scholarly journals Emergence and Spread of Different ESBL-Producing Salmonella enterica Serovars in Hospitalized Horses Sharing a Highly Transferable IncM2 CTX-M-3-Encoding Plasmid

2020 ◽  
Vol 11 ◽  
Author(s):  
Ziv Dor ◽  
Anat Shnaiderman-Torban ◽  
Kira Kondratyeva ◽  
Maya Davidovich-Cohen ◽  
Assaf Rokney ◽  
...  
Keyword(s):  
Host Range ◽  
Salmonella Enterica ◽  
Meta Analysis ◽  
Health Hazard ◽  
Companion Animals ◽  
Antibiotic Resistance Genes ◽  
Complete Sequence ◽  
Control Measures ◽  
Health Concern ◽  
Broad Host Range

Salmonella enterica is a major causative pathogen of human and animal gastroenteritis. Antibiotic resistant strains have emerged due to the production of extended-spectrum β-lactamases (ESBLs) posing a major health concern. With the increasing reports on ESBL-producing Enterobacterales that colonize companion animals, we aimed to investigate ESBL dissemination among ESBL-producing Salmonella enterica (ESBL-S) in hospitalized horses. We prospectively collected ESBL-S isolates from hospitalized horses in a Veterinary-Teaching Hospital during Dec 2015–Dec 2017. Selection criteria for ESBL-S were white colonies on CHROMagarESBL plates and an ESBL phenotypic confirmation. Salmonella enterica serovars were determined using the Kaufmann-White-Le-Minor serological scheme. ESBL-encoding plasmids were purified, transformed and compared using restriction fragment length polymorphism (RFLP). Whole genome sequencing (Illumina and MinION platforms) were performed for detailed phylogenetic and plasmid analyses. Twelve ESBL-S were included in this study. Molecular investigation and Sequence Read Archive (SRA) meta-analysis revealed the presence of three unique Salmonella enterica serovars, Cerro, Havana and Liverpool, all reported for the first time in horses. PFGE revealed the clonal spread of S. Cerro between seven horses. All twelve isolates carried blaCTX–M–3 and showed an identical multidrug resistance profile with co-resistance to trimethoprim/sulfamethoxazole and to aminoglycosides. Plasmid RFLP proved the inter-serovar horizontal spread of a single blaCTX–M–3-encoding plasmid. Complete sequence of a representative plasmid (S. Havana strain 373.3.1), designated pSEIL-3 was a -86.4 Kb IncM2 plasmid, that encoded nine antibiotic resistance genes. pSEIL-3 was virtually identical to pCTX-M3 from Citrobacter freundii, and showed high identity (>95%) to six other blaCTX–M–3 or blaNDM–1 IncM2 broad host range plasmids from various Enterobacterales of human origin. Using a specific six gene-based multiplex PCR, we detected pSEIL-3 in various Enterobacterales species that co-colonized the horses’ gut. Together, our findings show the alarming emergence of ESBL-S in hospitalized horses associated with gut shedding and foal morbidity and mortality. We demonstrated the dissemination of CTX-M-3 ESBL among different Salmonella enterica serovars due to transmission of a broad host range plasmid. This report highlights horses as a zoonotic reservoir for ESBL-S, including highly transmissible plasmids that may represent a ‘One-Health’ hazard. This risk calls for the implementation of infection control measures to monitor and control the spread of ESBL-S in hospitalized horses.

scholarly journals Diversity and Host Specificity Revealed by Biological Characterization and Whole Genome Sequencing of Bacteriophages Infecting Salmonella enterica

Viruses ◽  
2019 ◽  
Vol 11 (9) ◽  
pp. 854 ◽  
Author(s):  
Fong ◽  
Tremblay ◽  
Delaquis ◽  
Goodridge ◽  
Levesque ◽  
...  
Keyword(s):  
Host Range ◽  
Salmonella Enterica ◽  
Nucleotide Identity ◽  
Comparative Genomic ◽  
Broad Host Range ◽  
Natural Environments ◽  
Host Interactions ◽  
Knowledge Framework ◽  
Isolation And Characterization ◽  
Opportunistic Human Pathogen

Phages infecting members of the opportunistic human pathogen, Salmonella enterica, are widespread in natural environments and offer a potential source of agents that could be used for controlling populations of this bacterium; yet, relatively little is known about these phages. Here we describe the isolation and characterization of 45 phages of Salmonella enterica from disparate geographic locations within British Columbia, Canada. Host-range profiling revealed host-specific patterns of susceptibility and resistance, with several phages identified that have a broad-host range (i.e., able to lyse >40% of bacterial hosts tested). One phage in particular, SE13, is able to lyse 51 out of the 61 Salmonella strains tested. Comparative genomic analyses also revealed an abundance of sequence diversity in the sequenced phages. Alignment of the genomes grouped the phages into 12 clusters with three singletons. Phages within certain clusters exhibited extraordinarily high genome homology (>98% nucleotide identity), yet between clusters, genomes exhibited a span of diversity (<50% nucleotide identity). Alignment of the major capsid protein also supported the clustering pattern observed with alignment of the whole genomes. We further observed associations between genomic relatedness and the site of isolation, as well as genetic elements related to DNA metabolism and host virulence. Our data support the knowledge framework for phage diversity and phage–host interactions that are required for developing phage-based applications for various sectors, including biocontrol, detection and typing.

scholarly journals The Prevalence of Malaria among Pregnant Women in Ethiopia: A Systematic Review and Meta-Analysis

2019 ◽  
Vol 2019 ◽  
pp. 1-9 ◽  
Author(s):  
Yalewayker Tegegne ◽  
Daniel Asmelash ◽  
Sintayehu Ambachew ◽  
Setegn Eshetie ◽  
Ayenew Addisu ◽  
...  
Keyword(s):  
Systematic Review ◽  
Pregnant Women ◽  
Prevention And Control ◽  
Meta Analysis ◽  
Control Measures ◽  
Health Concern ◽  
Premature Delivery ◽  
Pooled Prevalence ◽  
Prevention And Control Measures ◽  
And Control

Background. Malaria during pregnancy remains a major public health concern in tropical and subtropical countries. Moreover, malaria is increasingly associated with unwanted pregnancy outcomes such as an increased risk of abortion, stillbirth, premature delivery, and low-birthweight infants. Since pregnant women are most vulnerable to malaria, implementation of the appropriate prevention and control measures among this group is very important. Therefore, the current review was designed to assess the prevalence of both symptomatic and asymptomatic malaria among pregnant women in Ethiopia.Method. In this systematic review and meta-analysis we have followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guideline. The databases used were PubMed, Google Scholar, HINARI, and Science Direct literature. Search terms used were “prevalence”, “malaria”, “pregnant women”, and “Ethiopia”. Joanna Briggs Institute Meta-Analysis of Statistics Assessment and Review Instrument (JBI-MAStARI) was used for critical appraisal of studies. The meta-analysis was conducted using STATA 14 software. The pooled meta-logistic regression was computed to present the pooled prevalence with a 95% confidence interval (CI).Result. Among a total of 10207 studies, seven studies were included in this analysis. The estimated pooled prevalence of malaria among pregnant women in Ethiopia was 12.72% (95% CI: 7.45, 17.98). In subgroup analysis, the prevalence of malaria showed a significant variation between asymptomatic and symptomatic cases, which was 7.83% (95% CI: 2.23, 13.43) and 17.97% (95% CI: 7.31, 28.92), respectively.Conclusion. The current systematic review and meta-analysis showed that the pooled prevalence of malaria among pregnant women was found to be relatively higher compared with the general population. Therefore, the existing prevention and control measures should be strengthen.

scholarly journals JD419, a Staphylococcus aureus Phage With a Unique Morphology and Broad Host Range

2021 ◽  
Vol 12 ◽  
Author(s):  
Tingting Feng ◽  
Sebastian Leptihn ◽  
Ke Dong ◽  
Belinda Loh ◽  
Yan Zhang ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Host Range ◽  
Antibiotic Resistance Genes ◽  
Multidrug Resistant ◽  
Complete Characterization ◽  
Resistant Bacteria ◽  
Broad Host Range ◽  
Gene Engineering ◽  
Mrsa Strains

Phage therapy represents a possible treatment option to cure infections caused by multidrug-resistant bacteria, including methicillin and vancomycin-resistant Staphylococcus aureus, to which most antibiotics have become ineffective. In the present study, we report the isolation and complete characterization of a novel phage named JD219 exhibiting a broad host range able to infect 61 of 138 clinical strains of S. aureus tested, which included MRSA strains as well. The phage JD419 exhibits a unique morphology with an elongated capsid and a flexible tail. To evaluate the potential of JD419 to be used as a therapeutic phage, we tested the ability of the phage particles to remain infectious after treatment exceeding physiological pH or temperature. The activity was retained at pH values of 6.0–8.0 and below 50°C. As phages can contain virulence genes, JD419’s complete genome was sequenced. The 45509 bp genome is predicted to contain 65 ORFs, none of which show homology to any known virulence or antibiotic resistance genes. Genome analysis indicates that JD419 is a temperate phage, despite observing rapid replication and lysis of host strains. Following the recent advances in synthetic biology, JD419 can be modified by gene engineering to remove prophage-related genes, preventing potential lysogeny, in order to be deployed as a therapeutic phage.

scholarly journals Evolution of Salmonella enterica serotype Typhimurium driven by anthropogenic selection and niche adaptation

2019 ◽  
Author(s):  
Matt Bawn ◽  
Gaetan Thilliez ◽  
Mark Kirkwood ◽  
Nicole Wheeler ◽  
Liljana Petrovska ◽  
...  
Keyword(s):  
Host Range ◽  
Salmonella Enterica ◽  
Genotypic Variation ◽  
Avian Species ◽  
Whole Genome Sequence ◽  
Broad Host Range ◽  
Niche Adaptation ◽  
Disseminated Disease ◽  
Distinct Distribution ◽  
Anthropogenic Selection

AbstractSalmonella enterica serotype Typhimurium (S. Typhimurium) is a leading cause of gastroenteritis and disseminated disease worldwide. Two S. Typhimurium strains (SL1344 and ATCC14028) are widely used to study host-pathogen interactions, yet genotypic variation results in strains with diverse host range, pathogenicity and risk to food safety. A robust fully parsimonious phylogenetic tree constructed from recombination purged variation in the whole genome sequence of 131 diverse strains of S. Typhimurium revealed population structure composed of two high order clades (α and β) and multiple subclades on extended internal branches, that exhibited distinct signatures of host adaptation and anthropogenic selection. Clade α contained a number of subclades composed of strains from well characterized epidemics in domesticated animals, while clade β predominantly contained subclades associated with wild avian species, with the notable exception of a subclade containing the DT204/49 complex. The contrasting epidemiology of α and β strains was reflected in a distinct distribution of antimicrobial resistance (AMR) genes, accumulation of hypothetically disrupted coding sequences (HDCS), and signatures of functional diversification associated with invasiveness of host adapted serotypes. Gene flux was predominantly driven by acquisition, loss or recombination of prophage. The acquisition of large genetic islands (SGI-1 and 4) was limited to two recent pandemic clones (DT104 and monophasic S. Typhimurium ST34) in clade α. Together, our data are consistent with the view that a broad host range common ancestor of S. Typhimurium diversified with clade α lineages remained largely associated with multiple domesticated animal species, while clade β spawned multiple lineages that underwent diversifying selection associated with adaptation to various niches, predominantly in wild avian species.

scholarly journals Machine learning identifies signatures of host adaptation in the bacterial pathogen Salmonella enterica

2017 ◽  
Author(s):  
Nicole E. Wheeler ◽  
Paul P. Gardner ◽  
Lars Barquist
Keyword(s):  
Random Forest ◽  
Host Range ◽  
Salmonella Enterica ◽  
Bacterial Pathogen ◽  
Host Adaptation ◽  
Random Forest Classifier ◽  
Sub Saharan Africa ◽  
Broad Host Range ◽  
Invasive Infection ◽  
Emerging Pathogens

AbstractEmerging pathogens are a major threat to public health, however understanding how pathogens adapt to new niches remains a challenge. New methods are urgently required to provide functional insights into pathogens from the massive genomic data sets now being generated from routine pathogen surveillance for epidemiological purposes. Here, we measure the burden of atypical mutations in protein coding genes across independently evolved Salmonella enterica lineages, and use these as input to train a random forest classifier to identify strains associated with extraintestinal disease. Members of the species fall along a continuum, from pathovars which cause gastrointestinal infection and low mortality, associated with a broad host-range, to those that cause invasive infection and high mortality, associated with a narrowed host range. Our random forest classifier learned to perfectly discriminate long-established gastrointestinal and invasive serovars of Salmonella. Additionally, it was able to discriminate recently emerged Salmonella Enteritidis and Typhimurium lineages associated with invasive disease in immunocompromised populations in sub-Saharan Africa, and within-host adaptation to invasive infection. We dissect the architecture of the model to identify the genes that were most informative of phenotype, revealing a common theme of degradation of metabolic pathways in extraintestinal lineages. This approach accurately identifies patterns of gene degradation and diversifying selection specific to invasive serovars that have been captured by more labour-intensive investigations, but can be readily scaled to larger analyses.

scholarly journals The Microbial Lipopeptide Paenibacterin Disrupts Desiccation Resistance in Salmonella enterica Serovars Tennessee and Eimsbuettel

2019 ◽  
Vol 85 (14) ◽  
Author(s):  
Ahmed G. Abdelhamid ◽  
Ahmed E. Yousef
Keyword(s):  
Salmonella Enterica ◽  
Health Hazard ◽  
Active Agent ◽  
Resistance Mechanisms ◽  
Food Preservation ◽  
Control Measures ◽  
Dependent Manner ◽  
Desiccation Resistance ◽  
Concentration Dependent Manner ◽  
Content Type

ABSTRACT Salmonella enterica is increasingly linked to disease outbreaks associated with consumption of low-water-activity (low-aw) foods. Persistence of the pathogen in these foods was attributed to its ability to implement desiccation resistance mechanisms. Published knowledge about methods that disrupt desiccation resistance in S. enterica is lacking. We hypothesize that strong membrane-active compounds disrupt the desiccation resistance that S. enterica may acquire in low-aw foods or environments. The newly discovered antimicrobial lipopeptide paenibacterin was the membrane-active agent investigated in this study. Strains of S. enterica serovars Tennessee and Eimsbuettel, with a history of association with low-moisture foods, were investigated. The viability of these strains did not decrease significantly during dehydration and subsequent storage in the dehydrated state. Considering that the paenibacterin MIC against S. enterica strains was 8 μg/ml, concentrations of 4 to 16 μg/ml paenibacterin were tested. Within this range, desiccation-adapted S. Eimsbuettel was much more tolerant to the antimicrobial agent than the desiccation-adapted S. Tennessee. Pretreatment with 8 μg/ml paenibacterin increased inactivation of S. enterica during desiccation. The use of paenibacterin at 16 μg/ml or higher concentrations resulted in leakage of intracellular potassium ions from desiccation-adapted cells. Paenibacterin significantly decreased the biosynthesis of the intracellular osmoprotectant solute, trehalose, in a concentration-dependent manner. Treatment with 64 μg/ml paenibacterin increased the permeability of the cytoplasmic membranes of desiccation-adapted cells. Transcription of the desiccation-related genes proV, STM1494, kdpA, and otsB in response to paenibacterin treatment was investigated using reverse transcription-quantitative PCR. Transcription of some of these genes was downregulated in a concentration- and strain-dependent manner. IMPORTANCE Salmonella enterica adapts effectively and persists for a long time in low-aw foods or environments through resistance mechanisms to desiccation stress. Desiccation-resistant cells compromise food safety and constitute a serious health hazard. Strategies to combat desiccation resistance in S. enterica are needed to sensitize the pathogen to lethal processes used in food preservation. The study proved that the membrane-active lipopeptide paenibacterin disrupts the resistance in desiccation-adapted S. enterica, as measured by phenotypic, biochemical, and genetic analyses. This study highlighted the role of the lipopeptide paenibacterin in disrupting mechanisms employed by S. enterica to resist desiccation. This knowledge may lead to the design of novel control measures to improve the safety of low-aw foods.

Case-fatality of hand, foot and mouth disease associated with EV71: a systematic review and meta-analysis

2015 ◽  
Vol 143 (14) ◽  
pp. 3094-3102 ◽  
Author(s):  
Y. Y. ZHAO ◽  
H. JIN ◽  
X. F. ZHANG ◽  
B. WANG
Keyword(s):  
Random Effects ◽  
Meta Analysis ◽  
Enterovirus 71 ◽  
Case Fatality ◽  
Foot And Mouth Disease ◽  
Model Potential ◽  
Mouth Disease ◽  
Control Measures ◽  
Health Concern ◽  
Foot And Mouth

SUMMARYHand, foot and mouth disease (HFMD) associated with enterovirus 71 (EV71) is a growing public health concern. This study aimed to estimate the case-fatality of HFMD associated with EV71 on the basis of a meta-analysis. We searched PubMed, Cochrane, Web of Science, Elsevier, CNKI, Wanfang, and VIP databases. Two authors independently selected relevant studies. The pooled estimate of case-fatality was calculated using a random-effects model. Potential sources of heterogeneity were explored using subgroup analysis, sensitivity analysis and meta-regression. We identified 14 eligible studies with a total population of 112 546. The random-effects pooled case-fatality was 1·7% (95% confidence interval 1·2–2·4). The funnel plot was asymmetrical. The estimate of case-fatality was highest in mainland China (1·8%). Removal of eight local Chinese studies decreased the original estimate. The pooled case-fatality in the period of 1998–2007 (1·5%) was lower than that in the period 2008–2012 (1·8%). Control measures for HFMD associated with EV71 are essential because of the increased case-fatality over time, especially in East Asia.

scholarly journals Host Restriction of Salmonella enterica Serotype Typhimurium Pigeon Isolates Does Not Correlate with Loss of Discrete Genes

2004 ◽  
Vol 186 (9) ◽  
pp. 2619-2628 ◽  
Author(s):  
Helene L. Andrews-Polymenis ◽  
Wolfgang Rabsch ◽  
Steffen Porwollik ◽  
Michael McClelland ◽  
Carlos Rosetti ◽  
...  
Keyword(s):  
Host Range ◽  
Dna Microarray ◽  
Salmonella Enterica ◽  
Broad Host Range ◽  
Fluid Accumulation ◽  
Host Restriction ◽  
Phage Types ◽  
Chromosomal Genes ◽  
Large Groups ◽  
Intestinal Persistence

ABSTRACT The definitive phage types (DT) 2 and 99 of Salmonella enterica serotype Typhimurium are epidemiologically correlated with a host range restricted to pigeons, in contrast to phage types with broader host ranges such as epidemic cattle isolates (DT104 and DT204). To determine whether phage types with broad host range possess genetic islands absent from host-restricted phage types, we compared the genomes of four pigeon isolates to serotype Typhimurium strain LT2 using a DNA microarray. Three of the four isolates tested caused fluid accumulation in bovine ligated ileal loops, but they had reduced colonization of liver and spleen in susceptible BALB/c mice and were defective for intestinal persistence in Salmonella-resistant CBA mice. The genomes of the DT99 and DT2 isolates were extremely similar to the LT2 genome, with few notable differences on the level of complete individual genes. Two large groups of genes representing the Fels-1 and Fels-2 prophages were missing from the DT2 and DT99 phage types we analyzed. One of the DT99 isolates examined was lacking a third cluster of five chromosomal genes (STM1555 to -1559). Results of the microarray analysis were extended using Southern analysis to a collection of 75 serotype Typhimurium clinical isolates of 24 different phage types. This analysis revealed no correlation between the presence of Fels-1, Fels-2, or STM1555 to -1559 and the association of phage types with different host reservoirs. We conclude that serotype Typhimurium phage types with broad host range do not possess genetic islands influencing host restriction, which are absent from the host-restricted pigeon isolates.

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