[1] Dist Gen Hosp, Dept Med Microbiol, Eastbourne, E Sussex, England
[2] Queens Univ Belfast, Belfast City Hosp, Belfast BT7 9AB, Antrim, North Ireland
[3] Queens Univ Belfast, Belfast City Hosp, Dept Bacteriol, No Ireland Publ Hlth Lab, Belfast BT7 9AB, Antrim, North Ireland
[4] Queens Univ Belfast, Belfast City Hosp, No Ireland Reg Adult Cyst Fibrosis Ctr, Dept Resp Med, Belfast BT7 9AB, Antrim, North Ireland