The Partners in Prevention (PIP) HIV/HSV Study enrolled people who were in serodiscordant relationships (where one partner in the couple was HIV positive and the other was HIV negative). The PIP team needed to explain the concept of serodiscordance in a way that could be understood by the study’s participants in eastern and southern Africa. The team used an image of two baobab trees (left), one of which is infested with termites that can destroy one or both trees. Partners in Prevention used the illustration to show that HIV can infect one or both partners, but that it cannot be diagnosed without testing.