ng TB. In people with HIV, the immune system may eventually lose control of the bacteria, causing the infection to spread and cause active disease. This process can take many months or years. In other words, Mycobacterium tuberculosis can remain alive in someone's body for many years, but may only become active once the immune system becomes damaged.
             About 15 years ago TB was on its way to becoming extinct. But with the HIV epidemic actively flourishing, TB rates started increasing again between 1985 and 1992. Since 1992, the total number of TB cases has once again decreased. However, in certain groups of people in the U.S., such those immigrating to the United States from countries where TB rates are very high, the TB rate is increasing. In 2000, there were 17,531 cases of TB. Although the number of TB cases continues to decrease, it remains one of the most common causes of sickness and death in U.S. residents infected with HIV. In fact, TB is the number-one cause of death of HIV infected people across the globe.
             Because of this a person should be checked for TB if they have some of its
             symptoms which include cough, night sweats, chills, weight loss, fever and fatigue. To
             test for the Mycobacterium tuberculosis infection, a skin test called purified protein derivative (PPD) can be performed in a clinic or doctor's office. It contains pieces of the bacteria and is injected directly under the skin. If someone has been exposed to the bacteria in the past, the immune system will immediately recognize the PPD, resulting in a firm, relatively large bump at the site of the injection. If this reaction occurs, a person is said to have a positive PPD. A positive PPD generally calls for additional testing. An X-ray of the chest is performed to look for signs of active disease. Blood tests, along with sputum (phlegm) samples, may also be sent to a lab for analysis. If the bacteria is found in these samples, it may be tested f...