant. It is not spread by dishes, drinking glasses, sheets or mattresses. A positive result for tuberculosis means that sometime in your life, you breathed TB germs into your lungs. The germs make some people sick soon after they enter the body, causing TB disease. In most cases, the body's immune system controls the disease by building a wall around the germs the way a scab forms over a cut.