1. * US Centers for Disease Control and Prevention (CDC), Atlanta, Georgia
2. † International Center for AIDS Care and Treatment Programs, Columbia University New York, New York
3. ‡ Division of Communicable Disease Control, Center for Infectious Diseases, California Department of Public Health, Richmond, California
4. § Methodist Hospital Research Institute, Houston, Texas
5. ¶ Texas Department of State Health Services/University of Texas Health Science Center at Tyler, Texas, USA