Professor Quarraisha Abdool Karim is one of the world’s leading AIDS researchers and has made pioneering contributions to understanding the HIV epidemic in young people, especially among young women. She joined us for a two-part series to explain her latest research into epidemic hot spots in KwaZulu-Natal in South Africa, focusing on both the structural and biological risk factors that facilitate the spread of HIV in young women. In Part 2, she describes her recent findings about biological factors that can simultaneously increase a woman’s risk of HIV acquisition and decrease the efficacy of HIV prevention tools. Hosted by Janet Fleischman. Produced by Alex Bush. Edited by Ribka Gemilangsari.