title: 40 percent of US citizens do not know how HIV is transmitted.
mesh_terms: D000163:Acquired Immunodeficiency Syndrome / Q000517:prevention & control / Q000635:transmission*; D015658:HIV Infections / Q000517:prevention & control / Q000635:transmission*; D007722:Health Knowledge, Attitudes, Practice; D006801:Humans; D011639:Public Opinion; D014481:United States