[1] Mtech Access Ltd, Bicester, England
[2] Tillotts Pharm AG, Rheinfelden, Switzerland
[3] Tillotts Pharm AB, Bromma, Sweden
[4] Univ Leeds, Leeds Teaching Hosp NHS Trust, Leeds Inst Med Res, Dept Microbiol, Leeds, England
[5] Univ Leeds, Leeds Teaching Hosp NHS Trust, Dept Microbiol, Leeds LS1 3EX, England
[6] Univ Leeds, Leeds Inst Med Res, Leeds LS1 3EX, England