[1] ONTARIO MINIST HLTH,LAB SERV BRANCH,CENT PUBL HLTH LAB,TORONTO M5W 1R5,ONTARIO,CANADA
[2] ONTARIO MINIST HLTH,PUBL HLTH BRANCH,DIS CONTROL & EPIDEMIOL SERV,TORONTO M5W 1R5,ONTARIO,CANADA
[3] UNIV TORONTO,SCH GRAD STUDIES,DEPT COMMUNITY HLTH,TORONTO M5S 1A1,ONTARIO,CANADA
[4] HOSP SICK CHILDREN,DEPT BACTERIOL,TORONTO M5G 1X8,ONTARIO,CANADA
[5] UNIV WESTERN ONTARIO HOSP,DEPT CLIN MICROBIOL,LONDON N6A 5A5,ONTARIO,CANADA
[6] HLTH & WELF CANADA,LAB CTR DIS CONTROL,NATL ENTER REFERENCE CTR,OTTAWA K1A 0L2,ONTARIO,CANADA