1. Department of Genitourinary Medicine, Guy's and St Thomas’ NHS Foundation Trust, London SE1 9RT
2. Sexually Transmitted Bacteria Reference Laboratory, Microbiology and Epidemiology of STIs and HIV Department, Health Protection Agency Centre for Infections, 61 Colindale Avenue. London NW9 5EQ
3. Jefferiss Wing, St-Mary's Hospital, Imperial college Healthcare NHS Trust, London W2 1NY, UK