1 Centre of Defence Pathology, Royal Centre for Defence Medicine, Queen Elizabeth Hospital Birmingham, Mindelsohn Way, Edgbaston, Birmingham, B15 2WB, UK; Chelsea and Westminster Hospital NHS Foundation Trust, 369 Fulham Road, London, SW10 9NH, UK. Electronic address: scott.pallett@nhs.net.
2 National Infection Service, Public Health England Colindale, 61 Colindale Ave, London, NW9 5EQ, UK.
3 Chelsea and Westminster Hospital NHS Foundation Trust, 369 Fulham Road, London, SW10 9NH, UK; North West London Pathology, Fulham Palace Road, London, W6 8RF, UK.
4 Chelsea and Westminster Hospital NHS Foundation Trust, 369 Fulham Road, London, SW10 9NH, UK.
5 North West London Pathology, Fulham Palace Road, London, W6 8RF, UK.
6 Chelsea and Westminster Hospital NHS Foundation Trust, 369 Fulham Road, London, SW10 9NH, UK; North West London Pathology, Fulham Palace Road, London, W6 8RF, UK; Imperial College London, NIHR Health Protection Research Unit in Healthcare Associated Infections and Antimicrobial Resistance, Du Cane Road, London, W12 0NN, UK.