Was watching a UK documentary1 about Charles Darwin the other day. In it Richard Dawkins was interviewing a prostitute in Kenya who apparently has immunity to HIV. There's a significant percentage of the population infected with HIV, a high rate of clients per day for Nairobi prostitutes who commonly don't use condoms so the odds against prostitutes there contracting HIV are really low. So prostitutes like this lady are current and real life examples of humans evolving purely by natural selection to beat some virus (i.e. lots and lots of people die but only the one with genetic advantage survives to reproduce)!
Kind of ironic that the very occupation that's highly likely to get you infected with HIV is one that potentially reveals the genetic sequence needed to avoid it.