[1] Univ Nottingham, Ctr Biomol Sci, Sch Life Sci, Univ Pk, Nottingham, England
[2] Univ Nottingham, Sch Sociol & Social Policy, Univ Pk, Nottingham, England
[3] Univ Nottingham, Fac Engn, Univ Pk, Nottingham, England
[4] Nottingham Univ Hosp NHS Trust, Queens Med Ctr, Dept Infect Prevent & Control, Nottingham, England
[5] Univ Nottingham, Queens Med Ctr, Sch Nursing, Nottingham, England
[6] Univ Hosp Plymouth NHS Trust, Endoscopy Unit, Plymouth, Devon, England