RESUMO
Background: VRE are prevalent among patients in ICUs. Non-typeable vanA VRE, due to loss of one of the genes used for MLST (pstS), have increased in Australia, suggestive of a new, hospital-acquired lineage. Objectives: To understand the significance of this lineage and its transmission using WGS of strains isolated from patients in ICUs across New South Wales, Australia. Methods: A total of 240 Enterococcus faecium isolates collected between February and May 2016, and identified by conventional PCR as vanA positive, were sequenced. Isolates originated from 12 ICUs in New South Wales, grouped according to six local health districts, and represented both rectal screening swab (n = 229) and clinical (n = 11) isolates. Results: ST analysis revealed the absence of the pstS gene in 84.2% (202 of 240) of vanA isolates. Two different non-typeable STs were present based on different allelic backbone patterns. Loss of the pstS gene appeared to be the result of multiple recombination events across this region. Evidence for pstS-negative lineage spread across all six local health districts was observed suggestive of inter-hospital transmission. In addition, multiple outbreaks were detected, some of which were protracted and lasted for the duration of the study. Conclusions: These findings confirmed the evolution, emergence and dissemination of non-typeable vanA E. faecium. This study has highlighted the utility of WGS when attempting to describe accurately the hospital-based pathogen epidemiology, which in turn will continue to inform optimal infection control measures necessary to halt the spread of this important nosocomial organism.
Assuntos
Proteínas de Bactérias/genética , Infecção Hospitalar/transmissão , Enterococcus faecium/genética , Genoma Bacteriano , Infecções por Bactérias Gram-Positivas/epidemiologia , Enterococos Resistentes à Vancomicina/genética , Antibacterianos/uso terapêutico , Austrália/epidemiologia , Técnicas de Tipagem Bacteriana , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/microbiologia , Surtos de Doenças , Enterococcus faecium/classificação , Enterococcus faecium/efeitos dos fármacos , Infecções por Bactérias Gram-Positivas/transmissão , Humanos , Unidades de Terapia Intensiva/estatística & dados numéricos , New South Wales/epidemiologia , Reação em Cadeia da Polimerase , Vancomicina/farmacologia , Enterococos Resistentes à Vancomicina/isolamento & purificação , Sequenciamento Completo do GenomaRESUMO
We identified discrete importation events of the mcr-1 gene on incompatibility group IncI2 plasmids in Escherichia coli isolated from patients in New South Wales, Australia, in 2011 and 2013. mcr-1 is present in a small minority of colistin-resistant Enterobacteriaceae and appears not to be established locally.
Assuntos
Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/microbiologia , Proteínas de Escherichia coli/genética , Escherichia coli/genética , Antibacterianos/farmacologia , Austrália/epidemiologia , Sequência de Bases , Sítios de Ligação , Colistina/farmacologia , Farmacorresistência Bacteriana , Escherichia coli/efeitos dos fármacos , Escherichia coli/isolamento & purificação , Infecções por Escherichia coli/história , Microbiologia de Alimentos , História do Século XXI , Humanos , Testes de Sensibilidade Microbiana , Plasmídeos/genética , Regiões Promotoras Genéticas , Ribossomos/metabolismoRESUMO
The BD Max StaphSR assay is an automated qualitative in vitro diagnostic test for the direct detection and differentiation of methicillin-susceptible Staphylococcus aureus (MSSA) and methicillin-resistant S. aureus (MRSA). A total of 460 specimens were tested, and the results were compared with standard culture-based identification. MRSA was detected in 48 samples (sensitivity of 100%; positive predictive value [PPV] of 100%). MSSA was detected in 112 samples (sensitivity of 99.1%; PPV of 100%), and 299 samples containing coagulase-negative staphylococcus and nonstaphylococcal species were negative by the BD Max StaphSR assay (specificity of 100%; negative predictive value [NPV] of 99.7 to 100%).
Assuntos
Bacteriemia/diagnóstico , Técnicas Bacteriológicas/métodos , Testes Diagnósticos de Rotina/métodos , Infecções Estafilocócicas/diagnóstico , Staphylococcus aureus/isolamento & purificação , Automação Laboratorial/métodos , Humanos , Sensibilidade e Especificidade , Fatores de TempoRESUMO
pJIE143 (34 kb), from an Escherichia coli ST131 isolate, carries bla(CTX-M-15) but could not be typed using the standard PCR-based replicon-typing primer set. Complete sequencing revealed a backbone with similarity to IncX plasmids, including a pir-like gene encoding a π-like replication protein and iterons related to those of other IncX plasmids. The 2.971-kb ISEcp1-bla(CTX-M-15)-orf477Δ transposition unit often found within Tn2 is inserted just beyond the end of pir, flanked by 5-bp direct repeats.
Assuntos
Escherichia coli/isolamento & purificação , Plasmídeos/genética , Análise de Sequência de DNA , beta-Lactamases/genética , Sequência de Bases , Elementos de DNA Transponíveis/genética , Escherichia coli/enzimologia , Escherichia coli/genética , Infecções por Escherichia coli/microbiologia , Proteínas de Escherichia coli/genética , Humanos , Testes de Sensibilidade Microbiana , Dados de Sequência Molecular , Reação em Cadeia da PolimeraseRESUMO
Despite the reported elimination of measles virus in Australia, importation of cases from endemic countries continues to lead to secondary local transmission and outbreaks. Rapid laboratory confirmation of measles is paramount for individual patient management and outbreak responses. Further, it is important to rapidly distinguish infection from wild-type virus or vaccine strains to guide public health responses. We developed a high throughput, TaqMan-based multiplex reverse-transcription-polymerase chain reaction (PCR) assay using the BD MAX platform (Becton Dickinson) that simultaneously detects measles virus and differentiates between wild-type and vaccine strains without the need for sequencing.