Hermine Mkrtchyan

Dr. Hermine Mkrtchyan


Research Focus & Metrics

Academic Career Length

11Years (2016-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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13 June 2018 in Antimicrobial Resistance & Infection Control
Verified
Journal Article
Open access
PDF file
ZXZhen Xu
Zhen Xu
HSHaroun N. Shah
Haroun N. Shah
RMRaju Misra
Raju Misra
JCJiazhen Chen
Jiazhen Chen
WZWen-Hong Zhang
Wen-Hong Zhang
HMHermine Mkrtchyan
Hermine Mkrtchyan
Background: Coagulase negative staphylococci (CoNS) are important reservoirs of antibiotic resistance genes and associated mobile genetic elements and are believed to contribute to the emergence of successful methicillin resistant Staphylococcus aureus (MRSA) clones. Although, these bacteria have been linked to various ecological niches, little is known about the dissemination and genetic diversity of antibiotic resistant CoNS in general public settings. Methods: Four hundred seventy-nine samples were collected from different non-healthcare/general public settings in various locations (n = 355) and from the hands of volunteers (n = 124) in London UK between April 2013 and Nov 2014. Results: Six hundred forty-three staphylococcal isolates belonging to 19 staphylococcal species were identified. Five hundred seventy-two (94%) isolates were resistant to at least one antibiotic, and only 34 isolates were fully susceptible. Sixty-eight (11%) mecA positive staphylococcal isolates were determined in this study. SCCmec types were fully determined for forty-six isolates. Thirteen staphylococci (19%) carried SCCmec V, followed by 8 isolates carrying SCCmec type I (2%), 5 SCCmec type IV (7%), 4 SCCmec type II (6%), 1 SCCmec type III (2%), 1 SCCmec type VI (2%), and 1 SCCmec type VIII (2%). In addition, three isolates harboured a new SCCmec type 1A, which carried combination of class A mec complex and ccr type 1. MLST typing revealed that all S. epidermidis strains possess new MLST types and were assigned the following new sequence types: ST599, ST600, ST600, ST600, ST601, ST602, ST602, ST603, ST604, ST605, ST606, ST607 and ST608. Conclusions: The prevalence of antibiotic resistant staphylococci in general public settings demonstrates that antibiotics in the natural environments contribute to the selection of antibiotic resistant microorganisms. The finding of various SCCmec types in non-healthcare associated environments indicates the complexity of SCCmec. We also report on new MLST types that were assigned for all S. epidermidis isolates, which demonstrates the genetic variability of these isolates.

31 August 2021 in Environment International
Verified
Journal Article
Open access
RCRory Cave
Rory Cave
JCJennifer Cole
Jennifer Cole
HMHermine Mkrtchyan
Hermine Mkrtchyan
Antimicrobial resistant (AMR) bacteria present one of the biggest threats to public health; this must not be forgotten while global attention is focussed on the COVID-19 pandemic. Resistant bacteria have been demonstrated to be transmittable to humans in many different environments, including public settings in urban built environments where high-density human activity can be found, including public transport, sports arenas and schools. However, in comparison to healthcare settings and agriculture, there is very little surveillance of AMR in the built environment outside of healthcare settings and wastewater. In this review, we analyse the existing literature to aid our understanding of what surveillance has been conducted within different public settings and identify what this tells us about the prevalence of AMR. We highlight the challenges that have been reported; and make recommendations for future studies that will help to fill knowledge gaps present in the literature.

1 August 2019 in Scientific Reports
Verified
Journal Article
Open access
PDF file
RCRory Cave
Rory Cave
RMRaju Misra
Raju Misra
JCJiazhen Chen
Jiazhen Chen
SWShiyong Wang
Shiyong Wang
HMHermine Mkrtchyan
Hermine Mkrtchyan
The rise of antibiotic resistance (AMR) is one of the most important public health threats worldwide.Today, increasing attention is being paid to multidrug resistant staphylococci isolated from healthcare and non-healthcare environments as the treatment of these bacteria has become increasingly difficult. In this study, we compared staphylococci isolates recovered from high frequency touched surfaces from public areas in the community and hospitals in East and West London. 281 out of 600 (46.83%) staphylococci isolates recovered were multidrug resistant, of which 49 (8.17%) were mecA positive. There was significantly higher proportion of multidrug resistant staphylococci (P = 0.0002) in East London (56.7%) compared to West London (49.96%). The most common species identified as multidrug resistant were S. epidermidis, S. haemolyticus and S. hominis, whereas penicillin, fusidic acid and erythromycin were the most frequent antibiotics the isolates were resistant to. Whole genome sequenced of mecA positive isolates revealed that S. sciuri isolates carried the mecA1 gene, which has only 84.43% homology with mecA. In addition, other frequently identified resistance genes included blaZ, qacA/B and dfrC. We have also identified a diverse range of SCCmec types, many of which were untypable due to carrying a novel combination of ccr genes or multiple ccr complexes.

1 July 2018 in G3: Genes, Genomes, Genetics
Verified
Journal Article
Open access
PDF file
ZXZhen Xu
Zhen Xu
RMRaju Misra
Raju Misra
DJDorota Jamrozy
Dorota Jamrozy
GPGavin Paterson
Gavin Paterson
RCRonald R. Cutler
Ronald R. Cutler
HMHermine Mkrtchyan
Hermine Mkrtchyan
Staphylococcus epidermidis is a major opportunistic pathogen primarily recovered from device-associated healthcare associated infections (DA-HAIs). Although S. epidermidis and other coagulase-negative staphylococci (CoNS) are less virulent than Staphylococcus aureus, these bacteria are an important reservoir of antimicrobial resistance genes and resistance-associated mobile genetic elements that can be transferred between staphylococcal species. We report a whole genome sequence of a multidrug resistant S. epidermidis (strain G6_2) representing multilocus sequence type (ST) 59 and isolated from an environmental sampling of a hotel room in London, UK. The genome of S. epidermidis G6_2 comprises of a 2408357 bp chromosome and six plasmids, with an average G+C content of 32%. The strain displayed a multi-drug resistance phenotype which was associated with carriage of 7 antibiotic resistance genes (blaZ, mecA, msrA, mphC, fosB, aacA-aphD, tetK) as well as resistance-conferring mutations in fusA and ileS. Antibiotic resistance genes were located on plasmids and chromosome. Comparative genomic analysis revealed that antibiotic resistance gene composition found in G6_2 was partly preserved across the ST59 lineage.

1 September 2020 in Journal of Global Antimicrobial Resistance
Verified
Journal Article
Open access
ZXZhen Xu
Zhen Xu
RCRory Cave
Rory Cave
LCLiqin Chen
Liqin Chen
TYTsetan Yangkyi
Tsetan Yangkyi
YLYan Liu
Yan Liu
HMHermine Mkrtchyan
Hermine Mkrtchyan
Staphylococcus epidermidis is a major nosocomial pathogen predominantly associated with indwelling medical device infections. Studies reporting on S. epidermidis recovered from hospital personnel in China are scarce. The aim of this study was to evaluate the carriage and antibiotic resistance of S. epidermidis among the hospital personnel in Tianjin, China and provide insights into their genetic diversity. 107 S. epidermidis isolates were recovered from 68 hospital personnel in two public hospitals in Tianjin between March 2018 and May 2018. SCCmec types were determined by the combination of mec and ccr complexes. Multi-locus sequence typing was used to determine the sequence types (ST) of S. epidermidis isolates. 62 (76.5%) isolates were determined to be methicillin-resistant S. epidermidis (MRSE). 35 (51%) out of 68 hospital personnel carried S. epidermidis, of which 32 (91%) were carriers of MRSE. All 62 MRSE isolates had high levels of resistance to penicillin (90%) and cefoxitin (100%). 37 (60%) isolates carried SCCmec type IV, followed by 15 (24%) carrying SCCmec V, and 4 (6%) SCCmec II. Novel sequence types were assigned to four S. epidermidis isolates (ST832, ST833, ST834 and ST835). In this study, the majority of MRSE belonged to cluster II domain of CC2. The ST59-IV was a dominant clone among isolates recovered from hospital personnel. Determination of new MLST types confirmed the genetic diversity of these isolates. These observations highlight the need to review the infection control strategies to reduce the carriage of MRSE among hospital personnel.

31 August 2022 in Microbiology Spectrum
Verified
Journal Article
Open access
Wael El-DeebWael El-Deeb
Wael El-Deeb
RCRory Cave
Rory Cave
MFMahmoud Fayez
Mahmoud Fayez
NANaser Alhumam
Naser Alhumam
SQSayed Quadri
Sayed Quadri
HMHermine Mkrtchyan
Hermine Mkrtchyan
Our findings demonstrate a possible cross-transmission of methicillin resistant staphylococci between goats and their local environments and between goats and humans. Due to ever increasing resistance to multiple antibiotics, the burden of MRS has a significant impact on livestock farming, public health, and the economy worldwide.