[1] St Thomas Hosp, Infect Sci, Viapath, London, England
[2] Brighton & Sussex Univ Hosp NHS Trust, Dept Virol, Frontier Pathol, Brighton, E Sussex, England
[3] Brighton & Sussex Univ Hosp NHS Trust, Dept GUM HIV, Brighton, E Sussex, England
[4] Guys & St Thomas NHS Fdn Trust, Dept GUM HIV, London, England