#Quinolone nonsusceptibility among #enteric #pathogens isolated from #international #travelers – #FoodNet and #NARMS, 10 #US sites, 2004 – 2014 (PLOS One, abstract)

[Source: PLOS One, full page: (LINK). Abstract, edited.]


Quinolone nonsusceptibility among enteric pathogens isolated from international travelers – Foodborne Diseases Active Surveillance Network (FoodNet) and National Antimicrobial Monitoring System (NARMS), 10 United States sites, 2004 – 2014

Julian E. Grass , Sunkyung Kim, Jennifer Y. Huang, Stephanie M. Morrison, Andre E. McCullough, Christy Bennett, Cindy R. Friedman, Anna Bowen


Published: December 4, 2019 / DOI: https://doi.org/10.1371/journal.pone.0225800



Gastrointestinal illnesses are the most frequently diagnosed conditions among returning U.S. travelers. Although most episodes of travelers’ diarrhea do not require antibiotic therapy, fluoroquinolones (a type of quinolone antibiotic) are recommended for treatment of moderate and severe travelers’ diarrhea as well as many other types of severe infection. To assess associations between quinolone susceptibility and international travel, we linked data about isolate susceptibility in NARMS to cases of enteric infections reported to FoodNet. We categorized isolates as quinolone-nonsusceptible (QNS) if they were resistant or had intermediate susceptibility to ≥1 quinolone. Among 1,726 travel-associated infections reported to FoodNet with antimicrobial susceptibility data in NARMS during 2004–2014, 56% of isolates were quinolone-nonsusceptible, of which most (904/960) were Campylobacter. International travel was associated with >10-fold increased odds of infection with quinolone-nonsusceptible bacteria. Most QNS infections were associated with travel to Latin America and the Caribbean (390/743; 52%); however, the greatest risk of QNS infection was associated with travel to Africa (120 per 1,000,000 passenger journeys). Preventing acquisition and onward transmission of antimicrobial-resistant enteric infections among travelers is critical.


Citation: Grass JE, Kim S, Huang JY, Morrison SM, McCullough AE, Bennett C, et al. (2019) Quinolone nonsusceptibility among enteric pathogens isolated from international travelers – Foodborne Diseases Active Surveillance Network (FoodNet) and National Antimicrobial Monitoring System (NARMS), 10 United States sites, 2004 – 2014. PLoS ONE 14(12): e0225800. https://doi.org/10.1371/journal.pone.0225800

Editor: Adriano Gianmaria Duse, School of Pathology, National Health Laboratory Service (NHLS) and University of the Witwatersrand, South Africa, SOUTH AFRICA

Received: June 25, 2019; Accepted: November 12, 2019; Published: December 4, 2019

This is an open access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.

Data Availability: All relevant data are within the manuscript and its Supporting Information files.

Funding: The author(s) received no specific funding for this work.

Competing interests: The authors have declared that no competing interests exist.

Keywords: Antibiotics; Drugs Resistance; Quinolones; Travelers; USA.


#Meningococcal #quinolone #resistance originated from several commensal #Neisseria species (Antimicrob Agents Chemother., abstract)

[Source: Antimicrobial Agents and Chemotherapy, full page: (LINK). Abstract, edited.]

Meningococcal quinolone resistance originated from several commensal Neisseria species

Mingliang Chen, Chi Zhang, Xi Zhang, Min Chen

DOI: 10.1128/AAC.01494-19



Quinolone resistance is increasing in Neisseria meningitidis, with high prevalence in China (>70%), but its origin remains unknown. The aim of this study was to investigate donors of mutation-harboring gyrA alleles in N. meningitidis. A total of 198 N. meningitidis and 293 commensal Neisseria isolates were collected between 2005 and 2018 in Shanghai, China. Minimum inhibitory concentrations (MICs) of ciprofloxacin were determined using agar dilution method. Resistance-associated genes gyrA and parC were sequenced for all isolates, while a few isolates were performed Illumina sequencing. The prevalence of quinolone resistance in N. meningitidis and commensal Neisseria was 67.7% (134/198) and 99.3% (291/293), respectively. All 134 quinolone-resistant N. meningitidis isolates possessed mutations in T91 (n=123) and/or D95 (n=12) of GyrA, with 7 isolates also harboring ParC mutations and exhibiting higher MICs. Phylogenetic analysis of the gyrA sequence identified six clusters. Among the 71 mutation-harboring gyrA alleles represented by 221 N. meningitidis isolates and genomes (n=221), 12 alleles (n=103, 46.6%) were included in N. meningitidis cluster, while 20 alleles (n=56) in N. lactamica cluster, 27 alleles (n=49) in N. cinerea cluster, and 9 alleles (n=10) in N. subflava cluster. Genomic analyses identified the exact N. lactimica donors of seven mutation-harboring gyrA alleles (gyrA92, gyrA97, gyrA98, gyrA114, gyrA116, gyrA151, and gyrA230) and the N. subflava donor isolate of gyrA171, with recombinant fragment ranging from 634 to 7499 bp. Transformation of gyrA fragments from these donor strains into a meningococcal isolate increased its ciprofloxacin MIC from 0.004 μg/ml to 0.125 or 0.19 μg/ml, and to 0.5 μg/ml with further transformation of an additional ParC mutation. Over half of quinolone-resistant N. meningitidis isolates acquired resistance by horizontal gene transfer from three commensal Neisseria species. Quinolone resistance in N. meningitidis increases in a stepwise manner.

Copyright © 2019 American Society for Microbiology. All Rights Reserved.

Keywords: Antibiotics; Drugs Resistance; Neisseria meningitidis; Meningococcal meningitis; Quinolones.


Comparison of the inoculum size effects of #antibiotics on IMP-6 β-lactamase-producing #Enterobacteriaceae co-harboring #plasmid-mediated #quinolone #resistance genes (PLOS One, abstract)

[Source: PLOS One, full page: (LINK). Abstract, edited.]


Comparison of the inoculum size effects of antibiotics on IMP-6 β-lactamase-producing Enterobacteriaceae co-harboring plasmid-mediated quinolone resistance genes

Yoshihiko Ogawa, Ryuichi Nakano , Kei Kasahara, Tomoki Mizuno, Nobuyasu Hirai, Akiyo Nakano, Yuki Suzuki, Naoki Kakuta, Takashi Masui, Hisakazu Yano, Keiichi Mikasa


Published: November 13, 2019 / DOI: https://doi.org/10.1371/journal.pone.0225210



Almost all cases of carbapenemase-producing Enterobacteriaceae infections in Japan are caused by blaIMP-positive Enterobacteriaceae (especially blaIMP-6) and infections caused by other types of carbapenemase-producing Enterobacteriaceae are quite rare. We examined drug resistance genes co-harboring with blaIMP-6 and their inoculum size effects. We screened β-lactamase genes, plasmid-mediated quinolone resistance (PMQR) genes, and aminoglycoside-modifying enzyme genes by PCR and performed sequencing for 14 blaIMP-6-positive Enterobacteriaceae. Further, all PMQR-positive isolates were submitted to conjugation and inoculum effect evaluation. Our data showed that 13 of the 14 isolates harbored CTX-M-2 and one co-harbored CTX-M-2 and CTX-M-1 as extended-spectrum β-lactamases. All isolates carried one or more PMQRs; aac(6’)-Ib-cr was the most prevalent (92.8%), and was followed by oqxA (64.3%), qnrS (50%), oqxAB (21.4%), and qnrB (14.3%). However, Klebsiella pneumoniae contains chromosomal OqxAB. Inoculum size effects were significant in all strains for meropenem, 13 strains for imipenem, 7 for levofloxacin, and 3 for amikacin. We observed that 11 of the experimental strains (100%), 8 strains (72.7%), and 1 strain showed inoculum size effects for meropenem, imipenem, and amikacin, respectively. However, four strains harbored qnr genes and two strains harbored qnr genes and QRDR mutations concurrently; no inoculum size effect was seen for levofloxacin. The blaIMP-6-positive Enterobacteriaceae that we studied was found to harbor at least one plasmid-mediated drug resistance gene. The inoculum size effect for carbapenems was thought to be mainly due to IMP-6-type metallo-β-lactamase; however qnrB and qnrS also had a minimal impact on the inoculum size effect for levofloxacin.


Citation: Ogawa Y, Nakano R, Kasahara K, Mizuno T, Hirai N, Nakano A, et al. (2019) Comparison of the inoculum size effects of antibiotics on IMP-6 β-lactamase-producing Enterobacteriaceae co-harboring plasmid-mediated quinolone resistance genes. PLoS ONE 14(11): e0225210. https://doi.org/10.1371/journal.pone.0225210

Editor: Shampa Anupurba, Institute of Medical Sciences, Banaras Hindu University, INDIA

Received: July 22, 2019; Accepted: October 29, 2019; Published: November 13, 2019

Copyright: © 2019 Ogawa et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Data Availability: All relevant data are within the manuscript.

Funding: This study was supported by JSPS KAKENHI (grant number: 17K10027 and 16K09940).

Competing interests: The authors have declared that no competing interests exist.

Keywords: Antibiotics; Drugs Resistance; Carbapenem; Beta-lactams; Quinolones; Enterobacteriaceae.


#Plasmid-mediated #quinolone #resistance: Mechanisms, detection, and #epidemiology in the #Arab countries (Infect Genet Evol., abstract)

[Source: US National Library of Medicine, full page: (LINK). Abstract, edited.]

Infect Genet Evol. 2019 Sep 4:104020. doi: 10.1016/j.meegid.2019.104020. [Epub ahead of print]

Plasmid-mediated quinolone resistance: Mechanisms, detection, and epidemiology in the Arab countries.

Yassine I1, Rafei R2, Osman M2, Mallat H2, Dabboussi F2, Hamze M1.

Author information: 1 Laboratoire Microbiologie Santé et Environnement (LMSE), Doctoral School of Sciences and Technology, Faculty of Public Health, Lebanese University, Tripoli, Lebanon. Electronic address: mhamze@monzerhamze.com. 2 Laboratoire Microbiologie Santé et Environnement (LMSE), Doctoral School of Sciences and Technology, Faculty of Public Health, Lebanese University, Tripoli, Lebanon.



Quinolones are an important antimicrobial class used widely in the treatment of enterobacterial infections. Although there are multiple mechanisms of quinolone resistance, attention should be paid to plasmid-mediated genes due to their ability to facilitate the spread of quinolone resistance, the selection of mutants with a higher-level of quinolone resistance, and the promotion of treatment failure. Since their discovery in 1998, plasmid-mediated quinolone resistance (PMQR) mechanisms have been reported more frequently worldwide especially with the extensive use of quinolones in humans and animals. Nevertheless, data from the Arab countries are rare and often scattered. Understanding the prevalence and distribution of PMQR is essential to stop the irrational use of quinolone in these countries. This manuscript describes the quinolone resistance mechanisms and particularly PMQR among Enterobacteriaceae as well as their methods of detection. Then the available data on the epidemiology of PMQR in clinical and environmental isolates from the Arab countries are extensively reviewed along with the other associated resistance genes. These data shows a wide dissemination of PMQR genes among Enterobacteriaceae isolates from humans, animals, and environments in these countries with increasing rates over the years and a common association with other antibiotic resistance genes as blaCTX-M-15. The incontrovertible emergence of PMQR in the Arab countries highlights the pressing need for effective stewardship efforts to prevent the selection of a higher rate of quinolone resistance and to preserve these crucial antibiotics.

Copyright © 2019. Published by Elsevier B.V.

KEYWORDS: Arab countries; Detection; Epidemiology; Molecular mechanisms; Plasmid-mediated quinolone resistance (PMQR); Quinolones

PMID: 31493557 DOI: 10.1016/j.meegid.2019.104020

Keywords: Antibiotics; Drugs Resistance; Quinolones; Enterobacteriaceae.


A #MDR #Plasmid pIMP26, Carrying blaIMP-26, fosA5, blaDHA-1, and qnrB4 in #Enterobacter cloacae (Sci Rep., abstract)

[Source: Scientific Reports, full page: (LINK). Abstract, edited.]

Article | OPEN | Published: 15 July 2019

A Multidrug Resistance Plasmid pIMP26, Carrying blaIMP-26, fosA5, blaDHA-1, and qnrB4 in Enterobacter cloacae

Su Wang,  Kaixin Zhou, Shuzhen Xiao, Lianyan Xie, Feifei Gu, Xinxin Li, Yuxing Ni, Jingyong Sun & Lizhong Han

Scientific Reports, volume 9, Article number: 10212 (2019)



IMP-26 was a rare IMP variant with more carbapenem-hydrolyzing activities, which was increasingly reported now in China. This study characterized a transferable multidrug resistance plasmid harboring blaIMP-26 from one Enterobacter cloacae bloodstream isolate in Shanghai and investigated the genetic environment of resistance genes. The isolate was subjected to antimicrobial susceptibility testing and multilocus sequence typing using broth microdilution method, Etest and PCR. The plasmid was analyzed through conjugation experiments, S1-nuclease pulsed-field gel electrophoresis and hybridization. Whole genome sequencing and sequence analysis was conducted for further investigation of the plasmid. E. cloacae RJ702, belonging to ST528 and carrying blaIMP-26, blaDHA-1, qnrB4 and fosA5, was resistant to almost all β-lactams, but susceptible to quinolones and tigecycline. The transconjugant inherited the multidrug resistance. The resistance genes were located on a 329,420-bp IncHI2 conjugative plasmid pIMP26 (ST1 subtype), which contained trhK/trhV, tra, parA and stbA family operon. The blaIMP-26 was arranged following intI1. The blaDHA-1 and qnrB4cluster was the downstream of ISCR1, same as that in p505108-MDR. The fosA5 cassette was mediated by IS4. This was the first report on complete nucleotide of a blaIMP-26-carrying plasmid in E. cloacae in China. Plasmid pIMP26 hosted high phylogenetic mosaicism, transferability and plasticity.

Keywords: Antibiotics; Drugs Resistance; Carbapenem; Beta-lactams; Enterobacter cloacae; Shanghai; China; Quinolones; Tigecycline.


Early #dissemination of qnrE1 in #Salmonella Typhimurium from #livestock in South #America (Antimicrob Agents Chemother., abstract)

[Source: Journal of Antimicrobial Chemotherapy, full page: (LINK). Abstract, edited.]

Early dissemination of qnrE1 in Salmonella Typhimurium from livestock in South America

Daniel F. Monte, Nilton Lincopan, Louise Cerdeira, Paula J. Fedorka-Cray, Mariza Landgraf

DOI: 10.1128/AAC.00571-19



The plasmid-mediated quinolone resistance (PMQR) gene qnrE1 has been limited to South America to date and was identified for the first time in Klebsiella pneumoniae from a human infection in Argentina in 2007 (1).…

Copyright © 2019 American Society for Microbiology. All Rights Reserved.

Keywords: Antibiotics; Drugs Resistance; Quinolones; South America; Cattle.


Co-Occurrence of #mcr-1 and qnrS1 on an IncHI2 #Plasmid in #Clinical Isolates of #SalmonellaTyphimurium in #Spain (Vector Borne Zoo Dis., abstract)

[Source: Vector Borne and Zoonotic Diseases, full page: (LINK). Abstract, edited.]

Co-Occurrence of mcr-1 and qnrS1 on an IncHI2 Plasmid in Clinical Isolates of SalmonellaTyphimurium in Spain

Teresa Trujillo-Soto, Jesús Machuca, Jorge Arca-Suárez, Manuel Rodríguez-Iglesias, and Fátima Galán-Sánchez

Published Online: 30 May 2019 / DOI: https://doi.org/10.1089/vbz.2018.2398



Salmonella enterica is a well-adapted zoonotic bacterium associated to cases of gastroenteritis and bacteremia with increased morbidity and mortality. In this study, three isolates of Salmonella Typhimurium obtained from human clinical samples, showing colistin resistance and low-level resistance to quinolones, have been genetically characterized. We detected the co-occurrence of mcr-1 and qnrS1 on a single IncHI2 plasmid in isolates of Salmonella Typhimurium obtained from Spanish children without a travel history. The multiresistant region contained numerous resistance genes. Isolates were clonally related, which suggests the presence of these clones in the community and the potential to cause outbreaks affecting the most susceptible population. It is necessary to monitor the presence of these plasmid-mediated resistance genes in human European strains of Salmonella spp. because of the risk of producing outbreaks of community-acquired infections.

Keywords: Antibiotics; Drugs Resistance; Colistin; Quinolones; Salmonella Typhimurium; Spain.