Fj. Schmitz et al., Increased prevalence of class I integrons in Escherichia coli, Klebsiella species, and Enterobacter species isolates over a 7-year period in a Germanuniversity hospital, J CLIN MICR, 39(10), 2001, pp. 3724-3726
The prevalence of integrons in five enterobacterial species was analyzed in
900 blood culture isolates from 1993, 1996, and 1999. Remarkably, the prev
alence increased from 4.7% in 1993 to 9.7% in 1996 and finally to 17.4% in
1999 (P < 0.01). Within 7 years the combined percentage of P1 strong promot
ers and PI weak plus P2 active promoters with high transcription efficacies
has increased from 23.1 to 33.3 and finally 60% (P < 0.05).