About the Authors
Division of HIV/AIDS Prevention, National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
STI/HIV Division, Chicago Department of Public Health, Chicago, Illinois, United States of America
HIV Epidemiology Program, Los Angeles County Department of Public Health, Los Angeles, California, United States of America
The authors have declared that no competing interests exist.
Conceived and designed the experiments: HIH NB. Analyzed the data: HIH LE. Contributed reagents/materials/analysis tools: LE YWH. Wrote the paper: HIH NB. Interpretation of data: LE YWH.