Volume 15, Number 5—May 2009
Possible Seasonality of Clostridium difficile in Retail Meat, Canada
|Type†||% (no.)||Toxin genes‡||tcdC deletion||Toxinotype||PFGE§||Product–culture||Month||Province|
|M26||23.1 (3)||A–B–, cdtB–||NA||Nontypeable||Unnamed||VC–C3||Feb||QC|
|077¶||23.1 (3)||A+B+, cdtB–||No||0||NAP2||GB–C3||Jan||QC|
|J¶||23.1 (3)||A+B+, cdtB+||18 bp||III||NAP1||GB–C4||May||ON|
|014¶||15.4 (2)||A+B+, cdtB–||No||0||NAP4||GB–C1||May||QC|
|C||7.7 (1)||A+B+, cdtB–||No||–||–||GB–C1||Jan||ON|
|F||7.7 (1)||A-B+, cdtB–||No||VIII||NAP9||GB–C2||Jan||QC|
|H||7.7(1)||A+B+, cdtB-||No||0||Unnamed||GB – C1||Jun||QC|
|K||7.7(1)||A+B+, cdtB+||18 bp||III||NAP1-r||VC–C2||Aug||QC|
*PFGE, pulsed-field gel electrophoresis; NA, not amplified because it lacks pathogenicity locus; VC, veal chops; GB, ground beef; C1, rinsate/TCDMNB; C2, meat/TCDMNB; C3, meat/TCDMNB duplicate; C4, meat/TCFFB; QC, Québec; ON, Ontario; SK, Saskatchewan; –, not performed.
†Bidet’s PCR ribotyping method (9); 077 and 014; representative ribotypes with international nomenclatures assigned by Dr Jon Brazier, University of Wales, Wales, in a previous study (11). M26, non-toxigenic Canadian meat ribotype lacking pathogenicity locus (pers. com., M. Rupnik, University of Maribor, Slovenia) (5).
‡A, B; tcdA and tcdB genes. cdtB, binding segment of binary toxin; – and + superscripts indicate absence or presence of the gene. tcdC gene: no deletions (≈345 bp); 18 bp, deletion type B/C (8).
§Nomenclature at the Centers for Disease and Control and Prevention, Atlanta, GA, USA. NAP1, North America PFGE type 1.
¶Meat PCR ribotypes matching concurrent local and international human ribotypes (2,3). Note that 28 C. difficile isolates initially identified were grouped into 15 strains based on molecular characteristics and source of origin; 2 meat samples simultaneously harbored 2 strains.