Population-based epidemiology of Escherichia coli ST1193 causing blood stream infections in a centralized Canadian region.

Escherichia coli ST1193 is an emerging global clone associated with fluoroquinolone resistance. A population-based study described genomics, clinical factors, susceptibility patterns, and incidence rates of ST1193 (n = 69) causing incident blood stream infections in a centralized Canadian region 2016-18. ST1193 was responsible for community-acquired upper urinary tract infections among the elderly. The incidence rate (IR) per 100,000 person-years among Calgary residents increased from 1.0 (95%confidence interval [95%CI] 0.7-1.5) in 2016, to 1.7 (95%CI 1.3-2.3) in 2018 (p = 0.05). This was mainly due to the significant increase of ST1193 blood stream infections among female long-term care (LTC) residents. ST1193 IR with blaCTX-Ms was 3.18 times higher in 2018 than in 2016 (CI 95% 0.98-13.49). We identified a ST1193 isolate with only a parC S80I mutation that is different from previously published data. The population-based study identified a significant increase over a 2-year period of E. coli ST1193 blood stream infections among elderly females residing in LTC centers. There was also a notable increase of ST1193 with bla CTX-Ms in 2018. The rapid emergence of ST1193 is concerning and adding to the public health burden of multidrug resistant E. coli blood stream infections in Calgary.