[1] City Hosp, Dept Microbiol & Infect Dis, Div Microbiol & Infect Dis, Nottingham NG5 1PB, England
[2] Univ Nottingham, Nottingham NG7 2RD, England
[3] Univ Toronto, Mt Sinai Hosp, Dept Microbiol, Dept Lab Med, Toronto, ON M5G 1X5, Canada
[4] Univ Toronto, Toronto Med Labs, Toronto, ON M5G 1X5, Canada