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Introduction Escherichia coli ST131 is the most common multidrug-resistant (MDR) E. coli clone causing bloodstream infections (BSIs) in Calgary. This study describes patient characteristics and spatial distribution of ST131 subclades C1 and C2 causing BSIs in Calgary. Methods E. coli from blood (n = 685) obtained in Calgary, Canada, (2016) were PCR screened for ST131 and positives (n = 141) underwent whole genome sequencing. Patient characteristics were analysed using Fisher’s Exact/t-tests and spatial analysis was used to identify clusters. Results Overall, 21% of E. coli was identified as ST131 and clade C dominated the population. ST131-C2 was associated with blaCTX-M-15 and significantly more MDR than ST131-C1. The spatial distribution in Calgary showed that ST131-C1 was mainly present in long-term care (LTC) residents whereas ST131-C2 clustered in a specific North East (NE) Calgary sector comprising of six neighbourhoods without LTC centres. This NE sector has high immigration and travel rates from the Indian subcontinent. Conclusions This study showed that ST131 C subclades have different geographical distribution patterns in Calgary. We believe that recent travel to and immigration from certain high-risk regions for antimicrobial resistance are responsible for the ST131-C2 NE Calgary clustering pattern.

Introduction Klebsiella pneumoniae with OXA-48-like enzymes were introduced into Tshwane Tertiary Hospital (TTH) (Pretoria, South Africa) during September 2015, causing nosocomial outbreaks. Methods PCR methodologies and WGS were used to characterize K. pneumoniae with carbapenemases (n = 124) from TTH (July 2015–December 2016). Results PCR was used to track K. pneumoniae ST307 with OXA-181 among 60% of carbapenemase-positive isolates in different wards/units over time and showed the transmission of IncX3 plasmids to other K. pneumoniae clones. WGS identified different ST307 clades: 307_OXA181 (consisting of two lineages, A and B) with OXA-181 on IncX3 plasmids (named p72_X3_OXA181) and clade 307_VIM with VIM-1 on IncFII plasmids. Clade 307_OXA181 lineage B was responsible for the rapid increase and transmission of OXA-181 K. pneumoniae in various wards/units throughout TTH, while the numbers of clade 307_OXA181 lineage A and clade 307_VIM remained low. Separate outbreaks were due to K. pneumoniae ST17 and ST29 with p72_X3_OXA181 plasmids. Conclusions The high-risk clone K. pneumoniae ST307 with OXA-181 rapidly spread to different wards/units despite infection and prevention measures. ST307 clades and lineages seemingly acted differently in outbreak situations. This study also highlighted the threat of promiscuous plasmids such as p72_X3_OXA181.

International data on the molecular epidemiology of Enterobacteriaceae with VIM carbapenemases are limited.We performed short read (Illumina) WGS on a global collection of 89 VIM-producing clinical Enterobacteriaceae (2008-14).VIM-producing (11 varieties within 21 different integrons) isolates were mostly obtained from Europe. Certain integrons with bla VIM were specific to a country in different species and clonal complexes (CCs) (In 87 , In 624 , In 916 and In 1323 ), while others had spread globally among various Enterobacteriaceae species (In 110 and In 1209 ). Klebsiella pneumoniae was the most common species ( n = 45); CC147 from Greece was the most prevalent clone and contained In 590 -like integrons with four different bla VIM s. Enterobacter cloacae complex was the second most common species and mainly consisted of Enterobacter hormaechei ( Enterobacter xiangfangensis , subsp. steigerwaltii and Hoffmann cluster III). CC200 (from Croatia and Turkey), CC114 (Croatia, Greece, Italy and the USA) and CC78 (from Greece, Italy and Spain) containing bla VIM-1 were the most common clones among the E. cloacae complex.This study highlights the importance of surveillance programmes using the latest molecular techniques in providing insight into the characteristics and global distribution of Enterobacteriaceae with bla VIM s.

OBJECTIVES To assess the proportion of Escherichia coli and Klebsiella pneumoniae from Canadian hospitals that produce extended-spectrum β-lactamases (ESBLs), AmpC β-lactamases and carbapenemases, as well as to describe the patterns of antibiotic resistance and molecular characteristics of these organisms. METHODS Some 5451 E. coli and 1659 K. pneumoniae were collected from 2007 to 2011 inclusive as part of the ongoing CANWARD national surveillance study. Antimicrobial susceptibility testing was performed to detect putative ESBL, AmpC and carbapenemase producers, which were then further characterized by PCR and sequencing to detect resistance genes. In addition, isolates were characterized by PFGE and an allele-specific PCR to detect isolates of sequence type (ST) 131. RESULTS The proportion of ESBL-producing E. coli (2007, 3.4%; 2011, 7.1%), AmpC-producing E. coli (2007, 0.7%; 2011, 2.9%) and ESBL-producing K. pneumoniae (2007, 1.5%; 2011, 4.0%) among the isolates collected increased during the study period. The majority of ESBL-producing E. coli (>95%), AmpC-producing E. coli (>97%) and ESBL-producing K. pneumoniae (>89%) remained susceptible to colistin, amikacin, ertapenem and meropenem. Isolates were generally unrelated by PFGE (

From international tourists to war-displaced refugees, more people are on the move than ever before. This provides the opportunity for a variety of antimicrobial-resistant bacteria to be carried from one geographic location to another. The Enterobacteriaceae are among the most important causes of serious hospital-acquired and community-onset bacterial infections in humans, and resistance to antimicrobial agents in these bacteria has become an increasingly relevant problem. International travel and tourism are important modes for the acquisition and spread of antimicrobial-resistant Enterobacteriaceae, especially CTX-M-producing Escherichia coli. Infections with KPC-, VIM-, OXA-48- and NDM-producing Enterobacteriaceae in developed countries have been associated with visiting and being hospitalized in endemic areas such as the USA, Greece and Israel for KPCs, Greece for VIMs, Turkey for OXA-48, and the Indian subcontinent for NDMs. To combat the spread of antimicrobial-resistant Enterobacteriaceae, the French Healthcare Safety Advisory Committee recently issued national recommendations for screening and contact isolation precautions for patients transferred from, or hospitalized outside, France. For effective public and patient health interventions, it is important to understand the role of international travel in the spread of antimicrobial-resistant Enterobacteriaceae. We urgently need well-designed studies to evaluate the transmission potential and risks for colonization and infections due to multiresistant Enterobacteriaceae in travellers who have recently visited or have been hospitalized in endemic areas. The emergence of CTX-M-, KPC- and NDM-producing bacteria is a good example of the role that globalization plays in the rapid dissemination of new antibiotic resistance mechanisms.

Objectives: A study was designed to investigate the molecular epidemiology of extended-spectrum β-lactamase (ESBL)-producing Klebsiella pneumoniae isolated in a centralized region over a 10 year period (2000-09). Methods: Molecular characterization was done using isoelectric focusing, PCR and sequencing for bla CTX-M, bla TEM and bla SHV genes and plasmid-mediated quinolone resistance determinants. Genetic relatedness was determined with PFGE using XbaI and multilocus sequencing typing. Results: A total of 89 patients with incident infections were identified; the majority presented with hospital-onset urinary tract infections. The absolute number of ESBL-producing isolates remained very low until 2003, increased slightly in 2004, remained stable until 2008 and then in 2009 there was an abrupt increase in the numbers of ESBL producers identified. The majority of K. pneumoniae produced CTX-M-14 and -15, and have replaced SHV-12-producing isolates since 2005. We identified four different major sequence types (STs) among 32% of isolates (i.e. ST17, ST20, and the new ST573 and ST575) and provided insight into their clinical and molecular characteristics. The ST isolates were more likely to produce community-onset infections, were associated with bla CTX-M and emerged during the latter part of the study period. ST17 produced CTX-M-15 and SHV-12, and was more likely to be positive for qnrB; ST20 produced CTX-M-14 and was positive for qnrS. The multiresistant ST575 that produced CTX-M-15 appeared in 2009. Conclusions: Our study highlights the importance of molecular epidemiology in providing insight into the emergence, characteristics and distribution of STs among ESBL-producing K. pneumoniae.

Background The global accumulation of Escherichia coli with CTX-M extended-spectrum s-lactamases partly reflects the dissemination of clonal lineages, notably ST131 and ST405. More recently, E. coli have emerged that produce NDM carbapenemase. We sought to determine the clonal diversity of E. coli with this enzyme from English hospitals, and to compare them with isolates from Pakistan and India. Methods The 18 NDM-positive E. coli were from hospitals in England (n?=?10), Pakistan (n?=?7) and India (n?=?1). Isolates were compared by phylogenetic grouping, multilocus sequence typing and PFGE of XbaI-digested DNA. Isolates were screened by PCR for acquired AmpC genes, blaCTX-M, and the 16S rRNA methylase genes armA and rmtC. Results Most of the isolates belonged to phylogenetic groups B1 (n?=?9) or D (n?=?7); two were group A and none was group B2. Nine isolates from England and Pakistan belonged to the B1 lineage ST101, with seven of these clustering at >77% similarity by PFGE. Other lineages included ST405 (n?=?3, group D), ST648 (n?=?3, group D), the ST23 complex (one each of ST90 and ST410, both group A) and ST156 (n?=?1, group D). Sixteen of 18 isolates had a group 1 CTX-M gene, 13 had a CIT-type acquired AmpC, and 16 had either or both of armA and rmtC. Conclusions The E. coli isolates producing NDM-1 carbapenemase belonged to six sequence types and included diverse clonal lineages. Nevertheless, isolates of B1-ST101 accounted for half the collection, and included isolates from both England and Pakistan. None of the isolates belonged to ST131 or to phylogroup B2.

Objectives A study was designed to determine the prevalence of plasmid-mediated quinolone resistance (PMQR) determinants among clinical isolates of Enterobacteriaceae from the Calgary Health Region (CHR). Methods During January and February 2004 and January and February 2007, 564 non-repeat isolates of Escherichia coli, Klebsiella spp., Proteus mirabilis and Morganella morganii resistant to ciprofloxacin and/or tobramycin were screened for PMQR determinants using a multiplex PCR for qnrA, qnrS and qnrB and aac(6')-Ib genes; aac(6')-Ib-cr was further identified by digestion with BstF5I. Results In 2004, 6/139 (4%) of the resistant E. coli were positive for aac(6')-Ib-cr. In 2007, 53/398 (13%) were positive for aac(6')-Ib-cr, 3/398 (0.8%) were positive for qnrS, and one isolate was positive for both. All the isolates were present in urines and the majority [40/63 (63%)] were submitted from community collection sites; 8 (13%) isolates co-produced AmpC beta-lactamases and 34 (54%) co-produced CTX-M-15. aac(6')-Ib-cr was present in one Klebsiella pneumoniae and one P. mirabilis, whereas one isolate of K. pneumoniae was positive for both aac(6')-Ib-cr and qnrB. Conclusions Our results showed that isolates with aac(6')-Ib-cr, often associated with CTX-M-15, are emerging among fluoroquinolone-resistant E. coli in the CHR. Our study suggests that surveillance for PMQR determinants should be undertaken on a regular basis.

Enterobacteriaceae, especially Klebsiella spp. producing extended-spectrum beta-lactamases (ESBLs) such as SHV and TEM types, have been established since the 1980s as a major cause of hospital-acquired infections. Appropriate infection control practices have largely prevented the dissemination of these bacteria within many hospitals, although outbreaks have been reported. However, during the late 1990s and 2000s, Enterobacteriaceae (mostly Escherichia coli) producing novel ESBLs, the CTX-M enzymes, have been identified predominantly from the community as a cause of urinary tract infections. Resistance to other classes of antibiotics, especially the fluoroquinolones, is often associated with ESBL-producing organisms. Many clinical laboratories are still not aware of the importance of screening for ESBL-producing Enterobacteriaceae originating from the community. A heightened awareness of these organisms by clinicians and enhanced testing by laboratories, including molecular surveillance studies, is required to reduce treatment failures, to limit their introduction into hospitals and to prevent the spread of these emerging pathogens within the community.

During a one year prospective study of Haemophilus influenzae infections in patients treated in hospitals in the metropolitan area of Cape Town. H. influenzae type b accounted for 81.7% of 126 invasive isolates, whereas 86.1% of the 280 non-invasive isolates were non-typeable. Ampicillin resistance was detected among 10.8% of strains of which all but one produced beta-lactamase. All strains were susceptible to cefotaxime as were more than 95% to chloramphenicol, rifampicin, tetracycline but 20.4% were resistant to co-trimoxazole and 87.2% to erythromycin.