Derek Macallan is Professor of Infectious Diseases and Medicine at St George's, University of London and a Consultant Physician in St George's Healthcare NHS Trust. As part of the Clinical Infection Unit (CIU), he cares for patients admitted with a variety of infection-related illnesses, including TB, HIV, travel-related disease, meningitis and PUO (pyrexia of unknown origin). CIU patients are normally admitted to McEntee Ward, the specialist infectious diseases ward at St George's Hospital. Prof Macallan also looks after patients with HIV in the Courtyard Clinic at St George's where his special interests include TB-HIV co-infection and HIV-hepatitis co-infection.