Antimicrobial resistance of clinical strains of Campylobacter jejuni subsp. jejuni isolated from 1985 to 1997 in Quebec, Canada.

The antimicrobial resistance of 158 Campylobacter jejuni strains isolated from humans in Quebec, Canada, from 1995 to 1997 was compared to the resistance of 47 and 86 strains of C. jejuni isolated in 1985 and 1986 and in 1992 and 1993, respectively. Of the 291 C. jejuni strains tested, no strain was resistant to erythromycin. Compared to the C. jejuni strains isolated in 1985 and 1986, the C. jejuni strains isolated in 1992 and 1993 were more resistant to tetracycline (40.7 versus 19.1%, respectively; P = 0. 01) but not to nalidixic acid or ciprofloxacin (P > 0.05). Compared to the C. jejuni strains isolated in 1992 and 1993 and in 1985 and 1986, the C. jejuni strains isolated from 1995 to 1997 were more resistant to tetracycline (55.7% versus 40.7 and 19.1%, respectively; P = 0.03 and P < 0.001, respectively) to nalidixic acid (13.9% versus 4.7 and 0%, respectively; P = 0.02 and P = 0.007, respectively), and to ciprofloxacin (12.7% versus 3.5 and 0%, respectively; P = 0.02 and P = 0.009, respectively).