1. Department of Epidemiology, Fielding School of Public Health, University of California, Los Angeles, Los Angeles, CA, USA
2. David Geffen UCLA School of Medicine, University of California, Los Angeles, Los Angeles, CA, USA
3. Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
4. Department of Medicine, University of Pittsburgh, Pittsburgh, PA, USA
5. Division of Infectious Diseases, Feinberg School of Medicine of Northwestern University, Chicago, IL, USA
6. Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA