evidence: Researchers say they have found a second patient whose body seemingly had rid itself of the human immunodeficiency virus (HIV) that causes AIDS – supporting hope that it may be possible someday to find a way to cure more people of the virus. [...] "A sterilizing cure for HIV has previously only been observed in two patients who received a highly toxic bone marrow transplant. Our study shows that such a cure can also be reached during natural infection – in the absence of bone marrow transplants (or any type of treatment at all)," Dr. Xu Yu, of the Ragon Institute of Massachusetts General Hospital, MIT and Harvard, who was an author of the study, wrote in an email to CNN on Monday.