[1] Univ London Imperial Coll Sci Technol & Med, Natl Ctr Infect Prevent & Management, London W6 8RP, England
[2] Univ Liverpool, Sch Vet Sci, Neston CH64 7TE, England
[3] Univ Liverpool, Natl Consortium Zoonosis Res, Neston CH64 7TE, England
[4] Hlth Protect Agcy, Microbiol Serv Colindale, Lab Healthcare Associated Infect, London, England
[5] Univ Birmingham, Sch Med, Sch Immun & Infect, Edgbaston B15 2TT, England
[6] Heart England NHS Fdn Trust, W Midlands Publ Hlth Lab, Birmingham B9 5SS, W Midlands, England