When I first arrived in beautiful Zimbabwe, it was difficult to understand that 35 percent of the population is HIV positive. It really wasn't until I was invited to the homes of people that I started to understand the human toll of the epidemic. For instance, this is Herbert with his grandmother. When I first met him, he was sitting on his grandmother's lap. He has been orphaned, as both of his parents died of AIDS, and his grandmother took care of him until he too died of AIDS. He liked to sit on her lap because he said that it was painful for him to lay in his own bed. When she got up to make tea, she placed him in my own lap and I had never felt a child that was that emaciated. Before I left, I actually asked him if I could get him something. I thought he would ask for a toy, or candy, and he asked me for slippers, because he said that his feet were cold.

This is Joyce who's -- in this picture -- 21. Single mother, HIV positive. I photographed her before and after the birth of her beautiful baby girl, Issa. And I was last week walking on Lafayette Street in Manhattan and got a call from a woman who I didn't know, but she called to tell me that Joyce had passed away at the age of 23. Joyce's mother is now taking care of her daughter, like so many other Zimbabwean children who've been orphaned by the epidemic. So a few of the stories. But with every picture, there are individuals who have full lives and stories that deserve to be told. All these pictures are from Zimbabwe.

Chris Anderson: Kirsten, will you just take one minute, just to tell your own story of how you got to Africa?

Kirsten Ashburn: Mmm, gosh.

CA: Just --

KA: Actually, I was working at the time, doing production for a fashion photographer. And I was constantly reading the New York Times, and stunned by the statistics, the numbers. It was just frightening. So I quit my job and decided that that's the subject that I wanted to tackle. And I first actually went to Botswana where I spent a month -- this is in December 2000 -- then went to Zimbabwe for a month and a half, and then went back again this March 2002 for another month and a half in Zimbabwe.

CA: That's an amazing story, thank you.

KB: Thanks for letting me show --