There's so much stigma around HIV/AIDS. It's a challenging issue, and the people that already have been tested and know their status find it very, very hard to disclose their status, to live with that virus, and to even seek out the kind of information they need. This experience of going to South Africa a decade ago really woke me up to the scale of the HIV/AIDS pandemic in sub-Saharan Africa, how it was affecting women and their children. I haven't been able to walk away from it.