[1] Hlth Protect Agcy, Virus Reference Dept, Ctr Infect, London NW9 5EQ, England
[2] Hlth Protect Agcy, HIV STI Dept, Hlth Protect Serv Colindale, London NW9 5EQ, England
[3] Hlth Protect Agcy, Appl & Funct Genom Unit, Ctr Infect, London NW9 5EQ, England
[4] Homerton Univ Hosp NHS Trust, London, England
[5] Univ London, Ctr Canc Prevent, Wolfson Inst Preventat Med, London, England