1 Imperial College Healthcare NHS Trust, St Mary's Hospital, Praed Street, London, London W2 1NY, United Kingdom. Electronic address: james.barnacle1@nhs.net.
2 Imperial College Healthcare NHS Trust, St Mary's Hospital, Praed Street, London, London W2 1NY, United Kingdom.
3 Imperial College Healthcare NHS Trust, St Mary's Hospital, Praed Street, London, London W2 1NY, United Kingdom; Department of Infectious Disease, Imperial College London, United Kingdom.
4 Imperial College Healthcare NHS Trust, St Mary's Hospital, Praed Street, London, London W2 1NY, United Kingdom; Department of Surgery and Cancer, Imperial College London, United Kingdom.