Because of both public health and clinical advances, there have been tremendous reductions in the rates of infectious diseases in all eight countries. Similar reductions are seen in other OECD countries over different time periods. Note the number of deaths from infectious diseases include AIDS. As the prevalence of infectious diseases declined; more attention turned to acute illnesses. In most OECD countries, all five components of the health care system became focused on preventing and treating acute illnesses. Acute illness became the primary concern of the latter half of the 20th century.