I remember at the time he announced that he had HIV that he said his wife and their unborn child were uninfected. He was infected through unprotected sex. How did his wife remain unaffected? His wife was pregnant with a child they conceived in September of 1991. He announced found out he was HIV-positive the first week of that November. That gives him a about a 50-day window in which he could have contracted the virus after having conceived the child. Would an HIV test from that era be able to confirm he was positive with such a short window? Could he have conceived a child while HIV positive, without infected the child or mother?
Yes. Transmission doesn’t occur in every sexual event.
Even an HIV+ mom will not transmit the virus to her child in most cases. The mother–>child transmission rate can be reduced further through a number of interventions.
According to Wikipedia, the transmission rates for penile-vaginal intercourse is only about 0.1% per interaction. They’d have to have unprotected sex 600+ times for her to have a 50% chance of getting it.
On average. More chance of transmission if either has, oh, active herpes or other cuts or sores, if they have vigorous sex, if they have anal sex, if she’s immunosuppressed for some reason, etc.