Exposure and Transmission

• According to the World Health Organization, the tuberculosis bacilli currently infects about a third of the world's population and infects someone new every second. Tuberculosis spreads through the air when an infected person laughs, coughs, sings, spits, sneezes or talks, propelling the bacterium, which is then inhaled by someone else. Only people with an active form of the disease are contagious. If you have shared breathing space with an infected person without the use of a proper mask, you have been exposed to tuberculosis and should watch carefully for signs of possible infection.
  
  

Incubation

• According to the Vanderbilt Occupational Health Clinic, the incubation period of tuberculosis is from two to 10 weeks. The incubation period indicates how long it usually takes from infection until a TB skin test shows positive. Someone that has tested positive for TB is at the greatest risk for developing an active form of the disease within the first two years. Only five to 10 percent of those infected ever develop an active form of the disease.
  
  

Testing

• If you have symptoms of tuberculosis such as coughing, night sweats, tiredness, fever, weight loss, blood in your sputum, have been exposed to someone with active tuberculosis, are a health care worker, have lived or traveled in a country with a high incidence of tuberculosis or for some job applications, you may be asked to take a tuberculosis test. For the tuberculosis test, a fluid is placed under the skin using a small needle. After a few days, you must return to the doctor to determine if the test is positive or negative. If the test is positive, you will likely receive a chest x-ray and be screened for signs of active disease.
  
  

Treatment

• Treatment for tuberculosis consists of taking antituberculosis medications for a minimum of six months. There are currently 10 drugs approved for treating tuberculosis in the United States and others that are used to supplement those drugs. The core treatment typically includes the following medications: isoniazid (INH), rifampin (RIF), ethambutol (EMB) and pyrazinamide (PZA). Your doctor will continue to observe and test until the active disease is eradicated. However, you will always test positive to the tuberculosis skin test.
  
  

Considerations

• While treatment and outcomes for tuberculosis remain positive, especially in the developed world, the concern continues to be the development of drug-resistant strains. Currently, there are TB strains resistant to all of the major treatment drugs. Drug-resistant tuberculosis requires a much longer treatment period at greater expense and greater health risk. While tuberculosis remains a worldwide problem, the World Health Organization estimates that its incidence peaked in 2004 and is now decreasing.