title: What is an epidemic? AIDS in historical perspective.
mesh_terms: D000163:Acquired Immunodeficiency Syndrome / Q000453:epidemiology* / Q000635:transmission; D004196:Disease Outbreaks / Q000266:history*; D005060:Europe; D049671:History, 18th Century; D049672:History, 19th Century; D049673:History, 20th Century; D006801:Humans; D011634:Public Health / Q000266:history*; D012945:Social Values; D014481:United States