scholarly journals Occurrence of mcr-mediated colistin resistance in Salmonella clinical isolates in Thailand

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Sirirat Luk-in ◽  
Tanittha Chatsuwan ◽  
Naris Kueakulpattana ◽  
Ubolrat Rirerm ◽  
Dhammika Leshan Wannigama ◽  
...  
Keyword(s):  
Clinical Isolates ◽  
High Rate ◽  
Foodborne Illnesses ◽  
Colistin Resistance ◽  
High Agreement ◽  
Plasmid Analysis ◽  
Dramatic Rise ◽  
Potential Reservoir ◽  
Increasing Trends ◽  
First Time

AbstractNontyphoidal Salmonella, an important zoonotic pathogen and a major cause of foodborne illnesses, could be a potential reservoir of plasmids harbouring mobile colistin resistance gene (mcr). This study reported, for the first time, a high rate of mcr-carrying Salmonella clinical isolates (3.3%, 24/724) in Thailand, associated with mcr-3 gene (3.0%, 22/724) in S. 4,[5],12:i:-(15.4%, 4/26), S. Typhimurium (8.8%, 5/57), and S. Choleraesuis (5.6%, 13/231). Remarkably, the increasing trends of colistin and extended-spectrum cephalosporin resistances have displayed a high agreement over the years, with a dramatic rise in the mcr-carrying Salmonella from 1.1% (6/563) during 2005–2007 to 11.2% (18/161) during 2014–2018 when CTX-M-55 became abundant. Clonal and plasmid analysis revealed that the self-transferable IncA/C and a novel hybrid IncA/C-FIIs MDR plasmids were the major vehicles to disseminate both mcr-3 and blaCTX-M55 genes among diverse Salmonella strains, from as early as 2007. To our knowledge the occurrence of mcr-3 and the co-existence of it with blaCTX-M-55 in S. Choleraesuis are reported here for the first time, leading to clinical concern over the treatment of the invasive salmonellosis. This study provides evidence of the potential reservoirs and vectors in the dissemination of the mcr and highlights the co-selection by colistin and/or cephalosporins.

scholarly journals First Report of blaNDM-1 Bearing IncX3 Plasmid in Clinically Isolated ST11 Klebsiella pneumoniae from Pakistan

2021 ◽  
Vol 9 (5) ◽  
pp. 951
Author(s):  
Hazrat Bilal ◽  
Gaojian Zhang ◽  
Tayyab Rehman ◽  
Jianxion Han ◽  
Sabir Khan ◽  
...  
Keyword(s):  
Sequence Type ◽  
The Other ◽  
High Rate ◽  
Antibiotics Resistance ◽  
New Delhi ◽  
Molecular Type ◽  
Plasmid Analysis ◽  
First Time ◽  
Encoding Genes ◽  
Sequence Types

The New Delhi Metallo-β-lactamase (NDM) is among the most threatening forms of carbapenemases produced by K. pneumoniae, well-known to cause severe worldwide infections. The molecular epidemiology of blaNDM-1-harboring K. pneumoniae is not well elucidated in Pakistan. Herein, we aim to determine the antibiotics-resistance profile, genes type, molecular type, and plasmid analysis of 125 clinically isolated K. pneumoniae strains from urine samples during July 2018 to January 2019 in Pakistan. A total of 34 (27.2%) K. pneumoniae isolates were carbapenemases producers, and 23 (18.4%) harbored the blaNDM-1 gene. The other carbapenemases encoding genes, i.e., blaIMP-1 (7.2%), blaVIM-1 (3.2%), and blaOXA-48 (2.4%) were also detected. The Multi Locus Sequence Typing (MLST) results revealed that all blaNDM-1-harboring isolates were ST11. The other sequence types detected were ST1, ST37, and ST105. The cluster analysis of Xbal Pulsed Field Gel Electrophoresis (PFGE) revealed variation amongst the clusters of the identical sequence type isolates. The blaNDM-1 gene in all of the isolates was located on a 45-kb IncX3 plasmid, successfully transconjugated. For the first time, blaNDM-1-bearing IncX3 plasmids were identified from Pakistan, and this might be a new primary vehicle for disseminating blaNDM-1 in Enterobacteriaceae as it has a high rate of transferability.

scholarly journals Serotype Is Associated With High Rate of Colistin Resistance Among Clinical Isolates of Salmonella

2020 ◽  
Vol 11 ◽  
Author(s):  
Qixia Luo ◽  
Yuan Wang ◽  
Hao Fu ◽  
Xiao Yu ◽  
Beiwen Zheng ◽  
...  
Keyword(s):  
Clinical Microbiology ◽  
Core Genome ◽  
Clinical Isolates ◽  
High Rate ◽  
Clinical Microbiology Laboratory ◽  
Nucleotide Polymorphisms ◽  
Microbiology Laboratory ◽  
Colistin Resistance ◽  
Single Nucleotide ◽  
Blood Samples

To investigate the prevalence, probable mechanisms and serotype correlation of colistin resistance in clinical isolates of Salmonella from patients in China, Salmonella isolates were collected from fecal and blood samples of patients. In this study, 42.8% (136/318) clinical isolated Salmonella were resistant to colistin. MIC distribution for colistin at serotype level among the two most prevalent serotypes originating from humans in China indicated that Salmonella Enteritidis (83.9% resistance, 125/149) were significantly less susceptible than Salmonella Typhimurium (15.3% resistance, 9/59, P < 0.01). mcr genes and mutations in PmrAB confer little for rate of colistin resistant Salmonella isolated from human patients. Phylogenetic tree based on core-genome single nucleotide polymorphisms (SNPs) was separately by the serotypes and implied a diffused distribution of MICs in the same serotype isolates. Relatvie expression levels of colistin resistant related pmr genes were significantly higher in non-mcr colistin resistant S. Typhimurium than in colistin sensitive S. Typhimurium, but no discernable differences between colistin resistant and sensitive S. Enteritidis, indicating a different mechanism between colistin resistant S. Typhimurium and S. Enteritidis. In conclusion, colistin susceptibility and colistin resistant mechanism of clinical isolated Salmonella were closely associated with specific serotypes, at least in the two most prevalent serotype Enteritidis and Typhimurium. We suggest clinical microbiology laboratory interpreting Salmonella colistin MIC results in the serotype level.

scholarly journals SOI-Based Multi-Channel AWG with Fiber Bragg Grating Sensing Interrogation System

Photonics ◽  
2021 ◽  
Vol 8 (6) ◽  
pp. 214
Author(s):  
Siming Weng ◽  
Pei Yuan ◽  
Wei Zhuang ◽  
Dongliang Zhang ◽  
Fei Luo ◽  
...  
Keyword(s):  
Fiber Bragg Grating ◽  
Dynamic Range ◽  
High Dynamic Range ◽  
High Rate ◽  
Bragg Grating ◽  
Arrayed Waveguide Grating ◽  
High Agreement ◽  
High Dynamic ◽  
Critical Components ◽  
Arrayed Waveguide

For the development of minimized and high-rate photonic-integrated fiber Bragg grating interrogation (FBGI) systems, arrayed waveguide grating (AWG) has been widely used as one of the critical components. In this paper, we present an 8-channel SOI-based AWG for a photonic integrated FBG interrogation microsystem. The channel spacing of the AWG is designed to be 3 nm to meet a high-dynamic-range demodulation requirement. The core size of the fabricated AWG is about 335 × 335 μm2. The simulation results and experimental results are in high agreement, showing that AWG has a fine transmission spectrum with crosstalk below −16 dB, nonuniformity below 0.4 dB, insertion loss below −6.35 dB, 3 dB bandwidth about 1.3 nm and 10 dB bandwidth of 2.3 nm. The proposed AWG can be applied perfectly to the SOI-based AWG demodulation microsystem, exhibiting a large dynamic range of 1.2 nm, the resolution for measurements is 1.27 pm and a high accuracy of 20.6 pm.

scholarly journals Risk Factors for and Mechanisms of COlistin Resistance Among Enterobacterales: Getting at the CORE of the Issue

2021 ◽  
Author(s):  
John P Mills ◽  
Laura J Rojas ◽  
Steve H Marshall ◽  
Susan D Rudin ◽  
Andrea M Hujer ◽  
...  
Keyword(s):  
Case Control Study ◽  
Clinical Isolates ◽  
Colistin Resistance ◽  
E Coli ◽  
The Core ◽  
Increased Risk ◽  
Recent Emergence ◽  
Enterobacter Species ◽  
Ann Arbor ◽  
Control Study

Abstract Background Despite the recent emergence of plasmid-mediated colistin resistance, the epidemiology and mechanisms of colistin-resistant Enterobacterales (CORE) infections remain poorly understood. Methods A case-case-control study was conducted utilizing routine clinical isolates obtained at a single tertiary health system in Ann Arbor, MI. Patients with CORE isolates from January 1st 2016 to March 31st 2017 were matched 1:1 with patients with colistin-susceptible Enterobacterales (COSE) and uninfected controls. Multivariable logistic regression was used to compare clinical and microbiologic features of patients with CORE and COSE to controls. A subset of available CORE isolates underwent whole genome sequencing to identify putative colistin resistance genes. Results Of 16,373 tested clinical isolates, 166 (0.99%) were colistin-resistant, representing 103 unique patients. Among 103 CORE isolates, 103 COSE isolates, and 102 uninfected controls, antibiotic exposure in the antecedent 90 days and age > 55 years were predictors of both CORE and COSE. Of 33 isolates that underwent WGS, a large variety of mutations associated with colistin resistance were identified, including 4 mcr-1/mcr-1.1 genes and 4 pmrA/B mutations among 9 Escherichia coli isolates; 5 mgrB and 3 PmrA mutations among 8 Klebsiella pneumoniae isolates. Genetic mutations found in Enterobacter species were not associated with known phenotypic colistin resistance. Conclusions Increased age and prior antibiotic receipt were associated with increased risk for patients with CORE, and for patients with COSE. Mcr-1, pmrA/B, and mgrB were the predominant colistin resistance-associated mutations identified among E. coli and K. pneumoniae, respectively. Mechanisms of colistin resistance among Enterobacter species could not be determined.

scholarly journals A Prospective Study of Acinetobacter baumannii Complex Isolates and Colistin Susceptibility Monitoring by Mass Spectrometry of Microbial Membrane Glycolipids

2018 ◽  
Vol 57 (3) ◽  
Author(s):  
Lisa M. Leung ◽  
Christi L. McElheny ◽  
Francesca M. Gardner ◽  
Courtney E. Chandler ◽  
Sarah L. Bowler ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Acinetobacter Baumannii ◽  
Lipid A ◽  
Membrane Lipids ◽  
Clinical Isolates ◽  
Colistin Resistance ◽  
Hospital System ◽  
Content Type ◽  
Acinetobacter Baumannii Complex ◽  
Gram Negative Organisms

ABSTRACT Acinetobacter baumannii is a prevalent nosocomial pathogen with a high incidence of multidrug resistance. Treatment of infections due to this organism with colistin, a last-resort antibiotic of the polymyxin class, can result in the emergence of colistin-resistant strains. Colistin resistance primarily occurs via modifications of the terminal phosphate moieties of lipopolysaccharide-derived lipid A, which reduces overall membrane electronegativity. These modifications are readily identified by mass spectrometry (MS). In this study, we prospectively collected Acinetobacter baumannii complex clinical isolates from a hospital system in Pennsylvania over a 3-year period. All isolates were evaluated for colistin resistance using standard MIC testing by both agar dilution and broth microdilution, as well as genospecies identification and lipid A profiling using MS analyses. Overall, an excellent correlation between colistin susceptibility and resistance, determined by MIC testing, and the presence of a lipid A modification, determined by MS, was observed with a sensitivity of 92.9% and a specificity of 94.0%. Additionally, glycolipid profiling was able to differentiate A. baumannii complex organisms based on their membrane lipids. With the growth of MS use in clinical laboratories, a reliable MS-based glycolipid phenotyping method that identifies colistin resistance in A. baumannii complex clinical isolates, as well as other Gram-negative organisms, represents an alternative or complementary approach to existing diagnostics.

scholarly journals Prevalence and Molecular Characterization of mcr-1-Positive Salmonella Strains Recovered from Clinical Specimens in China

2017 ◽  
Vol 61 (5) ◽  
Author(s):  
Mingquan Cui ◽  
Jinfei Zhang ◽  
Zhen Gu ◽  
Ruichao Li ◽  
Edward Wai-chi Chan ◽  
...  
Keyword(s):  
Pulsed Field Gel Electrophoresis ◽  
Clinical Settings ◽  
Colistin Resistance ◽  
Content Type ◽  
Transmission Potential ◽  
Conjugative Plasmids ◽  
Plasmid Analysis ◽  
Antimicrobial Resistance Genes ◽  
Pfge Profiles

ABSTRACT The recently discovered colistin resistance element, mcr-1, adds to the list of antimicrobial resistance genes that rapidly erode the antimicrobial efficacy of not only the commonly used antibiotics but also the last-line agents of carbapenems and colistin. This study investigated the prevalence of the mobile colistin resistance determinant mcr-1 in Salmonella strains recovered from clinical settings in China and the transmission potential of mcr-1-bearing mobile elements harbored by such isolates. The mcr-1 gene was recoverable in 1.4% of clinical isolates tested, with the majority of them belonging to Salmonella enterica serotype Typhimurium. These isolates exhibited diverse pulsed-field gel electrophoresis (PFGE) profiles and high resistance to antibiotics other than colistin and particularly to cephalosporins. Plasmid analysis showed that mcr-1 was carried on a variety of plasmids with sizes ranging from ∼30 to ∼250 kb, among which there were conjugative plasmids of ∼30 kb, ∼60 kb, and ∼250 kb and nonconjugative plasmids of ∼140 kb, ∼180 kb, and ∼240 kb. Sequencing of representative mcr-1-carrying plasmids revealed that all conjugative plasmids belonged to the IncX4, IncI2, and IncHI2 types and were highly similar to the corresponding types of plasmids reported previously. Nonconjugative plasmids all belonged to the IncHI2 type, and the nontransferability of these plasmids was attributed to the loss of a region carrying partial or complete tra genes. Our data revealed that, similar to the situation in Escherichia coli, mcr-1 transmission in Salmonella was accelerated by various plasmids, suggesting that transmission of mcr-1-carrying plasmids between different species of Enterobacteriaceae may be a common event.

Ground Beef Consumption Patterns in the United States, FoodNet, 2006 through 2007

2012 ◽  
Vol 75 (2) ◽  
pp. 341-346 ◽  
Author(s):  
ETHEL V. TAYLOR ◽  
KRISTIN G. HOLT ◽  
BARBARA E. MAHON ◽  
TRACY AYERS ◽  
DAWN NORTON ◽  
...  
Keyword(s):  
United States ◽  
Foodborne Pathogens ◽  
College Education ◽  
Ground Beef ◽  
The United States ◽  
High Rate ◽  
Foodborne Illnesses ◽  
Beef Patties ◽  
Uremic Syndrome ◽  
Using Data

Infection resulting from foodborne pathogens, including Escherichia coli O157:H7, is often associated with consumption of raw or undercooked ground beef. However, little is known about the frequency of ground beef consumption in the general population. The objective of this study was to describe patterns of self-reported ground beef and pink ground beef consumption using data from the 2006 through 2007 FoodNet Population Survey. From 1 July 2006 until 30 June 2007, residents of 10 FoodNet sites were contacted by telephone and asked about foods consumed within the previous week. The survey included questions regarding consumption of ground beef patties both inside and outside the home, the consumption of pink ground beef patties and other types of ground beef inside the home, and consumption of ground beef outside the home. Of 8,543 survey respondents, 75.3% reported consuming some type of ground beef in the home. Of respondents who ate ground beef patties in the home, 18.0% reported consuming pink ground beef. Consumption of ground beef was reported most frequently among men, persons with incomes from $40,000 to $75,000 per year, and persons with a high school or college education. Ground beef consumption was least often reported in adults ≥65 years of age. Men and persons with a graduate level education most commonly reported eating pink ground beef in the home. Reported consumption of ground beef and pink ground beef did not differ by season. Ground beef is a frequently consumed food item in the United States, and rates of consumption of pink ground beef have changed little since previous studies. The high rate of consumption of beef that has not been cooked sufficiently to kill pathogens makes pasteurization of ground beef an important consideration, especially for those individuals at high risk of complications from foodborne illnesses such as hemolytic uremic syndrome.

scholarly journals Blood Transfusion Service and Hospital Blood Rotation: The Implications on Transfusion Safety in Nigeria

2019 ◽  
Vol 2 (1) ◽  
pp. 19-24
Author(s):  
O D Damulak ◽  
E D Jatau ◽  
E Ekam ◽  
E Rumji ◽  
R Yakubu ◽  
...  
Keyword(s):  
Blood Transfusion ◽  
Diagnostic Test ◽  
Rapid Diagnostic Test ◽  
Blood Donors ◽  
Blood Donation ◽  
Tertiary Hospital ◽  
Sub Saharan Africa ◽  
High Rate ◽  
Blood Transfusion Service ◽  
First Time

Blood donation is not readily an altruistic sacrifice in sub-Saharan Africa where microbial infections, maternal haemorrhages, malaria and other tropical diseases that frequently require blood transfusion are daily diagnoses. Blood transfusion safety is hindered by the combined prevailing high rate of Transfusion-Transmissible Infections (TTIs) and poor screening techniques. This study determined the rate of Enzyme-Linked Immuno-Sorbent Assay (ELISA) positive reactions to transfusion-transmissible infections in rapid diagnostic test negative family replacement blood units, compared to the first time voluntarily donated blood. We studied records of blood units collected in a tertiary hospital from donors who scaled pre-donation Rapid diagnostic test (RDT) screening for the human immunodeficiency virus, hepatitis B and hepatitis C viruses and syphilis and rescreened by ELISA techniques at the National Blood Transfusion Service Centre in Jos, along with units from first-time voluntary blood donors. A total of 19562 blood units; 5945 (30.39%) rapid diagnostic tests negative from a linkage hospital and 13617 (69.61%) from first time voluntary donors were screened by ELISA methods for HIV, HBV, HCV, and syphilis. The overall TTIs detected by ELISA was 16.08%, significantly lower among pre-donation rapid screened family replacement blood donors [495(8.32%)] compared to 2651 (19.47%) among first-time voluntary donors; P=0.0001. Fifty-seven (0.96%) HIV, 166 (2.79%) HBV, 137 (2.31%) HCV and 137 (2.31%) syphilis were still detected respectively by ELISA in the pre-screened negative family replacement blood units. The outcome of ELISA screenings of blood collected from first-time volunteer donors were; 143 (1.05%) HIV, 1,486 (10.91%) HBV, 683 (5.02%) HCV, and 339 (2.49%) syphilis. Blood for transfusion should be screened negative at least with ELISA.

Vaccination Against COVID-19: Emerging Issues and Future Prospects

2021 ◽  
Vol 76 (6) ◽  
pp. 652-660
Author(s):  
Gennadiy G. Onischenko ◽  
Tatiana E. Sizikova ◽  
Vitaliy N. Lebedev ◽  
Sergey V. Borisevich
Keyword(s):  
Effective Means ◽  
Herd Immunity ◽  
High Rate ◽  
Vaccination Rates ◽  
Actual Duration ◽  
Entire Duration ◽  
Mass Immunization ◽  
Emerging Issues ◽  
First Time

The most effective means of combating the COVID-19 pandemic s the formation of herd immunity, with the formation of an immune population to infection. Vaccination rates are continuously increasing. In early February 2021, WHO announced that the number of people vaccinated against the disease for the first time exceeded the number of infected. In early June 2021 the vaccinated number exceeded 2 billion which is more than 12 times the total number infected for the entire duration of the pandemic. The high rate of vaccination leads to the formulation of a number of questions concerning the effectiveness of vaccines currently used for mass immunization the level of herd immunity, necessary to stop the spread of the disease, the actual duration of the vaccination carried out, long-term prospects of the platforms, used in the creation of vaccines. The purpose of this paper is to substantiate reasoned answers to the questions posed.

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