A third of the world's population are thought to be infected with M. tuberculosis, and new infections occur at a rate of about one per second. More people in the developed world are developing tuberculosis because their immune systems are compromised either by HIV/Aids, poor nutrition and poverty as well as age and other immune compromising conditions. In 2007 there were an estimated 13.7 million chronic active cases, 9.3 million new cases, and 1.8 million deaths, mostly in developing countries..
