[1] Ugandan Virus Res Inst, Med Res Council, Uganda Res Unit AIDS, Entebbe, Uganda
[2] Univ York, Dept Hlth Sci, York YO10 5DD, N Yorkshire, England
[3] London Sch Hyg & Trop Med, London WC1, England
[4] Frederick Natl Lab Canc Res, Viral Oncol Sect, AIDS & Canc Virus Program, SAIC Frederick, Frederick, MD USA
[5] Int Agcy Res Canc, Lyon, France