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Genomic, Antimicrobial Resistance, and Public Health Insights into spp. from Australian Chickens. Journal of clinical microbiology Due to Australia's management of antimicrobial use in poultry, particularly the discontinued use of avoparcin for nearly 20 years, it is hypothesized that vancomycin-resistant enterococci associated with human disease are not derived from poultry isolates. This study evaluated antimicrobial resistance (AMR) of five enterococcal species isolated from Australian meat chickens, genomic features of and , and the phylogenetic relationship of the poultry-derived with isolates from human sepsis cases. All enterococcal isolates from chicken ceca were subjected to antimicrobial susceptibility testing. and underwent whole-genome sequencing. was compared at the core genome level to a collection of human isolates ( = 677) obtained from cases of sepsis over a 2-year period spanning 2015 to 2016. Overall, 205 enterococci were isolated consisting of five different species. was the most frequently isolated species (37.6%), followed by (29.7%), (20%), (12.2%), and (0.5%). All isolates were susceptible to vancomycin and gentamicin, while one isolate was linezolid resistant (MIC 16 mg/liter). Core genome analysis of the demonstrated two clades consisting predominantly of human or chicken isolates in each clade, with minimal overlap. Principal component analysis for total gene content revealed three clusters comprised of -positive, -positive, and both - and -negative populations. The results of this study provide strong evidence that Australian chicken isolates are unlikely to be precursor strains to the currently circulating vancomycin-resistant strains being isolated in Australian hospitals. 10.1128/JCM.00319-19
Antibiotic resistance gene reservoir in live poultry markets. Wang Yanan,Hu Yongfei,Cao Jian,Bi Yuhai,Lv Na,Liu Fei,Liang Shihao,Shi Yi,Jiao Xinan,Gao George Fu,Zhu Baoli The Journal of infection OBJECTIVES:The heavy use of antibiotics in farm animals contributes to the enrichment and spread of antibiotic resistance genes (ARGs) in "one-health" settings. Numerous ARGs have been identified in livestock-associated environments but not in Chinese live poultry markets (LPMs). METHODS:We collected 753 poultry fecal samples from LPMs of 18 provinces and municipalities in China and sequenced the metagenomes of 130 samples. Bioinformatic tools were used to construct the gene catalog and analyze the ARG content. PCR amplification and Sanger sequencing were used to survey the distribution of mcr-1 gene in all 753 fecal samples. RESULTS:We found that a low number of genes but a high percentage of gene functions were shared among the poultry, human and pig gut gene catalogs. The poultry gut possessed 539 ARGs which were classified into 235 types. Both the ARG number and abundance were significantly higher in poultry than that in either pigs or humans. Fourteen ARG types were found present in all 130 samples, and tetracycline resistance (TcR) genes were the most abundant ARGs in both animals and humans. Moreover, 59.63% LPM samples harbored the colistin resistance gene mcr-1, and other mcr gene variants were also found. CONCLUSIONS:We demonstrated that the Chinese LPMs is a repository for ARGs, posing a high risk for ARG dissemination from food animals to humans under such a trade system, which has not been addressed before. 10.1016/j.jinf.2019.03.012
Genomic Analysis of Fluoroquinolone- and Tetracycline-Resistant Campylobacter jejuni Sequence Type 6964 in Humans and Poultry, New Zealand, 2014-2016. French Nigel P,Zhang Ji,Carter Glen P,Midwinter Anne C,Biggs Patrick J,Dyet Kristin,Gilpin Brent J,Ingle Danielle J,Mulqueen Kerry,Rogers Lynn E,Wilkinson David A,Greening Sabrina S,Muellner Petra,Fayaz Ahmed,Williamson Deborah A Emerging infectious diseases In 2014, antimicrobial drug-resistant Campylobacter jejuni sequence type 6964 emerged contemporaneously in poultry from 3 supply companies in the North Island of New Zealand and as a major cause of campylobacteriosis in humans in New Zealand. This lineage, not previously identified in New Zealand, was resistant to tetracycline and fluoroquinolones. Genomic analysis revealed divergence into 2 major clades; both clades were associated with human infection, 1 with poultry companies A and B and the other with company C. Accessory genome evolution was associated with a plasmid, phage insertions, and natural transformation. We hypothesize that the tetO gene and a phage were inserted into the chromosome after conjugation, leaving a remnant plasmid that was lost from isolates from company C. The emergence and rapid spread of a resistant clone of C. jejuni in New Zealand, coupled with evolutionary change in the accessory genome, demonstrate the need for ongoing Campylobacter surveillance among poultry and humans. 10.3201/eid2512.190267