As of 2016, it was estimated that TB was responsible for around 1.3 million deaths a year worldwide, with most TB cases and deaths occurring in developing countries, particularly in Africa and Southeast Asia. India has the highest number of deaths from tuberculosis worldwide, with around 423,000 deaths from the disease reported in 2016. However, the three countries with the highest death rates from TB in 2016 were all found in Africa. Cases of TB in developed countries have decreased steadily over the past few decades, with cases in the United States dropping to a rate of 3 per 100,000 population in 2015.
People with certain diseases and lifestyles are more prone to active TB, as their immune systems are not as capable of fending off the disease. Those at greater risk include people with HIV or AIDS, kidney disease, and diabetes, as well as those who smoke. In 2015, an estimated 55 percent of all tuberculosis patients worldwide were given HIV tests, a substantial increase from 8.5 percent in 2005. Tuberculosis caused around 277,000 deaths among HIV-positive adults in Africa in 2016, with the highest number of HIV-positive tuberculosis cases found in South Africa.