Tuberculosis epidemiology is the field of science that is concerned with the study of health and disease within populations and the various factors that lead to these conditions, with a goal of preventing the spread of disease. One-third of the world's population has been infected with M. tuberculosis. 13.7 million Chronic active cases, were reported by 2007 and 8.8 million new cases were estimated in 2010 and 1.45 million deaths, are often noted in developing countries. Out of these, 0.35 million deaths occur in those co-infected with HIV. In 2012, around 450,000 people developed MDR-TB. TB incidence varies with age. In Africa, TB chiefly affects adolescents and young adults. However, in United States, TB has gone from high to low incidence, where TB is mainly a disease of older people, or of the immunosuppressed.
Since 1985, Lung cancer has been the most common cancer in the globe. Worldwide, lung cancer, new cancer diagnosis (134 thousand people and 12.4% of new cancer patients) and cancer fatalities (1,180,000 deaths, 17.6% total cancer deaths). COPD is the fourth leading cause of death in the United States and is related to age. Lung cancer increases with age, especially after age 60. The average age of patients diagnosed with lung cancer is 70 years.