Tuberculosis (TB) is caused by a bacterium known as Mycobacterium tuberculosis. It spreads when someone with active tuberculosis in their lungs coughs or sneezes and someone else inhales the ejected droplets, which contain tuberculosis germs. People are not born with immunity to TB because they have never been exposed to it. If you have been vaccinated against TB but still get infected, you might be able to fight off the disease without getting sick. The best way to avoid getting TB is to not go around spreading the infection anyway possible. This includes not sharing needles used for drug addiction or blood transfusions with people who have not been treated for the infection. If you do get infected, there are drugs that can kill the bacteria and keep you healthy. The problem is that these drugs take months to become effective and many patients stop taking them, leaving them vulnerable to relapse if they ever were to become infected again. The best defense against TB is early detection and proper treatment. If someone suspects they may be infected, they should contact their doctor right away so an appointment can be made to receive testing. If detected early, TB is very treatable. There are several different types of medications that can kill the bacteria and help clear up the infection.