Tuberculosis is a disease that can be spread from person to person through the air.
TB usually affects the lungs. The germs are put into the air when a person with TB of the lung coughs. About 8 million new cases occur each year in the world, over 18,000 cases were reported for 1998 in the United States. There are also an estimated 10 to 15 million people in the US who are infected with the TB germ, with potential to develop TB disease in the future. The city of Atlanta has high rates of TB, especially among HIV patients, but the number of new cases is beginning to decrease due to public health control efforts.