One-third of the world’s population is infected with Mycobacterium tuberculosis, the pathogen responsible for causing tuberculosis (TB). In 2011, there were an estimated 8.7 million incident cases of TB globally. Despite the fact that diagnostic and treatment services for TB are integrated with primary health care in most countries, the number of deaths due to TB remains high—1.4 million in 2011.
Of the 15 countries with the highest incidence of TB, 14 are in Africa. This is largely due to HIV—40% to 50% of people with HIV will develop TB disease in their lifetime. In fact, nearly one-quarter of the estimated 1.8 million HIV-related deaths in 2009 were due to TB.