TABLE 1.

Characteristics of the E. coli strains harboring pC15-1a used in this studya

StrainDate of isolationLocationbPFGE profilecPlasmidResistance phenotyped
N00-06662000LTC outbreakA1pC15-1aAmp Cfz Cro Cip Gen Tob
ESBL351 Dec. 1999VGHB1pC15-1a variantAmc Amp Cfz Caz Cro Cip Gen Tzp Tob Sxt
ESBL1233 April 2000VGHC1pC15-2aAmp Cfz Cro Cip Sxt
ESBL30420 May 2000VGHD1pC15-1aAmp Cfz Cro Cip Gen Tob Sxt
ESBL36130 Aug. 2000VGHE1pC15-1aAmp Cfz Cro Gen Tob Sxt
ESBL37014 Sept. 2000VGHF1pC15-1aAmp Cfz Cro Cip Gen Tob Sxt
ESBL37317 Sept. 2000VGHF1NDeAmc Amp Cfz Cro Cip Gen Tob Sxt
ESBL37418 Sept. 2000VGHF1NDAmp Cfz Cro Cip Gen Tob Sxt
ESBL4757 May 2000UHNG1pC15-1aAmc Amp Cfz Cro Cip Gen Tob Sxt
ESBL48027 Sept. 2000UHNH1pC15-2bAmp Cfz Cro Cip Gen Tob
  • a All strains were positive by PCR analysis for CTX-M-, TEM-, and OXA-1-type genes and contained beta-lactamases with pls of 5.4, 7.4, and 8.6 as determined by isoelectric focusing.

  • b LTC outbreak; long-term-care outbreak, Toronto region. VGH, Vancouver General Hospital; UHN, University Health Network, Toronto, Ontario, Canada.

  • c The same letter-number combination means that fingerprints were indistinguishable, A different letter-number combination means that fingerprints had >7 band differences.

  • d Abbreviations indicate drug resistance as follows: Amc, amoxicillin-clavulanic acid; Amp, ampicillin; Cfz, cefazolin; Caz, ceftazidime; Cro, ceftriaxone; Cip, ciprofloxacin; Gen, gentamicin; Tzp, piperacillin-tazobactam; Tob, tobramycin; Sxt, trimethoprim-sulfamethoxazole.

  • e ND, not done.