In recent years, Campylobacter has become increasingly resistant to antibiotics, especially those first-choice drugs used to treat campylobacteriosis. Studies in South America have reported cases of antibiotic-resistant Campylobacter in several countries, mainly in Brazil. To understand the current frequency of antibiotic-resistant Campylobacter in humans, farm animals, and food of animal origin in South America, we systematically searched for different studies that have reported Campylobacter resistance. The most commonly reported species were C. jejuni and C. coli. Resistance to ciprofloxacin was found to be ubiquitous in the isolates. Nalidixic acid and tetracycline showed a significantly expressed resistance. Erythromycin, the antibiotic of first choice for the treatment of campylobacteriosis, showed a low rate of resistance in isolates but was detected in almost all countries. The main sources of antibiotic-resistant Campylobacter isolates were food of animal origin and farm animals. The results demonstrate that resistant Campylobacter isolates are disseminated from multiple sources linked to animal production in South America. The level of resistance that was identified may compromise the treatment of campylobacteriosis in human and animal populations. In this way, we are here showing all South American communities the need for the constant surveillance of Campylobacter resistance and the need for the strategic use of antibiotics in animal production. These actions are likely to decrease future difficulties in the treatment of human campylobacteriosis.

Aims The aim of this study was to analyze and compare the prevalence and distribution of resistance genes in Escherichia coli genomes isolated from human clinical samples and animal-based foods worldwide. Methods and results We download from NCBI Pathogen Detection Database the corresponding metadata of the 7,123 E. coli genome to access the information about the antimicrobial resistance gene content. The geographic location and the source of isolation were also obtained and compiled with the antimicrobial resistance gene for statistical analysis, results and discussion. Our criteria considered four groups for analyzing the antimicrobial resistance gene distribution. The first group of genomes from invasive clinical human (ICH) samples from countries with Human Development Index (HDI) ≥ 0.850; the second group of ICH from countries with an HDI ≤ 0.849; the third group of animal-based foods (ABF) from countries with HDI ≥ 0.850 and the fourth group of ABFs from countries with HDI ≤ 0.849. The most prevalent genes in the first group were blaCTX-M-134 (96.53%) and blaCTX-M-27 (86.35%). In the second group, ere(A) (95.96%), soxS (94.49%), qepA8 (90.81%), blaCTX-M-15 (85.66%), and fosA3 (80.88%). In the third group, the most frequently detected were aadA12 (98.5%), ant(3”) (89.92%), and blaCARB-2 (87.2%). In the fourth group, aadA12 and aac(3)-IV were identified in 100% of the analyzed genomes. Conclusions It was clear that the use of aminoglycosides in animal production is increasing the selective pressure on micro-organisms in both groups of countries since genes linked to aminoglycoside resistance are related to E. coli from ABF samples. The genomic profile of E. coli from HDI ≥ 0.850 countries indicates a selective pressure aimed at cephalosporins given the high prevalence in both sources.

Salmonella Isangi is an infrequent serovar that has recently been reported in several countries due to nosocomial infections. A considerable number of reports indicate Salmonella Isangi multidrug resistance, especially to cephalosporins, which could potentially pose a risk to public health worldwide. Genomic analysis is an excellent tool for monitoring the emergence of microorganisms and related factors. In this context, the aim of this study was to carry out a genomic analysis of Salmonella Isangi isolated from poultry in Brazil, and to compare it with the available genomes from the Pathogen Detection database and Sequence Read Archive. A total of 142 genomes isolated from 11 different countries were investigated. A broad distribution of extended-spectrum beta-lactamase (ESBL) genes was identified in the Salmonella Isangi genomes examined (blaCTX-M-15, blaCTX-M-2, blaDHA-1, blaNDM-1, blaOXA-10, blaOXA-1, blaOXA-48, blaSCO-1, blaSHV-5, blaTEM-131, blaTEM-1B), primarily in South Africa. Resistome analysis revealed predicted resistance to aminoglycoside, sulfonamide, macrolide, tetracycline, trimethoprim, phenicol, chloramphenicol, and quaternary ammonium. Additionally, PMQR (plasmid-mediated quinolone resistance) genes qnr19, qnrB1, and qnrS1 were identified, along with point mutations in the genes gyrAD87N, gyrAS83F, and gyrBS464F, which confer resistance to ciprofloxacin and nalidixic acid. With regard to plasmids, we identified 17 different incompatibility groups, including IncC, Col(pHAD28), IncHI2, IncHI2A, IncM2, ColpVC, Col(Ye4449), Col156, IncR, IncI1(Alpha), IncFIB (pTU3), Col(B5512), IncQ1, IncL, IncN, IncFIB(pHCM2), and IncFIB (pN55391). Phylogenetic analysis revealed five clusters grouped by sequence type and antimicrobial gene distribution. The study highlights the need for monitoring rare serovars that may become emergent due to multidrug resistance.