acquired immune deficiency syndrome vs herpes simplex

acquired immune deficiency syndrome

noun

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

herpes simplex

noun

  • A viral disease caused by Human herpesvirus 1 or Human herpesvirus 2 in genus Simplexvirus. 

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