Box Surgery, Wiltshire, UK. gruffbox@btinternet.com. Thame Health Centre, Thame, UK. Virgin Care, Farnham Hospital, Farnham, UK. Respiratory Department, Royal Infirmary of Edinburgh, Edinburgh, UK. Leicestershire Partnership NHS Trust, Leicester, UK. Department of Respiratory Medicine, University Hospitals Birmingham NHS Foundation Trust (Queen Elizabeth Hospital), Birmingham, UK. Host Defence Unit, Department of Respiratory Medicine, Royal Brompton Hospital and Harefield NHS Foundation Trust, London, UK. Glenfield Hospital, Leicester, UK. Department of Clinical Sciences, Brunel University London, London, UK. Royal Brompton Hospital, London, UK. British Thoracic Society, London, UK. Respiratory Medicine, Royal Infirmary of Edinburgh, and University of Edinburgh, Edinburgh, UK.