The timing is right: Evolution of AIDS-causing HIV strains is consistent with history of chloroquine use.
Parris
G E
GE
D000163:Acquired Immunodeficiency Syndrome / Q000453:epidemiology* / Q000821:virology; D002738:Chloroquine / Q000494:pharmacology / Q000627:therapeutic use*; D006678:HIV / Q000187:drug effects / Q000472:pathogenicity*; D015658:HIV Infections / Q000209:etiology / Q000235:genetics*; D006801:Humans
D002738:Chloroquine