Increase in the community circulation of ciprofloxacin-resistant Escherichia coli despite reduction in antibiotic prescriptions.

The alarming rise of bacteria causing infections that are difficult to treat with antibiotics, known as multidrug-resistant bacteria, is a major problem in medicine. The reduction in the use of antibiotics has been encouraged to control the spread of antibiotic-resistant bacteria. Some multidrug-resistant bacteria reside in the gut of healthy individuals and can cause various forms of urinary tract infections (UTIs). Ciprofloxacin is an antibiotic that was widely used to treat UTIs, but strong recommendations to reduce its prescription have been recently introduced. We compared the presence of bacteria in the gut that could not be killed by ciprofloxacin in women aged 50 and above who do not use antibiotics and reside in the Seattle area. Despite a nearly three-fold drop in the prescription of ciprofloxacin between 2015 and 2021, antibiotic-resistant bacteria in the gut were found more frequently, affecting one in five women. Our study demonstrates that antibiotic-resistant bacteria continue to be present even when antibiotic prescriptions are reduced, demonstrating the need to undertake further similar studies.