Dr. Julie McElrath is a global leader in the study of ways to prevent and control infection with HIV, the virus that causes AIDS. As a principal investigator and director of the HIV Vaccine Trials Network’s Laboratory Center, she works to develop an effective vaccine and plays a key role in HVTN, the largest international program for testing such vaccines. Her team develops tests to predict the effectiveness of potential HIV vaccines before they move on to large-scale clinical trials, so resources can be steered to the most promising candidates. She also directs the Seattle HIV Vaccine Trials Unit, one of many international sites involved in HIV prevention trials. As head of the Vaccine and Infectious Disease Division at Fred Hutch, Dr. McElrath spearheads research on ways to protect against microbial threats and improve outcomes for people with chronic infections and cancer. Her own research is uncovering how HIV enters cells that line the genital tract and how specialized immune cells in this tissue might protect against HIV exposure. She also studies those who do not contract HIV despite repeated exposure and those whose infections do not progress for many years. When COVID-19 emerged, Dr. McElrath used her expertise to tackle this latest global pandemic.