What is the Difference?
Tuberculosis Infection or Latent TB (LTBI) means that the person has been exposed to the bacteria that cause tuberculosis. They are not sick because the bacteria are inactive and they cannot spread the bacteria to others. A person with tuberculosis infection usually has a positive skin test, a normal chest x-ray and does not feel sick. An average of one in ten infected persons develop tuberculosis disease at sometime in their lifetime unless given preventive therapy. However, persons who are infected with the tuberculosis bacteria and have HIV infection may not show a reaction to the tuberculosis skin test, and are at considerably greater risk of developing tuberculosis disease. Persons with tuberculosis infection may be given Isoniazid (INH) for six months to prevent tuberculosis disease from developing.
Tuberculosis disease means that the person is sick from bacteria that are actively reproducing in their body. Persons with pulmonary tuberculosis usually have a positive skin test, an abnormal chest x-ray and one or more of the symptoms of tuberculosis such as persistent cough, chest pain, feeling weak, weight loss, fever and/or night sweats. These people are often capable of giving the infection to others. Persons with tuberculosis disease should be treated with four anti-tuberculosis medications to treat the disease.