How is it passed?
It is an airborne disease, passed from person to person via inhalation. When people talk, laugh, cough, sneeze, etc., tiny droplets are released into the air that may be inhaled by another person. When a person infected with tuberculosis does any of these things, their tiny drops contain the bacteria (remember, the bacteria are resistant to oral fluids- they can survive in such environments). Immune deficiency disorders can severly increase your probability of catching and dying from diseases like this- yet another point in favor of safe sex! Anyway, they reach the alveoli, which are tiny sacs in your lungs, and from there spead throughout your body via your bloodstream. They multiply quickly in organs, like lungs and kidneys, that have high oxygen pressures.