[1] CDCP, HIV AIDS & Retrovirol Branch, Div AIDS STD & TB Lab Res, Natl Ctr Infect Dis, Atlanta, GA 30333 USA
[2] HIV AIDS Collaborat, Nonthaburi 11000, Thailand
[3] CDCP, Div HIV AIDS Prevent Surveillance & Epidemiol, Natl Ctr HIV STP & TB Prevent, Atlanta, GA 30333 USA
[4] Ctr Dis Control & Prevent, HIV Immunol & Diagnost Branch, Div AIDS STD & TB Lab Res, Natl Ctr Infect Dis, Atlanta, GA 30333 USA