About Mycobacterium tuberculosis
Tuberculosis (TB) is one of the most prevalent infectious diseases worldwide and accounts for a large portion of all preventable deaths. Latent TB infection is also extremely common, affecting as many as one-third of humans alive today. Fortunately, only about 10% of TB infection leads to active TB disease. TB is curable with proper treatment, but treatment programs are labor intensive and increasingly threatened by drug resistance. Furthermore, the long treatment regimen poses compliance problems, and lack of access to TB care is common. As a consequence of these combined factors, TB continues to claim 2 million lives per year. An effective vaccine reliably preventing TB disease in adults would significantly reduce the number of deaths due to TB; however, no such vaccine is available. A live attenuated strain of Mycobacterium bovis, bacille Calmette–Guérin (BCG), is used with variable efficacy to vaccinate children against TB in many countries throughout the world.