[1] Project RETRO CI, Virol Lab, Abidjan 01, Cote Ivoire
[2] Inst Trop Med, B-2000 Antwerp, Belgium
[3] Ctr Dis Control & Prevent, Div HIV AIDS Prevent, Atlanta, GA USA
[4] Ctr Dis Control & Prevent, Global AIDS Program, Natl Ctr HIV STD & TB Prevent, Atlanta, GA USA