Positive Association between the Use of Quinolones in Food Animals and the Prevalence of Fluoroquinolone Resistance in <i>E. coli</i> and <i>K. pneumoniae, A. baumannii and P. aeruginosa</i>: A Global Ecological Analysis

(1) Background: It is unclear what underpins the large global variations in the prevalence of fluoroquinolone resistance in Gram-negative bacteria. We tested the hypothesis that different intensities in the use of quinolones for food-animals play a role. (2) Methods: We used Spearman’s correlation to assess if the country-level prevalence of fluoroquinolone resistance in human infections with Acinetobacter baumannii, Escherichia coli, Klebsiella pneumoniae and Pseudomonas aeruginosa was correlated with the use of quinolones for food producing animals. Linear regression was used to assess the relative contributions of country-level quinolone consumption for food-animals and humans on fluoroquinolone resistance in these 4 species. (3) Results: The prevalence of fluoroquinolone resistance in each species was positively associated with quinolone use for food-producing animals (E. coli [ρ = 0.55; p K. pneumoniae [ρ = 0.58; p A. baumanii [ρ = 0.54; p = 0.004]; P. aeruginosa [ρ = 0.48; p = 0.008]). Linear regression revealed that both quinolone consumption in humans and food animals were independently associated with fluoroquinolone resistance in E. coli and A. baumanii. (4) Conclusions: Besides the prudent use of quinolones in humans, reducing quinolone use in food-producing animals may help retard the spread of fluoroquinolone resistance in various Gram-negative bacterial species.