Tucerculosis

Tuberculosis, MTB, or TB (short for tubercle bacillus) is a common, and in many cases lethal, infectious disease caused by various strains of mycobacteria, usually Mycobacterium tuberculosis.[1]Tuberculosis typically attacks the lungs, but can also affect other parts of the body. It is spread through the air when people who have an active TB infection cough, sneeze, or otherwise transmit theirsaliva through the air.[2] Most infections are asymptomatic and latent, but about one in ten latent infections eventually progresses to active disease which, if left untreated, kills more than 50% ofthose so infected.
The classic symptoms of active TB infection are a chronic cough with blood-tinged sputum, fever, night sweats, and weight loss (the latter giving rise to the formerly prevalent term"consumption"). Infection of other organs causes a wide range of symptoms. Diagnosis of active TB relies on radiology (commonly chest X-rays), as well as microscopic examination and microbiologicalculture of body fluids. Diagnosis of latent TB relies on the tuberculin skin test (TST) and/or blood tests. Treatment is difficult and requires administration of multiple antibiotics over a long periodof time. Social contacts are also screened and treated if necessary. Antibiotic resistance is a growing problem in multiple drug-resistant tuberculosis (MDR-TB) infections. Prevention relies onscreening programs and vaccination with the bacillus Calmette–Guérin vaccine.
One third of the world's population is thought to have been infected with M. tuberculosis,[3] with new infections occurring ata rate of about one per second.[3] In 2007, there were an estimated 13.7 million chronic active cases globally,[4] while in 2010, there were an estimated 8.8 million new cases and 1.5 millionassociated deaths, mostly occurring in developing countries.[5] The absolute number of tuberculosis cases has been decreasing since 2006, and new cases have decreased since 2002.[5] The distribution of...