MRSA

Introduction: Change point analysis is a technique for detecting change in trend over time. Segmented regression analysis and joinpoint analysis are used to try to determine the most important interventions which impact rates of healthcare associated infections (HAIs). AiMs: Use change point analysis to determine which interventions reduce rates of HAIs. Data and Methods: The data on HAIs was monitored by Health Protection Scotland (HPS) and includes staphylococcus aureus bacteraemia (SAB) and clostridium difficile infection (CDI). Since 2004, several interventions were implemented by NHS to reduce the rates and these were reported by Health Protection Scotland (HPS). Segmented regression and joinpoint models are investigated and developed to detect times when the indection rates changed significantly. Profile likelihood and bootstrapping are used to construct confidence intervals for the joinpoints. Results: Interventions which took place from was a significant change in the trend of MRSA bacteraemia. The trend of MSSA bacteraemia did change significantly from January-March 2011, however, joinpoint analysis did not indicate any change in MSSA bacteraemia. A segmented model suggested interventions around October-December 2009 had an impact on the rates of CDI in patients over 65 years and joinpoint analysis showed from April-June 2008 and January-March 2011 the rates changed. Conclusion: Segmented regression analysis detects changes in rates associated with specific interventions. It appears from this that training of hospital staff in dealing with infection outbreaks and the implementation of an antibiotic policy are associated with an observed reduction in the rates of SAB and CDI in healthcare settings. Joinpoint analysis gives the most robust modelling to estimate significant change. Keywords: Segmented regression; joinpoint analysis; seasonal effect; bootstrap confidence interval; profile likelihood confidence interval; healthcare associated infections; MRSA; MSSA; CDI. I. INTRODUCTION Everything in the world tends to change over time such as the economy, education and epidemiology. It is of interest to know when changes happened to determine the cause. Change point analysis aims to detect a time point when a trend in data changes. A trend in data may have multiple change points. The change point analysis addresses two aspects in the analysis of a trend-a hypothesis testing approach to decide if there are any change points and an estimation approach to locate the change. Detecting change points was investigated using different methods. Segmented regression analysis was used to discover change points where the rates change significantly after a specific intervention and thereby help improve the quality of the interventions [Wagner et al. (2002)]. Joinpoint analysis was used to identify change points at unknown times and to estimate the location of them. Using a joinpoint statistical software package [NCISR (2020)] the simplest joinpoint model (which in includes only a time variable) is fitted to the data. The minimum and maximum number of joinpoints is determined. The program starts with the minimum number of joinpoints and tests whether additional joinpoints are statistically significant using a permutation method. These are added to the model up to the maximum number. A grid search method has a discrete number of locations that are tested to find the best fitted model and joinpoints occur exactly at one or more of these locations (observed rate) [Kim (2001)].

The effect of fermented palm wine tapped from Raphia palm tree (Raphia hookeri) on the growth of some common diarrhoeagenic bacteria such as Staphylococcus aureus, Escherichia coli, Salmonella typhi, Shigella dysentariae and Esherichia coli 0157:H7 was carried out using agar diffusion method. The palm wine used had growth inhibitory effect on all the test organisms with diameter of zones of inhibition ranging from 2.20mm to 28.20mm. Palm wine subjected to fermentation for 168hours (7 days) exerted the highest growth inhibitory effect on all the test bacteria. The inhibition mediated by this palm wine was superior to that of some conventional antibiotics used such as tetracycline, ampiclox and ampicillin. It is conceivable therefore that palm wine subjected to natural fermentation or freshly tapped could be used to treat diarrhoea caused by these organisms.

Methicillin-resistant Staphylococcus aureus (MRSA) is a modern plague of growing proportions. Herbal medicine offers two potential solutions to this major health issue. First, in some cases, herbs may be substituted for antibiotics altogether. This approach reduces antibiotic use and thus helps prevent worsening of antibiotic resistance, while still controlling the MRSA. Second, herbs can augment the effect of antibiotics and even overcome drug resistance when antibiotics are appropriate and necessary. This article discusses herbs that potentially have these benefits: The herbs include Camellia sinensis (green tea) leaf, Theobroma cacao (chocolate) fruit, Melaleuca alternifolia (tea tree) leaf essential oil, Pelargonium sidoides (African geranium) essential oil, Cymbopogon flexuosus (lemongrass) essential oil, Thymus capitatus (thyme) flowering top essential oil, Lavandula spp. (lavender) essential oil, Panax ginseng (Asian ginseng) root, Panax quinquefolius (American ginseng) root, Geranium caespitosum (pineywoods geranium) herb, Rosmarinus officinalis (rosemary) leaf and essential oil, Lycopus europaeus (bugle weed) herb, Santalum spicatum (Australian sandalwood), Origanum vulgare (oregano) herb essential oil, Allium sativum (garlic) bulb, Mahonia aquifolium (Oregon grape) root, Hypericum perforatum (St. John's wort) herb, Bursera microphylla (elephant tree) resin, Commiphora molmol (myrrh) resin, Cinnamomum zeylanicum (true cinnamon) bark volatile oil, Echinacea angustifolia (echinacea) root, Quercus spp. (oak) bark, Anemopsis californica (yerba mansa) root, Usnea spp. (old man's beard) thallus, Juniperus communis (juniper) fruit, Larrea tridentata (chaparral) herb, Glycyrrhiza glabra (licorice) root, Zingiber officinale (ginger) rhizome, and Syzygium aromaticum (clove) volatile oil.

Antibiotic susceptibility study of bacteria isolates, in particular Staphylococcus and MRSA, were conducted using standard procedure from the samples obtained from hospital settings. The prevalence of MRSA strains were 3.28%. These isolated MRSA strains were resistant to ampicillin (100%) but sensitive against vancomycin, clindamycin and chloramphenicol (100%) with variable zone of inhibition against different other antibiotics. Nosocomial infection has become global health burden with increased morbidity and mortality. Emerging antibiotic resistance has resulted in a significant healthcare expenditure. Therefore necessary steps are warranted to stop the emergence of these resistant strains and provide health education for effective prevention and control of nosocomial infections.

Urinary tract infections (UTIs) are amongst the most common infections encountered in clinical practice with an estimated 150 million UTIs per annum worldwide. The introduction of antimicrobial therapy has contributed significantly to the management of UTIs. However the main problem with current antibiotic therapies is the rapid emergence of antimicrobial resistance in hospitals and the community. Aims: To determine the frequency and pattern of antibiotic resistance among uropathogens in a Tertiary Care Hospital in Silchar. Settings and Design: Outdoor and indoor wards of Silchar Medical College & Hospital, Silchar/ Retrospective study Methods and Material: An analysis was done on all the urine samples (1799) sent for culture and sensitivity to the department of Microbiology, SMCH, Silchar from 1 st January 2011 to 31 st December 2013. A total of 659 positive urinary isolates were detected from the 1799 samples. Antibiotic susceptibility was done on Mueller Hinton Agar plate by Bauer-Kirby method. Extended spectrum beta lactamase (ESBL) production was determined by the double disk approximation test and the Clinical and Laboratory Standards Institute (formerly NCCLS) confirmatory method and Methicilin Resistant Staphylococcus aureus (MRSA) production was determined by the oxacillin disc inhibition test and the Clinical and Laboratory Standards Institute (formerly NCCLS) confirmatory method. Statistical analysis used: Microsoft excel sheet was used to plot the data and prepare the graphs. Results: During the study period, 1799 consecutive urine samples were processed from OPD and indoor patients, 659 (36.63%) of these urine samples [OPD-106 (16.08%) and Indoor-553 (83.92%)] yielded significant growth of pathogens. Escherichia coli was the most frequently isolated uropathogen accounting for 38.54% of the total isolates. ESBL production was observed in 28.74% of E. coli strains and 40.74% of Klebsiella strains. MRSA producing organisms was found to be 28.40% of S. aureus strains. With the exception of nitrofurantoin and amoxycillin/clavulinic acid for gram negative bacteria and linezolid for gram positive cocci, resistance to agents commonly used as oral treatments for UTI was quite high. Conclusions: The study revealed E. coli as the predominant bacterial pathogen, followed by S. aureus for UTIs in Silchar Medical College & Hospital, Silchar, Assam. An increasing trend in the production ESBLs and MRSAs among UTI pathogens were noted.

Out of 130 clinical samples, a total of 37 (28.4%) Staphylococcus aureus isolates were recovered, from skin samples, ear, blood and throat, and both urine and vagina as (75.6), (8.1%), (5.4%), and (10.8%), respectively. Results showed that 21 (56.7%) isolates were identified as β-lactam resistant. The susceptibility to 25 antibiotics were tested using disc diffusion test resulting in 80% of 21 bacterial isolates were resistant to 22 antibiotics but they were sensitive to teicoplanin, netilmicin and chloramphenicol. For detection of Borderline oxacillin resistance S.aureus (BORSA), all of 21 isolates were tested by using oxacillin disc (1mcg). Results showed that all 21 isolates were resistant to oxacillin and identified as MRSA as they were resistant to both oxacillin and cefoxitin. Two–fold agar dilution susceptibility method to oxacillin and vancomycin were performed for 21 isolates. All 21 isolates showed resistance to oxacillin, and 16 (%76) were sensitive to vancomycin while 5 (%24) decreased susceptibility to vancomycin (VISA). All 21 isolates had mecA gene and identified as MRSA and no BORSA detected in this study which lack mecA gene.

Cephalosporins are beta-lactam antibiotics classified into five generations. The newest generation has three representatives: ceftaroline fosamile, the combination ceftolozane/tazobactam (cephalosporin/beta-lactamase inhibitor), and ceftobi-prole medocaril. These new cephalosporins are valuable anti-infective agents, with potent activity against multidrug-resistant bacteria, and with a positive balance between benefits and side effects. However, the fifth-generation cephalosporins should be judiciously used to prevent the occurrence of bacterial resistance phenomenon.

Tanaman singawalang (Petiveria alliaceae) secara tradisional di Indonesia digunakan sebagai analgetik, anti inflamasi dan obat untuk batuk darah. Obat tradisional yang mengandung Petiveria alliacea telah digunakan di Karibia, Amerika Latin, Afrika Barat dan daerah lainnya selama ratusan tahun untuk mengobati rasa sakit, flu, inflamasi, tumor, infeksi bakteri, jamur, hiperlipidemia, diabetes dan penyakit lainnya. Penelitian ini bertujuan mengetahui aktivitas singawalang yang tumbuh di Indonesia terhadap bakteri yang resisten dan peka terhadap antibiotik. Pengujian dilakukan dengan menentukan konsetrasi hambat minimum (KHM) dan konsentrasi bakterisidal minimum dengan metode broth microdilution dan kajian tipe kerja dengan melihat kurva pertumbuhan. Daun singawalang diperoleh dari daerah Cilende Bogor. Pengujian aktivitas dilakukan terhadap daun kering, daun segar, batang segar dan akar segar yang diekstraksi secara maserasi dan daun kering secara refluks menggunakan etanol. Ektrak etanol daun kering menunjukkan aktivitas penghambatan terhadap sepuluh bakteri yaitu MSCNS (Methicillin-Susceptible Coagulase-Negative Staphylococcus ), Pseudomonas aeruginosa, Bacillus subtilis, B.cereus, Staphylocoocus aureus, MRSA (Methicillin-Resistant Staphylococcus aureus), Escherichia coli, MRCNS (Methicillin-Resistant Coagulase-Negative Staphylococcus), MSSA (Methicillin-Susceptible Staphylococcus aureus), dam VRE (Vancomycin-Resistant Enterococcus ) dengan nilai KHM berturut turut 256, 16, 32, 64,16,16, 32,16, 128, dan 256 µg/ml dan aktivitas antibakteria ektrak etanol daun segar pada bakteri yang sama dengan nilai KHM berturut turut 512, 64, 64, 512, 64, 256, 32, 256, 512, dan 512µg/ml. Hasil penentuan dengan kurva pertumbuhan bakteri menunjukkan bahwa ekstrak etanol daun kering dengan maserasi bersifat bakteriostatik terhadap MRSA, VRE dan MRCNS sampai konsentrasi 8 KHM.

Context: Essential oils represent a therapeutic alternative in natural products against pathogenic bacteria that have become resistant to antibiotics and threaten public health and individual health of patients.

Aims: To determine the antimicrobial activity of two essential oils of different densities, obtained by hydrodistillation of Pimenta racemosa var. racemosa fresh leaves collected from Táchira, Venezuela against different multirresistant bacterial strains of nosocomial origin.

Methods: Disc diffusion agar method was carried out against seven reference strains: Candida albicans (CDC-B385), Candida krusei (ATCC 6258), Enterococcus faecalis (ATCC 29212), Escherichia coli (ATCC 25922), Klebsiella pneumoniae (ATCC 23357), Pseudomonas aeruginosa (ATCC 27853), Staphylococcus aureus (ATCC 25923) and three different bacterial strains of nosocomial origin: Methicillin-resistant Staphylococcus aureus (MRSA), extended-spectrum β-lactamase (ESBL) producing Escherichia coli and Enterobacter cloacae.

Results: The essential oils of Pimenta racemosa var. racemosa inhibited the development of all microorganisms tested with minimum inhibitory concentration (MIC) values ranging from 20 to 400 μL/mL.

Conclusions: This is the first report concerning antimicrobial activity of essential oils obtained from Pimenta racemosa var. racemosa collected from Táchira, Venezuela with different densities. Furthermore, results showed the essential oils of this species might be an alternative as antimicrobial agent for the pharmaceutical industry.

The emergence of methicillin-resistant Staphylococcus aureus (MRSA) infection has increased precipitously over the past several decades, with far-reaching health care and societal costs. MRSA infections in the context of burn wounds lead to invasive disease that could potentially cause mortality. Chloramphenicol is a well-known broad-spectrum bacteriostatic antibiotic that has been used since 1949, but due to its hydrophobicity, poor penetration in skin, fast degradation, and toxicity, its application has been hindered. Furthermore, it has been demonstrated that old antibiotics such as chloramphenicol remained active against a large number of currently prevalent resistant bacterial isolates due to their low-level use in the past. Recently, the novel nanoparticulate drug-delivery system has been used and reported to be exceptionally useful for topical therapeutics, due to its distinctive physical characteristics such as a high surface-to-volume ratio and minuscule size. It helps to achieve better hydrophilicity, bioavailability, and controlled delivery with enhanced therapeutic index, which has resulted in decreased toxicity levels compared to the crude drug. Here, we report a novel chloramphenicol loaded with poly(ε-caprolactone) (PCL)-pluronic composite nanoparticles (CAM-PCL-P NPs), physicochemical characterizations, and its bioactivity evaluation in a MRSA-infected burn-wound animal model. CAM-PCL-P NPs could encapsulate 98.3% of the drug in the nanoparticles and release 81% of the encapsulated drug over 36 days with a time to 50% drug release of
72 hours (51%). Nanoparticle suspensions maintained the initial properties with respect to size and encapsulation efficiency, even after 6 months of storage at 4°C and 25°C, respectively (P0.05). Significant reduction in the level of toxicity was observed for CAM-PCL-P NPs compared with that of free drug as confirmed from hemolytic activity against human blood erythrocytes and cytotoxicity assay against an MCF-7 breast cancer cell line. In vitro antibacterial activities were performed by zone of inhibition, minimum inhibitory concentrations, minimum bacterial concentration, and time-kill assays, which showed that CAM-PCL-P NPs exhibited significantly enhanced anti-MRSA activity against ten clinical isolates of MRSA strains. The augmented activity of CAM-PCL-P NPs was further tested on a MRSA-infected burn-wound animal model and achieved quicker efficacy in MRSA clearance and improved the survival rate compared with free-chloramphenicol treatment. Thus, we propose CAM-PCL-P NPs as a promising novel antimicrobial candidate that may have a good potential for preclinical applications.
Keywords: chloramphenicol, PCL-pluronic, nanoparticle, methicillin-resistant Staphylococcus aureus, anti-MRSA activity, burn-wound animal model

Antibiotic resistance and biofilm-forming capacity contribute to the success of Staphylococcus aureus as a human pathogen in both healthcare and community settings. These virulence factors do not function independently of each other and the biofilm phenotype expressed by clinical isolates of S. aureus is influenced by acquisition of the methicillin resistance gene mecA. Methicillin-sensitive S. aureus (MSSA) strains commonly produce an icaADBC operon-encoded polysaccharide intercellular adhesin (PIA)-dependent biofilm. In contrast, the release of extracellular DNA (eDNA) and cell surface expression of a number of sortase-anchored proteins, and the major autolysin have been implicated in the biofilm phenotype of methicillin-resistant S. aureus (MRSA) isolates. Expression of high level methicillin resistance in a laboratory MSSA strain resulted in (i) repression of PIA-mediated biofilm production, (ii) down-regulation of the accessory gene regulator (Agr) system, and (iii) attenuation of virulence in murine sepsis and device
infection models. Here we review the mechanisms of MSSA and MRSA biofilm production and the relationships between antibiotic resistance, biofilm and virulence gene regulation
in S. aureus

Introduction: Methicillin resistant Staphylococcus aureus (MRSA) is a multidrug resistant organism that threatens the continued effectiveness of antibiotics worldwide and causes a threat almost exclusively in hospitals and long-term care settings. This study investigated the prevalence of MRSA strains and their sensitivity patterns against various antibiotics used for treating hospitalized patients in a major tertiary surgical hospital in Benghazi, Libya.
Methodology: We investigated 200 non-duplicate S. aureus strains isolated from different clinical specimens submitted to the Microbiology Laboratory at Aljala Surgical and Trauma Hospital, Benghazi, Libya from April to July 2007. Isolates were tested for methicillin resistance by the oxacillin disc-diffusion assay according to Clinical and Laboratory Standards Institute guidelines. MRSA strains were tested for antimicrobial resistance (i.e., vancomycin, ciprofloxacin, erythromycin, chloramphenicol and fusidic acid) using commercial discs. Information on patient demographics and clinical disease was also collected.
Results: Of the isolates examined 31% (62/200) were MRSA. No significant differences were observed in the prevalence of MRSA among S. aureus from females or males or from different age groups. Most MRSA were isolated from burns and surgical wound infections. Antibiotic resistance patterns of 62 patients with MRSA to vancomycin, ciprofloxacin, fusidic acid, chloramphenicol and erythromycin were 17.7%, 33.9%, 41.9%, 38.7% and 46.8% of cases, respectively.
Conclusion: MRSA prevalence in our hospital was high and this may be the case for other hospitals in Libya. A sound surveillance program of nosocomial infections is urgently needed to reduce the incidence of infections due to MRSA and other antimicrobial-resistant pathogens in Libyan hospitals.

Aim: This study aimed to investigate the antibacterial efficacy of eight commercially available essential oil (EO) blends and characterize the effect on the expression of some virulence genes against methicillin-resistant Staphylococcus aureus (MRSA). Materials and Methods: In vitro evaluation of the antimicrobial effects of oils against MRSA was performed using the disk diffusion method and by measuring the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC). The EOs (A-F) were contained (β-pinene, carvacrol, carvone, dimethyl trisulfide, linalool, limonene, menthol, monoterpene hydrocarbons, and thymol) in different amounts. In addition, a real-time polymerase chain reaction was also used to determine the gene expression of the virulence genes (intercellular adhesion cluster [ica]-9, ica-15, and RNA III) against MRSA (ATCC 43300) after treatment with selected oils. Results: Among the eight EOs evaluated, EO (D), (E), and (A) showed, in general, ...

Introduction: There are various virulence factors encoded by Staphylococcus Aureus, which enable them to cause nosocomial infections and mastitis in dairy cattle. The clf-A gene mediates the bacterial colonization through binding to the extracellular matrix of the host. Treatment of such infections becomes more difficult due to increased resistance to methicillin. The current study aimed at investigating the frequency of clf-A, mec-A, and mec-C genes in S. Aureus strains isolated from hospital infections and cow’s milk.
Methods: A total of 280 clinical samples as well as 100 milk samples from cattle with mastitis were collected. After identification of isolates, methicillin-resistant strains were identifies using agar screening and the cefoxitin disc diffusion test. In addition, the Minimum Inhibitory Concentration (MIC) value of oxacillin was determined using the E-test method. Polymerase Chain Reaction (PCR) was used to detect clf-A, mec-A, and mec-C genes in the methicillin-resistant isolates. Out of 120 S. Aureus strains isolated from nosocomial infections, 40 were identified as Methicillin-Resistant Staphylococcus Aureus (MRSA), while only 1 isolate from cow’s milk was MRSA.
Results: Out of the 280 studied isolates, 35 clinical strains (87.5%) carried mec-A gene, and the frequency of clf-A gene was 80% and 100% in clinical and bovine milk samples, respectively. Importantly, MRSA strains harbouring clf-A gene, isolated from wound samples, exhibited the highest frequency. The mec-C gene was not found in clinical and milk isolated strains. The high frequency of clf-A gene in MRSA strains isolated from wound indicated a probable role of this virulence factor in skin colonization, as well as distribution and spread of the strains.
Conclusion: Development of an appropriate method seems to be particularly useful for preventing the distribution of such strains.

The methanolic extract of the leaves of Smilax lanceifolia Roxb. (Family-Smilacaceae) was subjected to pharmacological investigation to ascertain analgesic and antibacterial activity.. The phytochemical screening demonstrated the presence of different types compound like anthraquinone glycoside, alkaloids, terpenoids, tannins, carbohydrate,flavone aglycone, saponin, phenolic compound, reducing sugar, and phlobotannin. The methanolic extract of the plant was tested for analgesic activity using chemical writhing method (0.6% acetic acid) and antibacterial activity against Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, Pseudomonas aeruginosa and Salmonella typhi bacteria using cup diffusion method. The extract significantly(p<0.05) inhibited in a dose dependent fashion analgesia(nociception) induced by acetic acid as indicated by the reduction in number of writhing movement in mice. Antibacterial activity was observed against S.aureus, S.typhi, E.faecalis, and E.coli in dose dependent manner.

Background and Aim: The coronavirus disease-19 (COVID-19) pandemic caused global economic and health problems. The pandemic increased the number of infectious diseases categorized as neglected diseases, such as staphylococcosis, which is caused by methicillin-resistant Staphylococcus aureus (MRSA). Celery is an herb that consist of antioxidants that can potentially act as antimicrobial agents. This study aimed to analyze the efficacy of celery alcoholic extract against systemic MRSA infections in rat models.

Materials and Methods: In this study, 36 male, 6-month-old Sprague-Dawley rats (average weight: 300 g) were used as models. The rats were divided into six groups: Group K– (negative control), Group K+ (infected with MRSA without therapy), Group V (infected with MRSA+100 mg vancomycin per kg body weight [BW]), Group P1 (infected with MRSA+1 mg celery extract per kg BW), Group P2 (infected with MRSA+2 mg celery extract per kg BW), and Group P4 (infected with MRSA+4 mg celery extract per kg BW). The therapy was given once daily for 7 days. Blood and organs were taken on day 7 for hematology, serology, immunohistochemistry, and histopathology.

Results: Results showed that 4 mg celery extract per kg BW promotes the healing of MRSA systemic infections in rat models (p≤0.05). The better prognosis was indicated by the normalization of red blood cell indices, white blood cell, neutrophil and lymphocyte counts, Cluster of differentiation 4+, Cluster of differentiation 8+, and Cyclooxygenase-2 expression and absence of severe tissue damage. Celery extracts inhibited MRSA growth in the blood samples.

Conclusion: It can be concluded that celery alcoholic extract can potentially be used as an antimicrobial agent against systemic MRSA infections. A clinical study regarding the efficacy of celery extract must be conducted to ensure its potency against MRSA infections in humans.

Background and Aim: Extended-spectrum β-lactamases (ESBL) in Escherichia coli constitutes one of the major threats to modern medicine, and the increasing pollution with quaternary ammonium compounds (QACs) has been suspected to contribute to the spread of ESBL-producing bacteria. The aim of the study was to investigate ESBLA and ESBLM-C-producing E. coli isolates for their coresistance to QACs and their phylogeny isolated from a Swedish University Hospital.

Materials and Methods: Coresistance in E. coli with production of ESBL enzymes of the type blaCTX-M (n=23) was compared to E. coli producing AmpC type ESBL enzymes blaCMY and blaDHA (n=27). All isolates were tested for susceptibility to antibiotics and QACs, and high-quality whole-genome sequences were analyzed for resistance determinants.

Results: The plasmid-borne small multidrug resistance (SMR) efflux pump sugE(p) was solely present in blaCMY-producing E. coli (n=9), within the same genetic environment blaCMY–blc–sugE(p). Other small multidrug efflux pumps were found without association for ESBL-types: emrE (n=5) and the truncated qacEΔ1 (n=18).

Conclusion: Coresistance of ESBL enzymes and SMR efflux pumps in E. coli was common and might indicate that other substances than antibiotics contribute to the spread and emergence of antibiotic resistance.

Background and Aim: Methicillin-resistant Staphylococcus aureus (MRSA) is one of the most recognized "superbugs" and a common cause of community-associated and nosocomial infections; furthermore, when chicken meat is considered a good growth medium for S. aureus to make a plausible vehicle to propagate MRSA, then this study was conducted to evaluate the efficiency of ozonated water (0.5 ppm) in the elimination or reduction of MRSA contaminating fresh and frozen chicken meat sold in local markets in the Wasit Province.

Materials and Methods: A total of 72 samples of fresh and frozen chicken meat were randomly collected from dissimilar native markets: Fresh chicken meat (n=32) and frozen chicken meat (n=40). Isolation and identification of MRSA isolates were conducted using standard bacteriological, biochemical, RapID™ Staph Plus System (Remel, R8311009), and latex agglutination tests such as Dry SPOT Staphytect Plus (Oxoid, DR0100M) and PBP2' Test Kit (Oxoid, DR0900A). The generation of ozone (O3) was carried out using O3 generator (A2Z/AQUA-6, USA), and its concentration (ppm) in water was determined using CHE-Mets®-Kit, USA.

Results: A total of 39 (54.2%) of 72 fresh and frozen chicken meat were positive for S. aureus; of those 39 positive samples, 13 (33.3%) were identified as MRSA. The antibiotic sensitivity test results revealed that all MRSA isolates had multiple resistance to at least four antimicrobial agents for which these isolates had 12 antibiotic resistance patterns. Results of O3 treatment in MRSA isolate contaminating 13 of both fresh and frozen chicken meat samples showed that, after treatment with ozonated water (0.5 ppm/4°C), the overall negative samples were 23.1% and 69.2% for 30 and 45 min, respectively. The decrease in the percentage of positive samples was very significant from a public health perspective. Furthermore, the antimicrobial efficacy of ozonated water (0.5 ppm) on the reduction of the MRSA count (log10 colony-forming units [CFU]/ml) was assessed in four positive samples of fresh and frozen chicken meat, and the results revealed that, after treatments, the overall reduction was 2-4 log10 (CFU/ml) after 45 min. This reduction is highly significant from a public health perspective.

Conclusion: From the data obtained from this study, it can be concluded that fresh and frozen chicken meat sold in the different markets of Wasit Province was highly contaminated by S. aureus during the study period with a total prevalence of 54.2%; among those, 33.3% were recognized as MRSA. Under the conditions described in the present study, O3 at the concentration of 0.5 ppm is highly effective in reducing the number of MRSA-positive samples and the number decreased with increased exposure time to ozonated water at the same concentration. These findings indicated that O3 treatment might constitute the basis for an alternative method to reduce meat contamination with foodborne pathogens such as MRSA.

The difficulty in successfully treating infections caused by methicillin-resistant Staphylococcus aureus (MRSA) has led to them being referred to as highly virulent or pathogenic. In our study of one of the major healthcare-associated MRSA (HA-MRSA) clones, we show that expression of the gene responsible for conferring methicillin resistance (mecA) is also directly responsible for reducing the ability of HA-MRSA to secrete cytolytic toxins. We show that resistance to methicillin induces changes in the cell wall, which affects the bacteria's agr quorum sensing system. This leads to reduced toxin expression and, as a consequence, reduced virulence in a murine model of sepsis. This diminished capacity to cause infection may explain the inability of HA-MRSA to move into the community and help us understand the recent emergence of community-associated MRSA (CA-MRSA). CA-MRSA typically express less penicillin-binding protein 2a (encoded by mecA), allowing them to maintain full virulence and succeed in the community environment.

Pork producers selected from the National Pork Board`s producer database were surveyed. Five (3.7%) reported being diagnosed with a MRSA infection. Risk factors related to swine farm biosecurity were examined. None were statistically significant predictors of MRSA infection.

Methicillin Resistant Staphylococcus aureus (MRSA) has emerged as a major hospital pathogen. However studies from India between 1994-2001, reported the incidence of MRSA between 32.8%-51.6%. In recent years, there have been several reports of community-associated MRSA (CA-MRSA) infections throughout the world. The present study was aimed at the epidemiological survey of methicillin resistant S. aureus in the community and hospital. Samples were collected from hospital (202 samples from staff and patients, 50 samples from operation theatres and ICU) and environmental groups (Swabs from nose and axilla were collected from 70 children and 56 adults). The samples were tested for the presence MRSA. Staphylococci was isolated from 55 (30 from children and 25 from adults) samples from community group where as in 37 samples collected from the various groups of people in the hospital and none from the environment i.e. operation theater and ICU. The S. aureus isolates were studied for methicillin resistance by testing the sensitivity of the isolate to Oxacillin. Of the 26 isolates tested of S. aureus from the community (11 from children and 15 from adults), no MRSA was found. In the hospital, out of the 15 S. aureus isolates, five (33.3%) were confirmed as MRSA. Thus this study shows a prevalence of 33.3% of MRSA in hospital specimens collected from patients, and no carrier state among hospital staff or in the environments. The specimen collected from the community did not show any MRSA. It is possible that CA-MRSA has not yet established in the community studied in the present work at the present time. Further surveillance studies are necessary to continuously monitor the presence of CA-MRSA to alert the clinicians to prevent the serious complications.

Methicillin resistant Staphylococcus aureus (MRSA) is a major human pathogen associated with nosocomial and community infections. Panton Valentine leukocidin (PVL) is considered one of the important virulence factors of S. aureus responsible for destruction of white blood cells, necrosis and apoptosis and as a marker of community acquired MRSA. This study was aimed to determine the prevalence of PVL genes among MRSA isolates and to check the reliability of PVL as marker of community acquired MRSA isolates from Western Nepal. A total of 400 strains of S. aureus were collected from clinical specimens and various units (Operation Theater, Intensive Care Units) of the hospital and 139 of these had been confirmed as MRSA by previous study. Multiplex PCR was used to detect mecA and PVL genes. Clinical data as well as antimicrobial susceptibility data was analyzed and compared among PVL positive and negative MRSA isolates. Out of 139 MRSA isolates, 79 (56.8 %) were PVL positive. The majori...

Background: Staphylococcus aureus is one of the most important food-borne pathogens. The objective of this study was to determine the prevalence, molecular types and drug resistance pattern of S. aureus isolated from retail meat in Tabriz city.

Background and Aim: One of the complications of diabetes mellitus is diabetic ulcer. Diabetic ulcer is commonly infected by infectious agents, especially methicillin-resistant Staphylococcus aureus (MRSA). This study aimed to evaluate the potential effects of alcoholic extracts of Aloe vera, Apium graveolens, and Sauropus androgynus on promoting wound healing in a diabetic wound infected with MRSA.

Materials and Methods: A total of 60 male Sprague-Dawley rats (6 months old, weighing 250-300 g) were injected with 65 mg/kg body weight of streptozotocin to induce diabetes. On day 7, the backs of the rats were shaved, and two circular wounds (4 mm in diameter) were created on their back, which were infected with MRSA. The rats were divided into six groups: Group I = control, Group II = treated with cream base without extract, Group III = treated with 2% A. vera cream, Group IV = treated with 2% A. graveolens cream, Group V = treated with 2% S. androgynus cream, and Group VI = treated with 2% A. vera + 2% A. graveolens + 2% S. androgynus cream. The wounds were treated twice a day for 14 days. The data were collected on days 7 and 14.

Results: The results showed that all three herbal extracts and their combination decreased wound area and percentage of the wound, increased tensile strength of skin, collagen deposition, vascular endothelial growth factor expression, and skin thickness, and depressed the C-reactive protein profile and cyclooxygenase-2 expression.

Conclusion: A. vera, A. graveolens, and S. androgynus creams can be used as herbal therapies against diabetic wounds infected with MRSA, both as a single and combination treatment.

"Staphylococcus aureus is major human pathogen causing large variety of infections worldwide. This study carried out to isolate S. aureus from different clinical cases, also detection of MRSA prevalence and VRSA emergence, in addition to shedding light on strains that have to be multidrug resistance against various antibiotics. The clinical samples were collected from Al-Jumhuory Teaching Hospital patients in Mosul, isolates identification were achieved by conventional procedures including biochemical and physiological tests, and the specific latex agglutination test. The sensitivity pattern achieved by using disk diffusion technique, for MRSA and VRSA detection oxacillin-disk (1 μg) and vancomycin-disk (30 μg) were used respectively. Results revealed, among 17 S. aureus isolates, 7 (41%) were mostly isolated from patients with wound and burn infections. Isolates had high resistance rate against ampicillin (100%) and cefotaxime (81%), and lower resistance rate against several antibiotics. MRSA was 88% of total isolates, 93.3% of MRSA were multidrug resistance to 3-9 of antibiotics. Six isolates (40%) of MRSA were VRSA. It is concluded that antibiotics other than vancomycin can be used as anti-MRSA agents after a sensitivity test to prevent the prevalence of VRSA, the major cause of this chemotherapy problems maybe irrational and indiscriminate use of broad-spectrum antibiotics."

Özet Amaç: Bu araştırmanın amacı Bastar bölgedeki yaygınlığını ve S. aureus antibiyotik direncini etüd edilerek. Gereç ve Yöntem: Ocak 2010-Mayıs 2012 tarihinden itibaren, 916 S. aureus izolatı kültüre klinik örneklerden standart testlerle tespit edilmiştir. MRSA tespit oksasilin ekran ağar tarafından yapılan ve sefoksitin disk difüzyon testleri yapıldı. Kirby-Bauer disk difüzyon testi antibiyotik duyarlılık incelemek için kullanılmıştır. Vankomisin MIC ve linezolid Etest tarafından incelendi. Bulgular: Izolatların % 34.8 MRSA idi. MRSA izolatları içinde,% 63 (165) eritromisine dirençli bulunmuştur, azitromisine % 39.3 (103), klindamisin için % 61.8 (162), % 81.5 (260) kotrimoksazol için, % 0.6 (2) linezolide, % 0.9 (3) vankomisine, % 76.5 (244) tetrasiklin, % 67.7 (216) gentamisin için % 63.3 (202) siprofloksasin, % 8.5 (27) gatifloksasin için, % 16.4 (43), kloramfenikol % 68.4 (39 ) norfloksasin nitrofurantoine % 12.3 (7), Sulfısoxazol için % 80.7 (46) ve % 80.7 (46) antibiyotik trimetoprim için. Tartışma: Çalışması bu bölgeden ilk kez yapıldı. Prevalans ve ilaç direnci oranı diğer çalışmalar ile karşılaştırılmıştır. Linezolid direncinin ortaya çıkması ve MRSA izolatlarının görece yüksek vankomisin direnci bu çalışmanın endişe verici bir bulgudur. Kotrimoksazol ve/veya gentamisin ilk ampirik tedavisi olarak kabul edilebilir, ancak Antibiyograma göre doğru bir antibiyotik ile hemen değiştirilmelidir. Abstract Aim: The aim of this research was to study the prevalence and antibiotic resistance of S. aureus in the Bastar region. Material and Method: From the clinical samples cultured from Jan 2010 to May 2012, 916 S. aureus isolates were identified by the standard tests. Screening of MRSA was done by oxacillin screen agar and cefoxitin disk diffusion tests. Antibiotic susceptibility was examined by Kirby-Bauer disk diffusion test. For MIC of vancomycin and linezolid, Etest was performed. Result: Of the isolates, 34.8% were MRSA. In the MRSA isolates, 63% (165) were found resistant to erythromycin, 39.3% (103) to azithromycin, 61.8% (162) to clindamycin, 81.5% (260) to cotrimoxazole, 0.6% (2) to linezolid, 0.9% (3) to vancomycin, 76.5% (244) to tetracycline, 67.7% (216) to gentamycin, 63.3% (202) to ciprofloxacin, 8.5% (27) to gatifloxacin, 16.4% to chloramphenicol, 68.4% (39) to norfloxacin, 12.3% (7) to nitrofurantoin, 80.7% (46) to sulfisoxazole, and 80.7% (46) to trimethoprim antibiotics. Discussion: The study was conducted first time from this region. The prevalence and drug resistance percentage is compared with other studies. Emergence of linezolid resistance and relatively higher vancomycin resistance in the MRSA isolates is a worrisome finding of this study. Cotrimoxazole and/or gentamycin may be considered as initial empiric treatment, but must be replaced immediately with the correct antibiotic according to the antibiogram.

This study aimed to characterize Staphylococcus aureus (S. aureus) strains isolated from human infections in Mongolia. Infection samples were collected at two time periods (2007-08 and 2011) by the National Center for Communicable Diseases (NCCD) in Ulaanbaatar, Mongolia. S. aureus isolates were characterized using polymerase chain reaction (PCR) for mecA, PVL, and sasX genes and tested for agr functionality. All isolates were also spa typed. A subset of isolates selected by frequency of spa types was subjected to antimicrobial susceptibility testing and multilocus sequence typing. Among 251 S. aureus isolates, genotyping demonstrated methicillin resistance in 8.8% of isolates (22/251). Approximately 28% of the tested S. aureus isolates were observed to be multidrug resistant (MDR). Sequence type (ST) 154 (spa t667) was observed to be a strain with high virulence potential, as all isolates for this spa type were positive for PVL, had a functional agr system and 78% were MDR. S. aureus isolates of ST239 (spa t037) were observed to cause infections and roughly 60% had functional agr system with a greater proportion being MDR. Additionally, new multilocus sequence types and new spa types were identified, warranting continued surveillance for S. aureus in this region.

Staphylococcal food-borne disease (SFD) is one of the most common food-borne diseases worldwide resulting from the contamination of food by preformed S. aureus enterotoxins. It is one of the most common causes of reported food-borne diseases in the United States. Although several Staphylococcal enterotoxins (SEs) have been identified, SEA, a highly heat-stable SE, is the most common cause of SFD worldwide. Outbreak investigations have found that improper food handling practices in the retail industry account for the majority of SFD outbreaks. However, several studies have documented prevalence of S. aureus in many food products including raw retail meat indicating that consumers are at potential risk of S. aureus colonization and subsequent infection. Presence of pathogens in food products imposes potential hazard for consumers and causes grave economic loss and loss in human productivity via food-borne disease. Symptoms of SFD include nausea, vomiting, and abdominal cramps with or without diarrhea. Preventive measures include safe food handling and processing practice, maintaining cold chain, adequate cleaning and disinfection of equipment, prevention of cross-contamination in home and kitchen, and prevention of contamination from farm to fork. This paper provides a brief overview of SFD, contributing factors, risk that it imposes to the consumers, current research gaps, and preventive measures.

The human body contains numerous microorganisms, the so-called microbiota that outnumbers human cells. The human nasal passage is one of the primary habitats for microflora as well as pathogenic agents. The nasal passage of the human nostrils leads to the nasopharynx and the upper back part of the throat. The microbial communities inhabiting the nasal passages of humans colonize soon after the birth and distinctly changes over the lifespan of an individual with high inter-individual variations. During a human lifetime, the bacterial colonization of the human nasal cavities and its variations are affected by various factors, including the development of the immunity, hormonal changes, and age. Other affecting factors include environmental variations, e.g., temperature, humidity, pollution, and airborne microbes [1]. In children, a very complex community of bacteria inhabit the nasal passages. Identification of composition and dynamics of these bacteria can provide more insights into the basis of respiratory diseases [2]. Many works have demonstrated that the structure of pediatric bacterial microbiota of the nose is affected by acute respiratory tract infections (ARIs). Some studies have also reported that bacterial flora of the nasal cavities plays a vital role in regulating various immune responses in humans [3]. The interaction between bacterial species in nasal passages and the host include mutualism, commensalism, and pathogenic associations [4]. The most common species of nasal microflora comprise Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus pneumoniae, Micrococcus luteus, Haemophilus influenzae, Proteus vulgaris, Proteus mirabilis, and Bacillus sp. [2, 3]. The members of the genus Staphylococcus are among the common bacteria inhabiting the nasal passages of children and S. aureus, S. epidermidis, and S. hominis are among the most prevalent species. These Gram-positive bacteria are catalase positive, non-motile, and facultative anaerobes. They cause acute to severe infections, such as serious skin infections, pimples, boils, carditis, meningitis, septicemia, arthritis, endocarditis, abscess, osteomyelitis, central venous catheter-associated bacteremia, pneumonia, and ventilator-associated pneumonia. These bacteria produce the enzyme coagulase and are characterized as pathogenic or relatively pathogenic bacteria [5]. Pathogenic strains of the genus Staphylococcus such as S. aureus are usually coagulase-positive. The coagulasenegative strains, e.g., S. epidermidis, are mostly less invasive. However, they are progressively considered pathogens Introduction: Staphylococcus is a genus of pathogenic bacteria, which asymptomatically colonizes the upper respiratory tract of the human. The incidence of invasive Staphylococcal infections and the disease burden are high among children in South Asia, including Pakistan. This study aims to determine the nasal colonization and antimicrobial susceptibility pattern of Staphylococcus species isolated from preschool children in Lahore, Pakistan. Methods: A community-based study was conducted in two camps named Shah Di Khui and Jeevan Haana in Lahore city. A total of 100 nasal samples, were collected from preschool children from lower-middle-class families during January to March 2018. Species identification was performed using the coagulase test, catalase test, and Gram staining. Also, a 370 bp fragment of the tuf gene was targetted using specific primers for the genus Staphylococcus. Antibiotic resistance pattern of the isolates was defined by an antibiotic susceptibility test using a series of antibiotic discs. Results: The results of this study indicated the presence of Staphylococcus species, mainly Staphylococcus aureus in more than 85% of the children. PCR amplification of tuf gene confirmed the identity of the S. aureus isolates from the nasal cultures. Many showed resistance to more than two broad-spectrum antibiotics. Conclusion: The prevalence of nasal colonization of S. aureus was more than 85% among preschool children. Most of the isolates were resistant to β-lactam antibiotics.

Cephalosporins are beta-lactam antibiotics classified into five generations. The newest generation has three representatives: ceftaroline fosamile, the combination ceftolozane/tazobactam (cephalosporin/beta-lactamase inhibitor), and ceftobi-prole medocaril. These new cephalosporins are valuable anti-infective agents, with potent activity against multidrug-resistant bacteria, and with a positive balance between benefits and side effects. However, the fifth-generation cephalosporins should be judiciously used to prevent the occurrence of bacterial resistance phenomenon.