Escherichia coli: placing resistance to third-generation cephalosporins and fluoroquinolones in Australia and New Zealand into perspective

At least 300 million urinary tract infections (UTIs) occur annually worldwide. Uropathogenic Escherichia coli (UPEC) are the leading cause of UTIs. The discovery of antibiotics has revolutionised modern medicine. Yet, overusing antibiotics has accelerated the emergence of antimicrobial resistance (AMR), with UPEC driving the dissemination of AMR globally. Resistance to broad-spectrum antibiotics like third-generation cephalosporins (3GCs) and fluoroquinolones threatens public health. Extended-spectrum β-lactamase (ESBL)-producing E. coli precipitate resistance, particularly when these antibiotics are used as empirical therapies against UPEC. In response, the Centers for Disease Control and Prevention in the United States have listed ESBL-producing Enterobacterales, such as E. coli as a severe threat. Additionally, the World Health Organization have classified 3GCs and fluoroquinolones as the highest priority (critically important antimicrobials), where these therapies are only recommended following susceptibility testing. The present report demonstrates the distributions of E. coli cases with resistance to 3GC and fluoroquinolones in Australia and New Zealand and contextualises trends with European reports. This investigation emphasises the value of epidemiology and the justification of evidence-based interventions using data as an essential resource for reducing resistance to our ‘first-line’ antibiotics.