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Huiqiong Liu,1 Dao Wang,1 Miaomiao Tang,1 Peisheng Jia,1 Yufeng Huo,1 Erhu Wei,1 Hao Xu,2 Xiaohui Chi,2 Huaili Wang1 1Department of Pediatric Intensive Care Unit, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, 450052, People’s Republic of China; 2Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, the First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, People’s Republic of ChinaCorrespondence: Huaili Wang, Department of Pediatric Intensive Care Unit, The First Affiliated Hospital of Zhengzhou University, No. 1 Longhu East Zhonghuan Road, Zhengzhou, 450052, People’s Republic of China, Tel +86-371-66271057, Email whlek6527@126.comPurpose: With the spread of multiple drug-resistant bacteria, blaNDM-1 and mcr-9 have been detected in various bacteria worldwide. However, the simultaneous detection of blaNDM-1 and mcr-9 in Enterobacter hormaechei has been rarely reported. This study identified an E. hormaechei strain carrying both blaNDM-1 and mcr-9. We investigated the genetic characteristics of these two resistance genes in detail, elucidating various potential mechanisms by which they may be transmitted.Methods: Bacterial genomic features and possible origins were assessed by whole-genome sequencing (WGS) with Illumina and PacBio platforms and phylogenetic analysis. Subsequent investigations were performed, including antimicrobial susceptibility testing and multilocus sequence typing (MLST).Results: We isolated an E. hormaechei strain DY1901 carrying both blaNDM-1 and mcr-9 from the sputum sample. Susceptibility testing showed that the isolate was multidrug-resistant. Multiple antibiotic resistance genes and virulence genes are widely distributed in DY1901. S1-PFGE, Southern blotting, and plasmid replicon typing showed that DY1901 carried four plasmids. The plasmid carrying mcr-9 was 259Kb in size and belonged to In

Shuguang Xu,1 Jinjing Tu,1 Liang Zhang,1 Yinv Chen,1 Xiaoqi Dong,1 Xiaohui Chi,2,* Hao Xu2,* 1Department of Pulmonary and Critical Care Medicine, Ningbo Medical Center Lihuili Hospital, Ningbo, People’s Republic of China; 2Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, People’s Republic of China*These authors contributed equally to this workCorrespondence: Hao Xu; Xiaohui Chi, Email xuhao930523@163.com; chixiaohui@zju.edu.cnPurpose: Nosocomial infections caused by New Delhi metallo-β-lactamase (NDM)-producing bacteria are prevalent worldwide. However, such diseases caused by NDM-producing Aeromonas caviae had never been reported. Our study aimed to elucidate the genomic characteristics of NDM-1-producing A. caviae isolated from hospital patients.Methods: Bacterial genomic features and possible origins were assessed by whole-genome sequencing (WGS) and phylogenetic analysis. Subsequent investigations include antimicrobial susceptibility testing and multilocus sequence typing (MLST).Results: We identified here two NDM-1-producing A. caviae isolates from bacteremia. Susceptibility testing showed that two isolates were multi-drug resistant and shared a similar resistance profile and were only sensitive to amikacin and trimethoprim/sulfamethoxazole. Both A. caviae isolates carry the carbapenem resistance gene blaNDM-1 and also have antibiotic resistance genes such as β-lactams, AmpC enzymes, macrolides, aminoglycosides, and quinolones. S1-PFGE and Southern blot analysis were negative. Whole-genome sequencing and comparative analysis revealed that these two isolates shared a close relationship.Conclusion: To the best of our knowledge, this work describes the first detection of non-plasmid encoded blaNDM-1 in A. caviae. The A. caviae isolated in this stu

Ganfeng Liang,1,* Yuting Rao,2,3,* Shuang Wang,4 Xiaohui Chi,2 Hao Xu,2 Yang Shen1 1Department of Infectious Diseases, The First Hospital of Taizhou, Taizhou, People’s Republic of China; 2Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, People’s Republic of China; 3Department of Laboratory Medicine, Puyang Oil Field General Hospital, Puyang, People’s Republic of China; 4Institute of Bacterial Infection Disease Control, Shandong Centre for Disease Control and Prevention, Jinan, People’s Republic of China*These authors contributed equally to this workCorrespondence: Yang Shen; Hao Xu Email Shenyanghtt@163.com; xuhao0523@zju.edu.cnBackground: The emergence of the plasmid-borne colistin-resistant gene (mcr-1) poses a great threat to human health. What is worse, the recent observations of the coexistence of mcr-1 with carbapenemase encoding genes in some bacteria caused even more concern. Yet, there is a lack of observations of such strains in the human gut.Methods: The isolation of E. coli L889 was performed on selective medium plates. Antibiotic susceptibilities were determined by an agar dilution and a broth microdilution method. Multi-locus sequence typing (MLST) and acquired resistance genes were also characterized. Transferability of blaNDM-9/mcr-1-carrying plasmids was determined by conjugation, replicon typing and S1-Pulsed-field gel electrophoresis (S1-PFGE), and Southern blotting. The sequences of these plasmids were analyzed by using whole-genome sequencing with Illumina Novaseq and Nanopore platforms.Results: E. coli L889 was identified as ST1101 concomitantly carrying blaNDM-9 and mcr-1 from a stool sample. Antimicrobial susceptibility tests showed that it was resistant to various antimicrobial agents and only susceptible to tigecycline. N

Weijie Cao,1,* Lina Guan,1,* Xiaoning Li,1 Ran Zhang,1 Li Li,1 Suping Zhang,1 Chong Wang,1 Xinsheng Xie,1 Zhongxing Jiang,1 Dingming Wan,1 Xiaohui Chi2 1Department of Hematology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, People’s Republic of China; 2Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, People’s Republic of China*These authors contributed equally to this workCorrespondence: Weijie Cao Email caoweijie2003@126.comPurpose: To explore the epidemiological characteristics and risk factors of bloodstream infections (BSI) in patients who develop agranulocytosis fever after allogeneic hematopoietic stem cell transplantation (allo-HSCT). This study also provides a basis for the clinical treatment of BSI.Methods: A retrospective analysis of 397 allo-HSCT patients in the Department of Hematology of our hospital was conducted from January 2013 to December 2017 to analyze the incidence of BSI, the distribution and types of pathogenic bacteria, and drug resistance rates. We also determined whether various parameters are risk factors to BSI, including the patient age, gender, disease type, transplantation method, stem cell source, pre-treatment with anti-thymocyte globulin (ATG), and agranulocytosis time.Results: Among the 397 allo-HSCT patients, 294 had a fever during the period of agranulocytosis, and 52 cases were found to have BSI. The incidence of BSI in patients with agranulocytosis fever was 17.7% (52/294). Among the 60 pathogens detected, 43 (71.67%), 10 (16.67%), and 7 (11.67%) were Gram negative strains, Gram positive strains, and fungi, respectively. The most common bacteria were Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa. The detection rate of extended-spectrum β-lactamase (ESBL) was 40.0%, and

Infections caused by carbapenem-resistant Enterobacteriaceae are a growing concern worldwide. Raoultella ornithinolytica is a species in the Enterobacteriaceae family which can cause hospital-acquired infections and is sporadically reported as carbapenem-resistant from human and environmental sources. In this study, we firstly report on an NDM-1-producing R. ornithinolytica, Rao166, isolated from drinking water in an animal cultivation area in China. In addition to carbapenem-resistance, Rao166 was resistant to several other antibiotics including gentamicin, sulfamethoxazole-trimethoprim, tetracycline and fosfomycin. Rao166 carried a novel IncFIC-type megaplasmid, 382,325 bp in length (pRAO166a). A multidrug resistance region, 60,600 bp in length, was identified in the plasmid containing an aac(3)-IId-like gene, aac(6)-Ib-cr, bla(DHA-1),bla(TEM-1B), bla(OXA-M-3), bla(NDM-1), qnrB4, catB3, arr-3, sul1, and tet(D). Results from virulence assays implied that Rao166 has considerable pathogenic potential. Although pRAO166a was found to be non-transmissible, dissemination of the NDM-1 producing strain may occur from well water to humans or animals through cross-contamination during food preparation or directly via drinking water, and potentially lead to difficult-to-treat infections. Thus, contamination of well water by this carbapenem-resistant and presumptively virulent strain of R. ornithinolytica should be considered a potential public health risk. (C) 2020 Elsevier Ltd. All rights reserved., Funding Agencies|National Natural Science Foundation of ChinaNational Natural Science Foundation of China [41771499, 81741098]; Fundamental Research Funds of Shandong University [2018JC102]; Swedish Research Council FormasSwedish Research CouncilSwedish Research Council Formas [2016-00640]; Swedish Foundation for International Cooperation in Research and Higher Education (STINT) [CH2016-6707]

It is becoming increasingly recognized that the environment plays an important role both in the emergence and in dissemination of antibiotic-resistant bacteria (ARB), Mechanisms and factors facilitating this development are, however, not yet well understood. The high detection rate of CTX-M genes in environmental sources provides an opportunity to explore this issue. In this study, 88 CTX-M-producing Escherichia coli were isolated from 30 pig feces samples from 30 pig farms and 201 environmental samples. CTX-M-producing E. coli was detected with the following frequencies in the different types of samples: pig feces, 73%; river water, 64%; river sediment, 52%; wastewater, 31%; drinking water, 23%; outlet sediment, 21%; soil, 17%; and vegetables, 4.4%. Dissemination of CTX-M-producing E. coli to different environmental matrices was evaluated by analyzing the genetic relatedness of isolates from different environmental sources, and putative transmission routes through bird feces, pig feces, drinking water, river sediment, river water, and wastewater were hypothesized. Dissemination through these routes is likely facilitated by anthropogenic activities and environmental factors. Wild birds as potential vectors for dissemination of CTX-M-producing E. coli have the capacity to spread ARB across long distances. Regional dissemination between different environmental matrices of CTX-M-producing E. coli increases the exposure risk of humans and animals in the area., Funding Agencies|National Natural Science Foundation of China [41771499, 81361138021]; Fundamental Research Funds of Shandong University [2018JC102]; Swedish Research Council; Public Health Agency of Sweden [D0879801]; Swedish Research Council Formas [2016-00640]

Xiaohui Chi,1,2,* Guangchun Hu,3,* Hao Xu,2 Xiucun Li,4 Tingting Xiao,2 Yanzi Zhou,2 Huiyu Xia,1 Huiyun Zou,1 Hui Han,4 Beiwen Zheng,2 Haiyan Gao,4 Xuewen Li1 1Department of Environment and Health, School of Public Health, Shandong University, Jinan 250012, People’s Republic of China; 2Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, State Key Laboratory for Diagnosis and Treatment of Infectious Disease, the First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, People’s Republic of China; 3Division of Bacteria Diseases, Jinan Municipal Center for Disease Control and Prevention, Jinan, People’s Republic of China; 4Department of Infection Control, Qilu Hospital of Shandong University, Jinan 250012, People’s Republic of China*These authors contributed equally to this workCorrespondence: Xuewen LiDepartment of Environment and Health, School of Public Health, Shandong University, Jinan 250012, People’s Republic of ChinaEmail lxw@sdu.edu.cnHaiyan GaoDepartment of Infection Control, Qilu Hospital of Shandong University, 107 Wenhua West Road, Jinan 250012, People’s Republic of ChinaEmail 565272040@qq.comPurpose: Klebsiella pneumoniae carbapenemase (KPC)-producing K. pneumoniae bacteria causes nosocomial infections worldwide. However, KPC-producing K. pneumoniae outbreak has never been reported in Shandong Province, China. The purpose of our study was to elucidate the epidemiological and drug resistance mechanisms of KPC-producing K. pneumoniae strains collected from a large teaching hospital in Shandong during the outbreak. Moreover, we attempted to characterize the genetic environment and phylogenetic analysis of blaKPC-2 in outbreak isolates.Methods: We monitored a 64-day outbreak of infection in a general hospital in Shandong Province, and the bacteria causing the infection were all ST11-type K. pneumoniae. The genotype correlation of KPC-producing K. p

Antibiotic resistance among gram-negative bacteria is increasingly becoming a problem of global concern. Particularly problematic is the emergence of resistance to last-resort antibiotics such as carbapenems and colistin. The increasing number of reports on the plasmid-mediated colistin resistance gene mcr-1 in isolates worldwide is raising concerns for the future usefulness of this class of antibiotics. Dissemination of mcr-1 is believed to have originated mainly from animal breeding, however, the role of the environment as a transmission source is not yet fully understood. In the current study, 89 extended spectrum beta-lactamase-producing Escherichia coli isolated from 231 samples from different environmental sources in 12 villages in a rural area of Shandong, China, were screened for mcr-1.17 (19.1%) mcr-1-positive isolates were found from different environmental sources, aggregated in 6 villages. Plasmids of three different Inc-groups carrying mcr-1 were confirmed, indicating that the widespread geographical distribution of mcr-1 in the local area is due to a number of different plasmids. Additionally, almost a third (29.4%) of the isolates carried virulence factors associated to intestinal pathogenic E. coli. These results illustrate the high complexity of the transmission patterns of mcr-1 among different environmental matrices on a local scale and the potential for the environment to facilitate dissemination and emergence of antibiotic-resistant and virulent strains of bacteria. (C) 2019 Elsevier Ltd. All rights reserved., Funding Agencies|National Natural Science Foundation of China [41771499, 81361138021]; Fundamental Research Funds of Shandong University [2018JC102]; Swedish Research Council; Public Health Agency of Sweden [D0879801]; Swedish Research Council Formas [2016-00640]