Long-term-care facilities (LTCFs) are reservoirs of resistant bacteria. We undertook a point-prevalence survey and risk factor analysis for specific resistance types among residents and staff of a ...Bolzano LTCF and among geriatric unit patients in the associated acute-care hospital. Urine samples and rectal, inguinal, oropharyngeal and nasal swabs were plated on chromogenic agar; isolates were typed by pulsed-field gel electrophoresis; resistance genes and links to insertion sequences were sought by PCR; plasmids were analysed by PCR, restriction fragment length polymorphism and incompatibility grouping. Demographic data were collected. Of the LTCF residents, 74.8% were colonized with ≥1 resistant organism, 64% with extended-spectrum β-lactamase (ESBL) producers, 38.7% with methicillin-resistant Staphylococcus aureus (MRSA), 6.3% with metallo-β-lactamase (MBL) producers, and 2.7% with vancomycin-resistant enterococci. Corresponding rates for LTCF staff were 27.5%, 14.5%, 14.5%, 1.5% and 0%, respectively. Colonization frequencies for geriatric unit patients were lower than for those in the LTCF. Both clonal spread and plasmid transfer were implicated in the dissemination of MBL producers that harboured IncN plasmids bearing blaVIM-1, qnrS, and blaSHV-12. Most (44/45) ESBL-producing Escherichia coli isolates had blaCTX-M genes of group 1; a few had blaCTX-M genes of group 9 or blaSHV-5; those with blaCTX-M-15 or blaSHV-5 were clonal. Risk factors for colonization of LTCF residents with resistant bacteria included age ≥86 years, antibiotic treatment in the previous 3 months, indwelling devices, chronic obstructive pulmonary disease, physical disability, and the particular LTCF unit; those for geriatric unit patients were age and dementia. In conclusion, ESBL-producing and MBL-producing Enterobacteriaceae and MRSA were prevalent among the LTCF residents and staff, but less so in the hospital geriatric unit. Education of LTCF employees and better infection control are proposed to minimize the spread of resistant bacteria in the facility.
Abstract
Background
Previous studies showed that the epidemic of carbapenem-resistant Klebsiella pneumoniae (CR-KP) observed in Italy since 2010 was sustained mostly by strains of clonal group (CG) ...258 producing KPC-type carbapenemases. In the framework of the National Antibiotic-Resistance Surveillance (AR-ISS), a countrywide survey was conducted in 2016 to explore the evolution of the phenotypic and genotypic characteristics of CR-KP isolates.
Methods
From March to July 2016, hospital laboratories participating in AR-ISS were requested to provide consecutive, non-duplicated CR-KP (meropenem and/or imipenem MIC >1 mg/L) from invasive infections. Antibiotic susceptibility was determined according to EUCAST recommendations. A WGS approach was adopted to characterize the isolates by investigating phylogeny, resistome and virulome.
Results
Twenty-four laboratories provided 157 CR-KP isolates, of which 156 were confirmed as K. pneumoniae sensu stricto by WGS and found to carry at least one carbapenemase-encoding gene, corresponding in most cases (96.1%) to blaKPC. MLST- and SNP-based phylogeny revealed that 87.8% of the isolates clustered in four major lineages: CG258 (47.4%), with ST512 as the most common clone, CG307 (19.9%), ST101 (15.4%) and ST395 (5.1%). A close association was identified between lineages and antibiotic resistance phenotypes and genotypes, virulence traits and capsular types. Colistin resistance, mainly associated with mgrB mutations, was common in all major lineages except ST395.
Conclusions
This WGS-based survey showed that, although CG258 remained the most common CR-KP lineage in Italy, a polyclonal population has emerged with the spread of the new high-risk lineages CG307, ST101 and ST395, while KPC remained the most common carbapenemase.
The emergence of metallo-β-lactamase (MBL)-producing Enterobacteriaceae is a serious public health concern. Producers have been repeatedly isolated from patients and long-term care facility (LTCF) ...residents around Bolzano, and we sought to assess their prevalence and clinical impact. All routine Enterobacteriaceae isolates from a Bolzano tertiary-care hospital and associated long-term care facilities in 2008 (n = 5500) were screened for MBLs, with case details reviewed for the source patients. In total, 36 producers were obtained from 29 patients, comprising 14 Escherichia coli, six Klebsiella pneumoniae, four Klebsiella oxytoca, four Citrobacter freundii, two Enterobacter cloacae and two Morganella morganii, as well as single Citrobacter amalonaticus, Enterobacter aerogenes, Providencia stuartii and Proteus mirabilis isolates. All were PCR-positive for blaVIM and 25 were PCR-positive for qnrS; 19 non-K. pneumoniae had blaSHV and one had blaCTX-M-group1; 13 were from 12 LTCF residents and 23 were from 17 acute-care patients. All these patients had serious underlying diseases with prolonged hospitalization or LTCF stay; only seven had infections due to the MBL producers, comprising four urinary tract infections, two catheter-related bloodstream infections and one patient with both a surgical site infection and pneumonia. Five patients had more than one MBL-producing organism. Pulsed-field gel electrophoresis identified a cluster of six related E. coli, whereas pairs of K. pneumoniae and C. freundii isolates had >85% profile similarity. Transformants prepared from two isolates were shown to be PCR-positive for blaVIM, qnrS and blaSHV; their plasmids gave similar restriction fragment length polymorphism patterns, and blaVIM-1, qnrSI and blaSHV-12 were detected by sequencing.
This study explores middle school students' aspirations in science, technology, engineering, and medical (STE-M) careers by analyzing survey data during their eighth and ninth grade years from an ...ethnically and economically diverse sample of Southern California urban and suburban public school students (n = 493). Students were classified based on their responses to questions about their science ability beliefs and subjective task values using latent class analysis (LCA). Four distinct groups of students were identified: Science is Me; I Value Science But Don't Do It Well; I Can Do Science but I Don't Value It Highly; and Science is Not Me. Few students (22 %) were classified as having strong science ability beliefs, and only a third as strongly valuing learning/doing science; a majority (57 %) were in the Science is Not Me category, underscoring the scope of the challenge to invite more young people to want to learn science. As predicted, students who believed they could do science and valued science were more likely than others to indicate interest in STE-M careers. This relationship between perceptions and aspirations was true regardless of gender, ethnicity, and type of STE-M field, but varied depending on socioeconomic status. Using LCA to organize information about students' science self-perceptions may help target specific interventions to student interests and aspirations and better support and encourage their persistence in STE-M careers.
Objectives We determined the complete nucleotide sequence of pKOX105, a 54 641 bp plasmid from a Klebsiella oxytoca strain that was isolated from a resident of a long-term-care facility in Bolzano, ...Italy. Methods The plasmid was sequenced using a shotgun approach. Combinatorial PCRs, directed PCRs and walking reads were used to assemble the contigs and to fill in gaps. Gene sequences were compared with reference plasmids and aligned with GenBank data using BLAST and CLUSTAL W software. Results pKOX105 belonged to incompatibility group IncN, harboured blaVIM-1, blaSHV-12, qnrS1, aacA4 and dfrA14 and conferred resistance to carbapenems, oxyimino-cephalosporins, quinolones, aminoglycosides and trimethoprim. It was highly related to the p9 and p12 plasmids from Klebsiella pneumoniae and K. oxytoca strains isolated at a New York City hospital in 2005 carrying blaKPC-2 and blaKPC-3, respectively. Conclusions IncN plasmids are broad host-range plasmids that have contributed significantly to the worldwide dissemination of many different resistance genes in Enterobacteriaceae from animal and human sources. This plasmid family is now playing a crucial role in the global spread of diverse carbapenemase genes in Klebsiella spp.
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