A bacterial disease
Tuberculosis (TB), an airborne infection that attacks the lungs, is caused by Mycobacterium tuberculosis bacteria. About 8.8 million new cases occur worldwide each year, with some 15,000 infections annually in the United States. Once largely suppressed in developed countries, virulent, drug-resistant TB has recently made a comeback.
Avoid spending long periods of time with people who are coughing, especially in enclosed spaces. If you work among at-risk populations (hospital patients, prisoners, homeless persons), use a face mask. TB can almost always be cured with medicine, but must be treated properly, usually with multiple drugs.
Symptoms of TB include a persistent cough, pain in the chest and coughing up blood or phlegm. Weakness, fatigue, weight loss, chills, fever and night sweats can also occur. Most people infected with TB bacteria never develop symptoms. Some do not develop symptoms for months or years after infection.
Tuberculosis bacteria spread through the air. When an infected person coughs, talks or sneezes, another person breathes in airborne germs. The bacteria settle in the lungs, reproduce and then may move through the blood to other parts of the body. People with full-blown TB are contagious and most likely to spread the disease to others.