Although there have been reports of women transmitting the human immunodeficiency virus to other women via sexual activity in the past, they have been difficult to prove. For nearly all the cases, other risk factors were present — including recent sexual contact with a man, intravenous drug use, tattooing, piercing or other potentially risky behaviors.
But this time, the case seems pretty iron-clad.
As outlined in a paper published by the CDC this week, the two women involved were in a monogamous relationship for six months. At the start of their relationship one of the women was HIV-positive, the other was not. The woman who began the relationship HIV negative said it had been 10 years since she had had sex with a man. She did not use intravenous drugs, or get tattoos or acupuncture or transfusions or transplants.