AIDS vs acquired immune deficiency syndrome

AIDS

noun
  • Acquired immune deficiency syndrome. 

adj
  • Extremely annoying or frustrating. 

acquired immune deficiency syndrome

noun
  • An infectious disease, caused by HIV, that causes the gradual degeneration of the body's immune system. 

How often have the words AIDS and acquired immune deficiency syndrome occurred in a corpus of books? (source: Google Ngram Viewer )