Prevalence of Methicillin Resistant Staphylococcal Bioaerosols in and around Residential Houses in an Urban Area in Central India

Methicillin resistant staphylococci (MRS) commonly found in clinical samples or associated environment pose a major health challenge globally. The carriage rate of MRS in human population is high, especially in India but research on airborne distribution of MRS is scanty. The present study aimed to evaluate the prevalence of MRS in indoor and outdoor environment of residential houses. Air samples were collected using impactor air sampler. The total counts of viable bacteria, staphylococci, and MRS along with the particles of various sizes were determined from indoor and outdoor environment of 14 residential houses. MRS bacteria were identified as methicillin resistantS. aureus(MRSA) or coagulase negative staphylococci (CNS) employing biochemical and PCR assays. The average concentration of MRS inside and outside of the houses was 5.9% and 4.6% of the total bacteria, respectively. The maximum correlation of total indoor and outdoor bacteria with particulate matter was 10 μm (r=0.74) and 5 μm (r=0.84), respectively. Statistically, significant positive correlation of staphylococci and MRS was found with particles of 10–25 μm inside the houses. Molecular surveillance, antibiotic stewardship programme, and infection control policies can help to manage increasing MRS burden in developing countries.

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The Staphylococcal Cassette Chromosome mec (SCCmec) Analysis and Biofilm Formation of Methicillin-Resistant Staphylococcus cohnii Isolated from Clinical Samples in Tehran, Iran

Recent Patents on Anti-Infective Drug Discovery ◽

10.2174/1574891x16666210210101912 ◽

2021 ◽

Vol 16 ◽

Author(s):

Somaye Delfani ◽

Faranak Rezaei ◽

Setareh Soroush ◽

Pegah Shakib

Keyword(s):

Antibiotic Resistance ◽

Biofilm Formation ◽

Antibiotic Resistance Genes ◽

Mobile Element ◽

Diffusion Method ◽

Clinical Samples ◽

Coagulase Negative Staphylococci ◽

Methicillin Resistant ◽

Inducible Clindamycin Resistance ◽

Sccmec Types

Background: Methicillin-resistant coagulase-negative staphylococci is responsible for hospital and community-acquired infections. Objective: This study aimed to investigate the antibiotic-resistance patterns, antibiotic-resistance genes, namely, ermA, ermB, ermC, blaZ, msrA, tetK, tetM, mup, and vanA, biofilm formation, and prevalence of different SCCmec types among the Staphylococcus cohniistrains isolated from clinical samples in Tehran, Iran. Methods: In this study,S. cohniiisolates were screened from the clinical samples from March 2012 to February 2013 in Tehran, Iran.Antimicrobial susceptibility test and inducible clindamycin resistance were evaluated by disc diffusion method, andresistance genes were examined using Polymerase Chain Reaction (PCR) assays. Then, biofilm formation assay was analyzed by Microtiter-plate test to detect the icaA and icaDgenes. The SCCmec and the Arginine Catabolite Mobile Element (ACME) typing were performed using the PCRmethod. Results: FromtwentyS. cohnii, all isolates were resistant to cefoxitin. 95% of the S. cohnii was defined as multidrug resistance (MDR)strains. The ermB, ermC, and vanA genes were not detected in any isolates; however, the blaZ gene had the highest frequency.95% of the S. cohnii isolates produced biofilm. Also, 4 SCCmec types, including V, IV, III+ (C2), VIII+ (AB1), were identified. Therefore, the majority of SCCmec were untypable. Based on the ACME typing, arcA and opp3 genes were positive in 13 (65%) and 1 (5%) isolates, respectively. Conclusion: Due to the high antimicrobial resistance and the spread of untypableSCCmecamong the isolates studied, the control and treatment of methicillin-resistantS. cohnii in hospitals and public health centers is a significant concern.

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Drug-resistant coagulase-negative skin staphylococci: Evaluation of four marker systems and epidemiology in an orthopaedic ward

Epidemiology and Infection ◽

10.1017/s0950268800047695 ◽

1990 ◽

Vol 105 (1) ◽

pp. 95-105 ◽

Cited By ~ 23

Author(s):

M. Thore ◽

I. Kühn ◽

S. Löfdahl ◽

L. G. Burman

Keyword(s):

Drug Resistant ◽

Ward Staff ◽

Coagulase Negative Staphylococci ◽

Species Determination ◽

Carriage Rate ◽

Methicillin Resistant ◽

Orthopaedic Patients ◽

Orthopaedic Ward ◽

Combined Data

SUMMARYDrug-resistant coagulase-negative staphylococci (DRCNS) in orthopaedic patients and ward staff were studied. A significant increase in the DRCNS carriage rate was observed among the 16 patients studied after 14 days of hospitalization with levels approaching that of the staff. Patients receiving dicloxacillin prophylaxis (n=9) were more likely to be colonized with methicillin-resistant CNS, while patients receiving no antibiotics (n= 7) became to a larger extent colonized with multiple DRCNS. The combined data from species determination, biochemical, plasmid, and antibiogram typing revealed a considerable diversity among DRCNS;64 types were distinguished among 112 DRCNS isolates selected for study after exclusion of apparently duplicate isolates. Plasmid plus antibiogram typing yielded almost as many types (61); whereas species determination plus antibiogram distinguished only 33 types. Although a novel computerized 96-reaction boityping method alone enabled differentiation of 17 biotypes, most DRCNS isolates belonged to one of three major biotypes limiting the usefulness of this method. Ten of the 64 (16%) DRCNS types identified comprised 50 of the 112 (45%) isolates. These were isolated from staff and from patients on day 14, suggesting a nosocomial origin.

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The epidemiology and molecular characterization of methicillin-resistant staphylococci sampled from a healthy Jordanian population

Epidemiology and Infection ◽

10.1017/s0950268813000010 ◽

2013 ◽

Vol 141 (11) ◽

pp. 2384-2391 ◽

Cited By ~ 28

Author(s):

A. G. AL-BAKRI ◽

H. AL-HADITHI ◽

V. KASABRI ◽

G. OTHMAN ◽

A. KRIEGESKORTE ◽

...

Keyword(s):

Staphylococcus Epidermidis ◽

Nasal Carriage ◽

Control Measures ◽

Coagulase Negative Staphylococci ◽

Carriage Rate ◽

Methicillin Resistant ◽

Infection Control Measures ◽

Type Iv ◽

Encoding Genes

SUMMARYThe prevalence of natural carriage and molecular epidemiology of methicillin-resistantStaphylococcus aureus(MRSA) and methicillin-resistant coagulase-negative staphylococci (MR-CoNS) isolates in a Jordanian community were investigated. The MRSA nasal carriage rate in 227 healthy volunteers was 7·5% and the majority (81%) of MRSA harboured the resistance element SCCmectype IVe and were of a novelspatype t9519 (76%); other significantspagene types were t223 (14·7%) and t044 (5·9%). All MRSA isolates were susceptible to other classes of antibiotics, and tested positive for at least three virulence factor encoding genes, but only two harboured thepvlgene. MR-CoNS carriage was 54·2% and these isolates were characterized by single, double and untypable SCCmecelements, withStaphylococcus epidermidisSCCmectype IVa predominating. Of eight subjects with nasal co-colonization of MR-CoNS + MRSA, three shared SCCmectype IV in both groups of organisms. This is the first report of methicillin-resistant staphylococci carriage in a Jordanian community and its findings are important for epidemiological study and infection control measures of these organisms.

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Biofilm formation of methicillin-resistant coagulase-negative staphylococci isolated from clinical samples in Northern Thailand

Journal of Global Infectious Diseases ◽

10.4103/jgid.jgid_118_18 ◽

2019 ◽

Vol 11 (3) ◽

pp. 112 ◽

Cited By ~ 2

Author(s):

Sutthirat Sitthisak ◽

Thawatchai Kitti ◽

Rathanin Seng ◽

Rapee Thummeepak ◽

Chalermchai Boonlao ◽

...

Keyword(s):

Biofilm Formation ◽

Clinical Samples ◽

Coagulase Negative Staphylococci ◽

Northern Thailand ◽

Methicillin Resistant

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The Prevalence of antimicrobial resistance in Staphylococcus aureus and coagulase-negative Staphylococci strains isolated from inpatients

10.21203/rs.3.rs-24115/v2 ◽

2020 ◽

Author(s):

Parva Farmehr ◽

Javad fathi ◽

Mahtab Hadadi ◽

mohammad motamedifar

Keyword(s):

Staphylococcus Aureus ◽

Antimicrobial Susceptibility ◽

Antibacterial Agents ◽

Cross Sectional Study ◽

Clinical Samples ◽

Coagulase Negative Staphylococci ◽

Cross Sectional ◽

Antibiotic Policy ◽

Methicillin Resistant ◽

Southwest Of Iran

Abstract Objectives: Globally nosocomial infection is a significant problem. Methicillin resistant Staphylococcus aureus (MRSA) and Methicillin resistant coagulase negative staphylococci (MRCoNS) are major causes of nosocomial infections. Aim of this study was to determine the prevalence and antimicrobial susceptibility of MRSA and MRCoNS in the southwest of Iran. This cross-sectional study was conducted on 221 non-duplicated staphylococci isolates collected from teaching hospital in Shiraz. The prevalence of MRSA and MRCoNS in clinical samples was identified with conventional microbiological tests. After identification, all of the isolates were subjected to antimicrobial susceptibility test and PCR to identify the presence of femA, mecA and pvl genes. Results: 70 (41.7 %) MRSA among 168 S. aureus, and 26 (15.48%) MRCoNS among 53 CoNS were examined. All of the isolates were susceptible to Trimethoprim/Sulfamethoxazole (100%). Chloramphenicol (65%) and Gentamicin (23%) were the other most active antibacterial agents against MRSA and MRCoNS. The frequency of pvl gene among S. aureus strains was 3.57%. There is need for developing the antibiotic policy and limiting the use of powerful antibiotics.

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The SCCmec Types and Antimicrobial Resistance among Methicillin-Resistant Staphylococcus Species Isolated from Dogs with Superficial Pyoderma

Veterinary Sciences ◽

10.3390/vetsci8050085 ◽

2021 ◽

Vol 8 (5) ◽

pp. 85

Author(s):

Yuttana Chanayat ◽

Areerath Akatvipat ◽

Jeff B. Bender ◽

Veerasak Punyapornwithaya ◽

Tongkorn Meeyam ◽

...

Keyword(s):

Antimicrobial Susceptibility ◽

Sccmec Type ◽

Small Animal ◽

Control Measures ◽

Infection Prevention And Control ◽

Clinical Samples ◽

Biochemical Tests ◽

Methicillin Resistant ◽

Type V ◽

Staphylococcal Cassette Chromosome

This study characterizes clinical methicillin-resistant staphylococcal (MRS) isolates obtained from superficial pyoderma infections in dogs. Our interest was to determine the staphylococcal cassette chromosome mec (SCCmec) type and the antimicrobial susceptibility among MRS isolates from clinical cases. Skin swabs were collected and cultured. Staphylococcus species were identified and characterized with biochemical tests and MALDI-TOF-MS and antimicrobial susceptibility testing by disk diffusion. mecA detection and staphylococcal cassette chromosome mec (SCCmec) typing were achieved by PCR. Of the 65 clinical samples, 56 (86.2%) staphylococcal infections were identified. Twelve (21%) of 56 isolates were MRS infections. All MRS isolates were multidrug resistant. The ccrC and class-C2 mec, which were SCCmec type V, were the most prevalent (66.7%) among the 12 MRS isolates. The predominant SCCmec type V was found in S. aureus, S. intermedius group, S. lentus, S. xylosus, and S. arlettae. Treatment failure is a concern with the emergence of highly resistant MRS in dogs associated with superficial pyoderma. The detection of type V SCCmec MRS has previously been reported among veterinarians and dog owners but not in Northern Thailand. These infections serve as a reminder to improve infection prevention and control measures including reducing environmental contamination and potential zoonotic exposures to MRS. In addition, educational awareness of these risks in small animal hospitals needs to be increased among veterinary hospital staff, clients, and patients.

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Assessment of Indoor Benzene and Its Alkyl Derivatives Concentrations in Offices Belonging to University of Technology (Poland)

Atmosphere ◽

10.3390/atmos12010051 ◽

2020 ◽

Vol 12 (1) ◽

pp. 51

Author(s):

Barbara Kozielska ◽

Dorota Kaleta

Keyword(s):

Dominant Role ◽

Average Concentration ◽

Air Contamination ◽

Flame Ionization ◽

Indoor Sources ◽

Alkyl Derivatives ◽

University Of Technology ◽

Low Concentrations ◽

Office Rooms ◽

Indoor And Outdoor

Indoor air contamination in office rooms is regarded as one of the most important issues in the protection of workers’ health, because contaminants, even those occurring at low concentrations, can cause health problems for the office staff in view of the long exposure time. This paper presents the results of measurements of benzene and its alkyl derivatives (toluene, ethylbenzene, xylenes, styrene, and 1,3,5-trimethylbenzene)—known indicators of human exposure to volatile organic compounds (VOCs) in the air in newly renovated offices at University of Technology (Upper Silesia, Poland). Monthly samples of indoor and outdoor air were collected during the years 2018–2019 by passive methods and analyzed by thermal desorption-gas chromatography with flame ionization detector (TD-GC/FID). In the first month of measurements average concentrations of the sum of five VOCs under consideration was 127.7 µg/m3, then in subsequent months between 15.1 µg/m3 to 87.3 µg/m3. The average concentration of carcinogenic benzene was below 1.5 μg/m3. Toluene had the highest concentration among studied VOCs, accounting for as high as 60% and 84% of the total indoor and outdoor VOCs, respectively. High indoor-to-outdoor (I/O) ratios for ethylbenzene (7.1), m,p-xylene (9.8), and styrene (12.5) indicate the dominant role of indoor sources.

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Nasopharyngeal Carriage of Methicillin-Resistant Staphylococcus aureus (MRSA) among Sickle Cell Disease (SCD) Children in the Pneumococcal Conjugate Vaccine Era

Infectious Disease Reports ◽

10.3390/idr13010022 ◽

2021 ◽

Vol 13 (1) ◽

pp. 191-204

Author(s):

Nicholas T. K. D. Dayie ◽

Deborah N. K. Sekoh ◽

Fleischer C. N. Kotey ◽

Beverly Egyir ◽

Patience B. Tetteh-Quarcoo ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Sickle Cell Disease ◽

Conjugate Vaccine ◽

Sickle Cell ◽

Pneumococcal Conjugate Vaccine ◽

Diffusion Method ◽

Nasopharyngeal Carriage ◽

Cell Disease ◽

Coagulase Negative Staphylococci ◽

Methicillin Resistant

The aim of this cross-sectional study was to investigate Staphylococcus aureus nasopharyngeal carriage epidemiology in relation to other nasopharyngeal bacterial colonizers among sickle cell disease (SCD) children about five years into pneumococcal conjugate vaccine 13 (PCV-13) introduction in Ghana. The study involved bacteriological culture of nasopharyngeal swabs obtained from 202 SCD children recruited from the Princess Marie Louise Children’s Hospital. S. aureus isolates were identified using standard methods and subjected to antimicrobial susceptibility testing using the Kirby-Bauer disc diffusion method. Cefoxitin-resistant S. aureus isolates were screened for carriage of the mecA, pvl, and tsst-1 genes using multiplex polymerase chain reaction. The carriage prevalence of S. aureus was 57.9% (n = 117), and that of methicillin-resistant S. aureus (MRSA) was 3.5% (n = 7). Carriage of the mecA, pvl, and tsst-1 genes were respectively demonstrated in 20.0% (n = 7), 85.7% (n = 30), and 11.4% (n = 4) of the cefoxitin-resistant S. aureus isolates. PCV-13 vaccination (OR = 0.356, p = 0.004) and colonization with coagulase-negative staphylococci (CoNS) (OR = 0.044, p < 0.0001) each protected against S. aureus carriage. However, none of these and other features of the participants emerged as a determinant of MRSA carriage. The following antimicrobial resistance rates were observed in MRSA compared to methicillin-sensitive S. aureus: clindamycin (28.6% vs. 4.3%), erythromycin (42.9% vs. 19.1%), tetracycline (100% vs. 42.6%), teicoplanin (14.3% vs. 2.6%), penicillin (100% vs. 99.1%), amoxiclav (28.6% vs. 3.5%), linezolid (14.3% vs. 0.0%), ciprofloxacin (42.9% vs. 13.9%), and gentamicin (42.9% vs. 13.0%). The proportion of S. aureus isolates that were multidrug resistant was 37.7% (n = 46). It is concluded that S. aureus was the predominant colonizer of the nasopharynx of the SCD children, warranting the continuous monitoring of this risk group for invasive S. aureus infections.

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Mutation-Based Antibiotic Resistance Mechanism in Methicillin-Resistant Staphylococcus aureus Clinical Isolates

Pharmaceuticals ◽

10.3390/ph14050420 ◽

2021 ◽

Vol 14 (5) ◽

pp. 420

Author(s):

Tanveer Ali ◽

Abdul Basit ◽

Asad Mustafa Karim ◽

Jung-Hun Lee ◽

Jeong-Ho Jeon ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Antibiotic Resistance ◽

Active Site ◽

Methicillin Resistant Staphylococcus Aureus ◽

Meca Gene ◽

Resistance Mechanism ◽

Ligand Docking ◽

Clinical Samples ◽

Allosteric Site ◽

Methicillin Resistant

β-Lactam antibiotics target penicillin-binding proteins and inhibit the synthesis of peptidoglycan, a crucial step in cell wall biosynthesis. Staphylococcus aureus acquires resistance against β-lactam antibiotics by producing a penicillin-binding protein 2a (PBP2a), encoded by the mecA gene. PBP2a participates in peptidoglycan biosynthesis and exhibits a poor affinity towards β-lactam antibiotics. The current study was performed to determine the diversity and the role of missense mutations of PBP2a in the antibiotic resistance mechanism. The methicillin-resistant Staphylococcus aureus (MRSA) isolates from clinical samples were identified using phenotypic and genotypic techniques. The highest frequency (60%, 18 out of 30) of MRSA was observed in wound specimens. Sequence variation analysis of the mecA gene showed four amino acid substitutions (i.e., E239K, E239R, G246E, and E447K). The E239R mutation was found to be novel. The protein-ligand docking results showed that the E239R mutation in the allosteric site of PBP2a induces conformational changes in the active site and, thus, hinders its interaction with cefoxitin. Therefore, the present report indicates that mutation in the allosteric site of PBP2a provides a more closed active site conformation than wide-type PBP2a and then causes the high-level resistance to cefoxitin.

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Methicillin-Resistant Staphylococcus aureus Prevalence Among Healthcare Workers in Contact Tracings in a Dutch Hospital

Infection Control and Hospital Epidemiology ◽

10.1017/ice.2020.910 ◽

2020 ◽

Vol 41 (S1) ◽

pp. s316-s317

Author(s):

Veronica Weterings ◽

Heidi Kievits ◽

Miranda van Rijen ◽

Jan Kluytmans

Keyword(s):

Staphylococcus Aureus ◽

The Netherlands ◽

Healthcare Workers ◽

Index Case ◽

Contact Tracing ◽

Secondary Case ◽

National Guidelines ◽

Carriage Rate ◽

Methicillin Resistant ◽

Mlva Type

Background: In The Netherlands, the national guidelines on Methicillin-Resistant Staphylococcus aureus (MRSA) prevention and control advocate screening of healthcare workers (HCWs) after unprotected exposure to MRSA carriers. Although this strategy is largely successful, contact tracing of staff is a time-consuming and costly component. We evaluated our contact tracing policy for HCWs over the years 2010–2018. Methods: A retrospective, observational study was performed in a Dutch teaching hospital. All HCWs who had unprotected contact with an MRSA carrier were included in contact tracing. When there had been a long period of unprotected admission prior to an MRSA finding, or when the index case was an HCW, the entire (nursing) team was tested. All samples of HCWs who were tested for MRSA carriage as part of contact tracing from 2010 until 2018 were included. A pooled nose, throat, and perineum swab was collected using the eSwab medium (Copan) and inoculated on chromID MRSA agar plates (bioMérieux) after enrichment in a broth. Molecular typing was performed using multiple-locus variable number of tandem repeat analysis (MLVA). Results: In total, we included 8,849 samples (range, 677–1,448 samples per year) from 287 contact tracings (range, 26–55 contact tracings per year). Overall, 32 HCWs were colonized with MRSA (0.36%; 95% CI, 0.26%–0.51%). None of them developed a clinical infection. Moreover, 8 HCWs (0.10%; 95% CI, 0.05%–0.19%) were colonized with the same MLVA type as the index case and were detected in 6 of 287 contact tracings (2%). In 4 of 8 of these cases, a positive HCW was the index for undertaking contact tracing. In 3 of 8 cases, it was clear that the HCW who was identified in the contact tracing was the source of the outbreak and was the cause of invasive MRSA infections in patients. Notably, a different MLVA type as the index case was found in 24 HCWs (0.27%; 95% CI, 0.18%–0.40%) of whom 7 of 24 HCWs (29.2%) were intermittent carriers. Conclusions: This study revealed a sustained low MRSA prevalence among samples in contact tracing of HCWs over 9 years. Furthermore, it shows that when MRSA contact tracing is performed according to the national guideline, only 1 of 1,000 samples results in a secondary case. This is similar to the population carriage rate of MRSA in The Netherlands. More frequently, an unrelated strain is found. These findings raise questions regarding the efficacy of the current strategy to perform contact tracing after unprotected exposure.Funding: NoneDisclosures: None

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