Analysis of Resistance Gene Prevalence in Whole-Genome Sequenced Enterobacteriales from Brazil

Enterobacteriales is an order of bacteria responsible for community and hospital-acquired infections related to high rates of antimicrobial resistance and increased treatment costs, morbidity, and mortality globally. The aims of this study were to analyze the frequency of the resistance genes detected and distribution over the years and sources of isolation in sequenced Enterobacteriales strains isolated in Brazil and available at the Pathogen Detection website. The presence of resistance genes was analyzed in 1,507 whole-genome sequenced strains of 19 Enterobacteriales species. A total of 58.0% of the strains presented resistance genes to at least one antimicrobial class and 684 strains presented a multidrug-resistant (MDR) profile. Resistance genes to 14 classes of antimicrobials were detected. Aminoglycosides presented the most prevalent and diverse resistance genes, while the sulfonamide resistance gene, sul2, was the most prevalent among the strains studied. The presence of resistance genes from 14 different antimicrobial classes, the high levels of MDR strains, and the detection of genes related to clinical and veterinary-used drugs reinforce the necessity of more efficient control measures. Moreover, it warns for the necessity of the rational use of antimicrobials in veterinary and clinical situations in Brazil, since contaminated food may act as a vehicle for human infections.