Challenges to HIV Prevention — Seeking Effective Measures in the Absence of a Vaccine

In the 15 to 20 years it may take to develop and evaluate a highly efficacious vaccine, the world may be facing 20 to 60 million new HIV infections. Stephen Lagakos and Alicia Gable write that it is critical to learn how to optimize the use of multiple, partially effective biomedical and behavioral interventions in the settings and populations in which they are most effective.