[1] Inst Pasteur, Dakar, Senegal
[2] Inst Pasteur, Unite Regulat Infect Retrovirales, F-75015 Paris, France
[3] Univ Paris 05, F-75270 Paris 06, France
[4] Hop St Vincent de Paul, Virol Lab, F-75674 Paris, France
[5] Univ Paris 05, Inst Cochin, UMR CNRS 8104, Unite INSERM 567, F-75270 Paris 06, France
[6] Univ Paris 07, F-75221 Paris 05, France
[7] Univ Insubria, Varese, Italy