[1] Kings Coll Hosp, Guys Kings & St Thomas Sch Med, Weston Educ Ctr, Dept HIV & Genitourinary Med, London SE5 9RT, England
[2] Chelsea & Westminster Hosp, Dept HIV & Genitourinary Med, London, England
[3] John Radcliffe Hosp, Inst Mol Med, Human Immunol Unit, Oxford OX3 9DU, England