Methicillin-resistant Staphylococcus Aureus Rates Research Articles

Antimicrobial resistance, virulence genes profiling and molecular relatedness of methicillin-resistant Staphylococcus aureus strains isolated from hospitalized patients in Guangdong Province, China.

PurposeThe main objective of this study was to decipher the prevalence, antimicrobial resistance, major virulence genes and the molecular characteristics of methicillin-resistant Staphylococcus aureus (MRSA) isolated from different clinical sources in southern China.Materials and methodsThe present study was performed on 187 non-duplicate S. aureus clinical isolates collected from three tertiary hospitals in Guangdong Province, China, 2010–2016. Antimicrobial susceptibility testing was performed by the disk diffusion method and by measuring the minimum inhibitory concentration. Screening for resistance and virulence genes was performed. Clonal relatedness was determined using various molecular typing methods such as multilocus sequence typing, spa and staphylococcal chromosomal cassette mec (SCCmec) typing. Whole genome sequencing was performed for three selected isolates.ResultsOut of 187 isolates, 103 (55%) were identified as MRSA. The highest prevalence rate was found among the skin and soft tissue infection (SSTI) samples (58/103), followed by sputum samples (25/103), blood stream infection samples (15/103) and others (5/103). Antimicrobial susceptibility results revealed high resistance rates for erythromycin (64.1%), clindamycin (48.5%), gentamicin (36.9%) and ciprofloxacin (33.98%). All isolates were susceptible to vancomycin. Resistance genes and mutation detected were as follows: aac(6’)-aph(2”) (24.3%), dfrG (10.7%), rpoB (21.4%), cfr (0%), fexA (1.94%), gyrA (35.92%), gyrB (0.97%), grlA (20.4%), grlB (10.68%), ermA (21.4%), ermB (18.44%), ermC (21.4%) and lnuA (18.44%). Profiling of virulence genes revealed the following: sea (11.7%), seb (21.4%), sec (0.97%), sed (0.97%), hla (86.41%), hlb (17.48%), hlg (10.68%), hld (53.4%), Tsst-1 (3.9%) and pvl (27.2%). Clonal relatedness showed that ST239-SCCmecA III-t37 clone was the most prevalent clone.ConclusionOur study elucidated the prevalence, antibiotic resistance, pathogenicity and molecular characteristics of MRSA isolated from various clinical sources in Guangdong, China. We found that the infectious rate of MRSA was higher among SSTI than other sources. The most predominant genotype was ST239-SCCmecA III-t37 clone, indicating that ST239-t30 clone which was previously predominant had been replaced by a new clone.

Proportion of asylum seekers carrying multi-drug resistant microorganisms is persistently increased after arrival in the Netherlands

BackgroundSeveral studies have shown a high prevalence of multi-drug resistant organisms (MDRO) amongst asylum seekers when compared to the general population. The aim of this study is to assess the duration of MDRO carriage in this population.MethodsData were retrospectively collected between January 1st 2014 through December 31st 2016. Study material included screening samples for MDRO carriage and clinical samples from asylum seekers in need of medical care. The study focused on methicillin-resistant Staphylococcus aureus (MRSA) and multi-drug resistant Enterobacteriaceae (MDRE). The rates of MRSA and MDRE detected were calculated every four weeks after arrival in the Netherlands.ResultsSamples from 2091 asylum seekers were included. 1270 (60.7%) were female, median age was 26 years (IQR 20–34) and median number of days in the Netherlands until first sample was 67 (IQR 4–235). In the patients’ first obtained samples, the rate of MRSA varied between 4.5 and 13.0% per time interval after arrival. The rate of MDRE fluctuated between 7.4% and 25.0%. No particular decline in positivity rates in first obtained samples was observed after arrival in the Netherlands. In the group of asylum seekers who arrived more than one year ago, MRSA was isolated in a percentage of 5.1% (n = 273, median months after arrival 34.1 (IQR 16.5–63.1)) and MDRE in 9.4% (n = 276, median months after arrival 35.4 (IQR 17–65)).ConclusionTo our knowledge, this is the first study demonstrating that carriage rate of MDRO in asylum seekers remains high even after prolonged stay in the Netherlands. Longitudinal data on MDRO carriage after arrival in countries with a low MDRO prevalence are needed to determine optimal screening strategies, infection control measures and empirical antibiotic therapy.

Screening for Methicillin-resistant Staphylococcus aureus Carriage on the Hands of Healthcare Workers: An Assessment for Hand Hygiene Practices.

ABSTRACTBackgroundMethicillin-resistant Staphylococcus aureus (MRSA) is capable of causing a wide range of infections. Colonized healthcare workers (HCWs) and contaminated hand-touch surfaces act as a potential source of MRSA in hospitals. This study was conducted to detect the carriage of MRSA in the hands of HCWs during patient care to check awareness among HCWs to follow proper hand hygiene protocol.Materials and methodsThis study was a cross-sectional point prevalence study done in wards and intensive care units (ICUs) of a tertiary care hospital. Hand cultures were collected from HCWs after the clinical rounds, without prior information about the procedure. It was done on three consecutive days to include maximum HCWs from the hospital. Cultures were taken before and after the use of alcohol-based hand rub. Hand cultures were obtained by asking HCWs to touch the surface of chromogenic screening agar for MRSA with their fingertips and thumbs of both the hands.ResultsOf a total of 62 HCWs screened, 32 (51.61%) were positive for MRSA. Among these, seven were doctors. After using alcohol-based hand rub, six HCWs were still positive for MRSA. Another important finding on this screening agar was detection of Candida on the hands of HCWs.ConclusionRegular monitoring of hand hygiene compliance is vital to prevent the spread of nosocomial infections. The MRSA screening agar is rapid, simple, cost-effective, and useful to identify the carriage of not only MRSA but also Candida (in the wake of nosocomial outbreaks with Candida auris) in the hands of HCWs. Further studies are required to evaluate the transmission rate of MRSA from HCWs to patients in Indian hospitals.How to cite this articleSharma A, Kalita JM, Nag VL. Screening for Methicillin-resistant Staphylococcus aureus Carriage on the Hands of Healthcare Workers: An Assessment for Hand Hygiene Practices. Indian J Crit Care Med 2019;23(12):590–592.

Methicillin-resistant Staphylococcus aureus carriage among medical students of Jimma University, Southwest Ethiopia

ObjectivesInfections caused by methicillin-resistant Staphylococcus aureus (MRSA) are often difficult to manage due to its resistance to multiple antibiotics. This study aimed to determine the nasal carriage of MRSA and its antimicrobial susceptibility patterns among medical students at the Jimma University medical center (JUMC), Southwest Ethiopia. MethodsAn institution based cross-sectional study was conducted at the JUMC from May to August; 2016. A total of 371 participants were systematically selected. Demographic data was collected using pre-designed questionnaire. Nasal swabs were collected following standard microbiological methods. MRSA was detected using cefoxitin (30μg) disc (Oxoid, UK); and antimicrobial susceptibility tests were performed by disc diffusion method. ResultsA total of 371 students were included. Of these, 84.9% (315/371) were males. The overall prevalence of nasal carriage of S. aureus and MRSA among medical students at JUMC were 22.1% (82/371) and 8.4 % (31/371), respectively. The carriage rate of MRSA among medical intern (20% (16/80)) was higher compared with clinical year-I (3.6% (6/166)) and year-II (7.2% (9/125)) students. Resistance against trimethoprim-sulfamethoxazole, tetracycline and ciprofloxacin were 83.9%, 64.5% and 51.6%, respectively. Longer stay in hospital was significantly associated with the acquisition of MRSA (X2 = 6.93, P value = 0.031). ConclusionThe prevalence of nasal carriage of MRSA was high. Longer stay in hospital environment was associated with the acquisition of MRSA. These findings suggest that infection control efforts focusing the performance of antimicrobial stewardship could have a significant impact on MRSA incidence in this setting.

Antibiotic choice and methicillin-resistant Staphylococcus aureus rate in children hospitalized for atopic dermatitis

BackgroundSystemic antibiotics are commonly used in hospitalized patients with severe atopic dermatitis (AD) exacerbation. However, the antibiotic prescribing patterns are unclear. ObjectiveTo compare the prescribing patterns of antibiotics for children who were hospitalized for AD exacerbation and infectious complications. MethodsElectronic medical records were reviewed for patients younger than 18 years who were hospitalized for AD exacerbation or infectious complications based on International Classification of Diseases, Ninth Revision, Clinical Modification and International Classification of Diseases, Tenth Revision, Clinical Modification codes from 2003 to 2018. The following information was obtained: history, physical examination findings, physician discharge summary, antibiotic treatments, serum tests, and wound cultures. The t test was used to compare clinical and laboratory features. ResultsA total of 174 patients with AD were included. Seventy patients had AD exacerbation and 104 had infectious complications, including cellulitis, abscesses, invasive infections, and eczema herpeticum. The differences between these 2 groups of patients were further verified by length of stay, serum total IgE level, and inflammatory markers (C-reactive protein and erythrocyte sedimentation rate). A total of 56 of 70 patients (80%) with AD exacerbation were treated with a systemic antibiotic. Clindamycin and vancomycin together accounted for 88% of antibiotics on admission for both groups, whereas clindamycin and sulfamethoxazole-trimethoprim were prescribed at similar rates for both groups at discharge. Wound culture results showed that the methicillin-resistant Staphylococcus aureus (MRSA) rate was significantly lower in children with AD exacerbation (22%) vs infectious complications (39%). ConclusionChildren were treated with a high frequency of anti-MRSA antibiotics for inpatient AD exacerbation and infectious complications. However, the rate of MRSA was significantly lower in children with AD exacerbation. Thus, empiric antibiotic choice for infectious complications may not be appropriate for AD exacerbation.

Environmental disinfection with photocatalyst as an adjunctive measure to control transmission of methicillin-resistant Staphylococcus aureus: a prospective cohort study in a high-incidence setting

BackgroundEnvironmental disinfection with continuously antimicrobial surfaces could offer superior control of surface bioburden. We sought to decide the efficacy of photocatalyst antimicrobial coating in reducing methicillin-resistant Staphylococcus aureus (MRSA) acquisition in high incidence setting.MethodsWe performed prospective cohort study involving patients hospitalized in medical intensive care unit. A titanium dioxide-based photocatalyst was coated on high touch surfaces and walls. Five months of pre-intervention data were compared with five months of post-intervention data. The incidence rates of multidrug-resistant organism acquisition and the rates of hospital-acquired blood stream infection, pneumonia, urinary tract infection, and Clostridium difficile–associated diseases were compared using Cox proportional hazards regression analysis.ResultsIn total, 621 patients were included. There was significant decrease in MRSA acquisition rate after photocatalyst coating (hazard ratio, 0.37; 95% confidence interval, 0.14–0.99; p = 0.04). However, clinical identification of vancomycin-resistant Enterococcus spp. and multidrug-resistant Acinetobacter baumannii did not decrease significantly. The hazard of contracting hospital-acquired pneumonia during the intervention period compared to baseline period was 0.46 (95% confidence interval, 0.23–0.94; p = 0.03).ConclusionsIn conclusion, MRSA rate was significantly reduced after photocatalyst coating. We provide evidence that photocatalyst disinfection can be an adjunctive measure to control MRSA acquisition in high-incidence settings.Trial registrationISRCTN Registry (ISRCTN31972004). Registered retrospectively on November 19, 2018.

Methicillin-resistant Staphylococcus aureus in acute otitis externa.

ObjectiveOtologic methicillin-resistant Staphylococcus aureus (MRSA) infection has historically been rare, but given the rise in community-acquired MRSA carriage and infection at other body sites, prevalence rates may be changing. The goal of this study was to determine the prevalence of MRSA in recent otologic cultures from patients with acute otitis externa (AOE).Study designRetrospective review of an institutional microbiologic database.MethodsA retrospective analysis was performed on serial culture isolates taken from the ear at a quaternary care hospital from January 2014 to April 2016. The causative pathogen and antibiotic sensitivity was determined by culture isolation and end point mean inhibitory concentration (MIC) testing. Medical records were reviewed to document patient characteristics, chronicity of infection, symptomatology, and previous treatments.ResultsOver the study period, 173 patients were diagnosed with AOE and underwent otologic cultures of the ear. Fifty-three (30.6%) of cultures grew S.aureus (SA). Of SA infections, 15 (28.3%) were identified as MRSA. MRSA patients were typically older than patients with methicillin-sensitive SA (MSSA) (mean age 46.7 ± 17.9 vs 29 ± 19.4, P = 0.003) and had more medical comorbidities (4 vs 1.7, P = 0.001). Compared to patients with MSSA, patients with MRSA were significantly more likely to have had prior ototopical antibiotic exposure (37% vs 73%, P = 0.019).ConclusionContemporary ear culture isolates at quaternary care center show higher rates of MRSA compared to historical reports in the literature. Clinicians should consider ear cultures to identify MRSA AOE.Level of EvidenceIV.

1226. Can Universal Decolonization Obviate the Need for Screening and Contact Precautions for Carriers of Methicillin-Resistant Staphylococcus aureus in a Medical Intensive Care Unit With MRSA Endemicity? An Interrupted Time Series Study

BackgroundUniversal decolonization of patients in intensive care units (ICUs) has been identified to be an effective infection control strategy of methicillin-resistant Staphylococcus aureus (MRSA). However, it remains uncertain whether universal decolonization can obviate the need for active surveillance testing (AST) and contact precautions (CPs) for MRSA carriers.MethodsWe conducted an interrupted time series study to evaluate whether universal decolonization (daily chlorhexidine bathing plus twice-daily intranasal mupirocin ointment for 5 days) without AST and CPs did affect the incidence of MRSA acquisition on clinical specimen and MRSA bacteremia (the first positive blood culture obtained more than 48 hours after ICU admission) in a medical ICU. There was a 12-month control period of universal decolonization combined with AST and CPs, followed by a 12-month intervention period of universal decolonization without AST and CPs for MRSA carriers. Changes in incidence density (new cases of MRSA acquisition on clinical specimen per 1,000 eligible patient-days) of MRSA were evaluated by segmented Poisson regression, and the cox proportional-hazards regression model was used to compare the differences in incidence of MRSA bacteremia between the two periods.ResultsThe median overall prevalence of MRSA did not differ between the two periods (25.3% vs. 23.4%, P = 0.55), and the segmented Poisson regression analysis revealed that there were no significant differences in both level and trend of MRSA prevalence (P = 0.43 and P = 0.27, respectively). The incidence density of MRSA acquisition on clinical specimen was lower during the intervention period (5.7 vs. 4.5, P = 0.039). However, both level and trend of MRSA incidence density did not differ significantly whether to perform active surveillance and contact precaution or not (P = 0.94 and P = 0.81, respectively). No patient developed MRSA bacteremia during the control period and there were only two patients of MRSA bacteremia during the intervention period, which showed no significant difference (Log rank test, P = 0.21).ConclusionUniversal decolonization without AST and CPs for MRSA carriers do not increase the incidence of MRSA acquisition on clinical specimen and ICU-attributable MRSA bacteremia in ICU with high prevalence rate of MRSA.Disclosures All authors: No reported disclosures.

1224. Drug-Resistance Dynamics of Staphylococcus aureus at a Tertiary Hospital, Beijing, China: 2013–2017

BackgroundTo understand the drug-resistance dynamics of Staphylococcus aureus and provide references for effective control of methicillin-resistant Staphylococcus aureus (MRSA) infection.MethodsAll data were obtained from the healthcare-associated infection surveillance system. Different strains of S. aureus were identified using the VITEK-2 automated system, the drug susceptibility results of resistance and intermediate were classified into resistance. Chi-square test and variation analyses of S. aureus drug-resistant rate were performed.ResultsFrom 2013 to 2017, 2,289 strains of S. aureus were isolated, and the specimen were mostly collected from sputum (721, 31.50%), wound secretion (211, 9.22%), and blood (210, 9.17%). The resistance rate of S. aureus was highest for tigecycline (94.43% in 2013, 100% in 2017) and penicillin (96.49% in 2013, 95.60% in 2017) (P = 0.028). The resistance rates among other drugs such as clindamycin (65.28% in 2013, 71.39% in 2017) and erythromycin (69.62% in 2013, 62.59% in 2017) were more stable (P = 0.056). However, oxacillin (from 73.68% to 34.47%), gentamicin (from 51.51% to 24.13%), and tetracycline (from 46.78% to 30.81%) showed a declining trend (P = 0.017). Meanwhile, there were almost no S. aureus resistance to linezolid, vancomycin, and nitrofurantoin. During the previous 5-year period, MRSA rates decreased sharply and in 2017 rate was 34.47%. In 2017, MRSA was most frequently isolated in orthopedics, emergency ICU, and respiratory.ConclusionThe reduction in drug-resistant MRSA may be evidence of effective antibiotic administration practice. Whereas more comprehensive infection control measures are needed to prevent the transmission of S. aureus and MRSA.Disclosures All authors: No reported disclosures.

Analysis of distribution and drug resistance of pathogens from the wounds of 1 310 thermal burn patients

Objective: To analyze the distribution and drug resistance of pathogens from the wounds of thermal burn patients, so as to provide reliable basis for the rational use of antibiotics and the effective control over nosocomial infection. Methods: Wound samples of 1 310 thermal burn patients admitted into our burn wards from January 2012 to December 2017 were collected and retrospectively analyzed. API bacteria identification panels and automatical bacteria identification equipment were used to identify pathogens. E test was conducted to detect drug resistance of pathogens to vancomycin, tigecycline, and oxacillin. Kirby-Bauer paper disk diffusion method was used to detect drug resistance of pathogens to 31 antibiotics including penicillin G, gentamicin and rifampicin, etc., and drug resistance of fungi to 5 antifungal agents (voriconazole, amphotericin B, fluconazole, itraconazole, and ketoconazole). The WHONET 5.6 software was used to analyze the constituent ratios of Gram-negative bacteria, Gram-positive bacteria, and fungi in each year; the distribution of fungi; the distribution of top 10 bacteria with the highest constituent ratios in each year; the constituent ratios of methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-sensitive Staphylococcus aureus (MSSA); the drug resistance of top 3 bacteria with the highest constituent ratios to commonly used antibiotics in each year; and the drug resistance of Candida to commonly used antifungal agents. Results: (1) Totally 2 183 strains of pathogens were isolated for the first time, including Gram-negative bacteria 1 194 (54.70%) strains, Gram-positive bacteria 879 (40.27%) strains, and fungi 110 (5.04%) strains. From 2012 to 2016, the constituent ratio of Gram-negative bacteria showed a decreasing trend, while that of Gram-positive bacteria showed an increasing trend year by year; and the constituent ratio of fungi was with a significantly increasing trend from 2016 to 2017. (2) Among all the fungi, the constituent ratio of Candida parapsilosis ranked the first, Aflatoxin ranked the second, Candida albicans and Candida tropicalis both ranked the third. (3) From 2012 to 2017, top 10 bacteria with the highest constituent ratios, from high to low, were Staphylococcus aureus, Pseudomonas aeruginosa, Acinetobacter baumannii, Enterobacter cloacae, Escherichia coli, Staphylococcus haemolyticus, Klebsiella pneumoniae, Enterococcus faecalis, Aeromonas hydrophila, and Stenotrophomonas maltophilia respectively. The constituent ratio of Staphylococcus aureus ranked the first in each year. The constituent ratio of Pseudomonas aeruginosa was fluctuating but showed a rising trend comprehensively. The constituent ratio of Acinetobacter baumannii went up after decreasing. (4) Among all the Staphylococcus aureus, constituent ratio of MRSA was above 65.00%, while that of MSSA was below 31.00% in each year. (5) From 2012 to 2017, Staphylococcus aureus resistant to vancomycin, linezolid, or teicoplanin was not detected; the drug-resistant rates of MRSA to penicillin G, oxacillin, gentamicin, rifampicin, tetracycline, ciprofloxacin, ofloxacin, and levofloxacin were above or equal to 80.0% in each year; the drug-resistant rates of Staphylococcus aureus to clindamycin and erythrocin showed an obviously increasing trend, the drug-resistant rates of Staphylococcus aureus to moxifloxacin and queenoputin/daputin in 2017 were higher than those in 2016, while the drug-resistant rates of Staphylococcus aureus to the other 14 antibiotics showed no significant change in trend. From 2012 to 2017, Acinetobacter baumannii was sensitive to polymyxin B and tigecycline; the drug-resistant rate of Acinetobacter baumannii to ceftriaxone was relatively high; the drug-resistant rates of Acinetobacter baumannii to levofloxacin, minocycline, and tetracycline were decreasing while those to the other 14 antibiotics went up after decreasing. From 2012 to 2017, Pseudomonas aeruginosa wasn't resistant to polymyxin B, and its drug-resistant rates to the other 14 antibiotics showed decreasing trends. (6) The drug-resistant rates of Candida albicans to voriconazole, amphotericin B, fluconazole, itraconazole, and ketoconazole were all zero. The drug-resistant rates of non-Candida albicans to voriconazole, fluconazole, itraconazole, and ketoconazole were higher than those of Candida albicans. Conclusions: Among the pathogens from the wounds of thermal burn patients, Staphylococcus aureus, Pseudomonas aeruginosa, and Acinetobacter baumannii had the top 3 constituent ratios; the constituent ratio of non-Candida albicans was obviously higher than that of Candida albicans. The high drug resistance rates of Staphylococcus aureus and Acinetobacter baumanni require more attention from clinicians and the local hospital's infection control department.

Vancomycin Resistant Staphylococcus aureus Reported from Tertiary Care Hospital in Nepal

Objectives: The study was conducted to assess the rate of Methicillin-resistant Staphylococcus aureus (MRSA) among patients and healthcare personnel at Manmohan Memorial College and Teaching Hospital, Kathmandu, Nepal and to evaluate the minimum inhibitory concentration of Vancomycin to MRSA isolates.Methods: A total of 1433 different clinical specimens from patients and 33 nasal swabs from healthcare personnel were subjected to bacteriological investigation following standard protocol. S. aureus were isolated and identified by using standard Microbiological tools. Those isolates were subjected to Antimicrobial susceptibility testing using modified Kirby-Bauer’s disc diffusion method following CLSI guidelines.Results: The rate of S. aureus carriage was found to be 65 (18.9%) in the samples from clinical patients and 24 (72.7%) in the samples from healthcare personnel. The rate of MRSA was found to be 57(85.1%) in patients and 24 (100%) in healthcare personnel. The high distribution of MRSA was found in female of age group 21-30 years (patients: 10.4%; healthcare personnel: 70.8%). Amikacin was found to be most effective antimicrobial. All S. aureus isolates were found to be multidrug resistant (100%). On performing D-test, 10 (17.5%) and 22 (38.6%) of MRSA from clinical specimens showed inducible and constitutive Clindamycin resistance respectively. Whereas, 11 (45.8%) and 4 (16.7%) of MRSA from nasal swabs were found to be inducible and constitutive Clindamycin resistance respectively. Upon performing minimum inhibitory concentration (MIC) test for clinical isolates, 3.5% (2) of MRSA were found to be Vancomycin resistant (VRSA), 54.4% (31) were Vancomycin intermediate (VISA) and 42.1% (24) were found to be Vancomycin sensitive (VSSA). All of the nasal swab MRSA isolates were found sensitive to Vancomycin. Congo red agar method was done for biofilm production. For clinical isolates, 32 (47.8%) were found to be strong, 6 (8.9%) moderate and 29 (43.3%) were non biofilm producer. For nasal swab isolates, 66.7% (16) and 33.3% (8) were found as strong and non-biofilm producer respectively.Conclusion: This study reported the case of VRSA which hasn’t been reported in Nepal. Though present study showed that Vancomycin remains the main choice of treatment of MRSA infection. Therefore, to preserve its value, use of vancomycin should be limited only to those cases where there are clearly needed.

Methicillin-resistant Staphylococcus aureus tracking spread among health-care workers and hospitalized patients in critical wards at a university hospital, Tehran, Iran

Health-care workers may serve as a reservoir for dissemination of methicillin-resistant Staphylococcus aureus (MRSA) to patients in hospital settings. The present study aimed to screen MRSA in nasal swabs of health-care workers and clinical specimens from patients and investigate the possible relationship between these isolates at a university hospital in Tehran, Iran. Additionally, we aimed to identify potential risk factors for MRSA colonization in health-care workers. Staphylococcus aureus strains were isolated from health-care workers and inpatients who completed a questionnaire on risk factors. Cefoxitin disc diffusion test was also used for detection of MRSA. Moreover, all of the MRSA isolates were subjected to pulsed-field gel electrophoresis (PFGE). Colonization rate of MRSA among health-care workers was 22.5%. Furthermore, out of 24 S. aureus isolates obtained from patients, nine (37.5%) were MRSA. Regarding risk factors, the prevalence of nasal MRSA carriage among hospital personnel who used masks was significantly lower than in those without masks (p 0.007). Using PFGE, 10 clusters and 14 singletons were identified among the MRSA isolates. In this regard, most of the MRSA isolates recovered from health-care carriers and patients in intensive care wards, especially general intensive care units, were grouped in certain clusters, indicating intra-ward transmission of the mentioned isolates in these restricted areas. We concluded that screening and decolonization of carriers, contact precautions, prudent use of antibiotics and implementation of active surveillance are recommended strategies for the prevention and control of MRSA transmission in hospital settings.

Molecular characteristics and virulence gene profiles of Staphylococcus aureus causing bloodstream infection

BackgroundThe rate of methicillin-resistant Staphylococcus aureus (MRSA) among the total of S. aureus isolates decreased to 35.3% in 2017 in China. It is unclear whether the molecular characteristics of S. aureus isolates have changed as the rate decreased. ObjectiveThis study aimed to investigate the molecular characteristics and virulence genes profile of S. aureus isolates causing bloodstream infection and analyze the correlation between the prevalence rates of the common sequence types and MRSA. MethodsA total of 112 S. aureus strains from eight hospitals of four cities, including 32 MRSA isolates, were identified and evaluated through multilocus sequence typing, spa typing, and determination of virulence genes. ResultsTwenty-five STs were identified, of which ST5 (21.4%) was the most prevalent, whereas the prevalence of ST239 correlated with the rate of MRSA among all S. aureus isolates. Forty-six spa types were identified, of which t2460 (14.3%) was the most common. clfa, hla, seb, fnbA and hlb were the prevailing virulence genes. 81.3% MRSA and 45.0% methicillin-sensitive S. aureus (MSSA) isolates harbored six or more tested virulence genes. ST5-t2460, seldom noted in bloodborne S. aureus isolates in China, was the most common clone. The prevalence of harboring six or more virulence genes in ST5-t2460 and ST188-t189 were 93.8% and 8.3%, respectively. ConclusionST5-t2460 was the most common clone in S. aureus causing bloodstream infection followed by ST188-t189, which had never been noted in China before. Moreover, ST5-t2460 harbored more virulence genes than ST188-t189, and the prevalence of ST239 clone decreased with the proportion of MRSA among all S. aureus isolates.

Methicillin resistant Staphylococcus aureus (MRSA) carriage among health care workers in a tertiary care hospital in Bhubaneswar

Background: Methicillin resistant Staphylococcus aureus (MRSA) is a multidrug resistant organism emerging as a major cause of hospital acquired infection. In a healthcare setup a patient may acquire MRSA through the hands, clothes and equipments of health care workers. Screening of health care workers colonised with MRSA will be helpful in preventing the spread of this organism in a hospital. With this background the present study was undertaken to estimate the carriage rate of MRSA among healthcare workers in our hospital.Methods: Nasal swabs were collected from 120 health care workers working in Kalinga Institute of Medical Sciences (KIMS), Bhubaneswar during the study period of July- September 2017. The swabs were inoculated onto mannitol salt agar plates for isolation of Staphylococcus aureus. MRSA strains were identified by cefoxitin disc method. Antibiogram of MRSA strains was determined.Results: The prevalence of MRSA carriage among health care workers was 7.5% with the carrier rate being highest among nurses (10%). All the MRSA isolates were 100% resistant to penicillin. MRSA isolates were 90% resistant to amoxyclav, 60% to cotrimoxazole and erythromycin and 50% to clindamycin.Conclusions: Although the prevalence of MRSA among health care workers in our hospital is not alarming, it is important to emphasize the need for stringent hospital infection control policies to reduce the spread of MRSA to susceptible individuals.

Coordinated surveillance of the multi drug resistant organisms in a French University Hospital: Results since 2013

Introduction The control of the cross-transmission of multi drug resistant organisms (MDRO) is a major concern in the healthcare centers. That is the purpose of one of the axes of the French national program of prevention of healthcare-associated infections (Propias). To adapt the recommendations, a French multicenter university hospital started a coordinated and standardized surveillance of MDRO since 2013. The objective of the study is to know the global incidence rate of MDROs and to follow this rate along time. Methods An active standardized surveillance of MDRO was carried out in a university hospital of about 6000 beds. The methodology was based on the French national MDRO's surveillance network (BMR-RAISIN). All methicillin resistant Staphylococcus aureus (MRSA), and extended spectrum beta-lactamase Enterobacteriaceae (ESBLE) detected in clinical specimen performed between April 1, and June 30, in 2013, 2015, and 2017, in the hospitalized patients (in conventional ward or week hospitalization) were included. Screening for colonization and environment samples were excluded. To describe the population with MDROs, we collected data on patient characteristics, specimen sample site, acquired or imported, infection or colonization, ESBLE species, resistance profile for certain antibiotics markers. To calculate the incidence rates, the number of hospitalization days was collected for each period of surveillance. Results For the 3 surveillance periods, a total of 1191 MDRO were included, distributed in 989 ESBLEs (93.04%) and 202 MRSAs (16.96%). The main ESBLE species were Escherichia coli (41.6%), Klebsiella pneumoniae (31.6%) and Enterobacter cloacae (11.4%). The proportion of E. coli decreased along time to the detriment of the other Enterobacteriaceae species, in particular for imported ESBLE (P = 0.0304), while the time evolution was not statistically significant for acquired ESBLEs (P = 0.0555). There were 506 acquired MDROs (42.5%) and 651 imported (54.7%). The most frequent sample types were urine samples (N = 608, 52.9%), respiratory specimens (N = 185, 16.1%) and bloodstream specimens (N = 123, 10.7%). MDROs were responsible of 786 infections among the 1108 for which the information was available (70.9%). Fifteen ESBLEs among 952 were imipenem-resistant (1.6%), and 54 among 868 were ertapenem-resistant (6.2%). The proportion of ertapenem resistant ESBLE was 2-fold increased between 2013 and 2017, from 4.3% to 8.4% (P = 0.06). A 20% > decreased of the incidence rate of MRSA was observed between 2013 and 2017: from 0.25/1000 hospitalization-days in 2013, to 0.17 in 2015, and 0.20 in 2017. This decrease was higher in imported MRSA group. A 62.7% > increased of the ESBLE incidence rate was observed, from 0.83/1000 hospitalization-days in 2013 and 2015 to 1.35 in 2017. This increase was observed both for the imported and acquired ESBLE but was higher for the imported ones. Conclusions The implementation of this surveillance allowed the University hospital to know its global incidence rate of MRSA and ESBLE, and to propose straightaway coordinated prevention measures. We observed over the 3 periods of surveillance a decrease in the MRSA incidence and an increase in the ESBLE incidence. These results are coherent with the national network data. We observed also an increase in the proportion of ertapenem-resistant ESBLE. These data should be construed in the light of the change of the national epidemiology of the antibiotic resistance in Enterobacteriaceae, and particularly the increasing number of episodes of carbapenem-producing Enterobacteriaceae which the university hospital have to manage. These data suggest that a strengthening of campaigns of preventing MDROs cross transmission. Appropriate antibiotic use might also help to limit de diffusion of MDRO in hospital and community.

Colonization With Methicillin-Resistant Staphylococcus aureus Upon Intensive Care Unit Admission: Incidence and Risk Factors

Background: Since earlier identification of methicillin-resistant Staphylococcus aureus (MRSA)-colonized patients could be helpful for reducing the overall frequency of S.aureus infections, the investigation of persons colonized with MRSA is considered to be a key component of MRSA infection prevention programs, particularly among ICU patients. Objectives: The aim of the present study was to evaluate the prevalence of nasal and extra-nasal carriers of MRSA and risk factors associated with MRSA colonization among adult patients admitted to the ICU. Methods: In a cross-sectional study, 164 adult patients who were admitted to the ICU of a teaching hospital were screened for nasal and extra-nasal carriage of MRSA. In addition, the ICU-hospitalized patients were evaluated for MRSA acquisition during their ICU stay. Results: Out of the 164 patients admitted to the ICU, 12 (7.3%) patients were methicillin-susceptible Staphylococcus aureus (MSSA) carriers, and 12 (7.3%) patients carried MRSA. Four (16.6%) patients were colonized at single or multiple extra-nasal sites based on neg- ative nares screening. Of the 15 remaining patients hospitalized at the ICU, one (6.7%) patient acquired MRSA. The patients colonized with MRSA had more advanced ages (P = 0.008), longer hospital stays before being transferred to the ICU (P > 0.001), more under- lying diseases with chronic obstructive pulmonary disease (COPD) (P = 0.028), and had undergone surgery (P = 0.003). Patients transferred from the surgical wards to the ICU were found to have significantly higher carriage rates of MRSA (P = 0.041). Conclusions: The prevalence of MRSA colonization upon ICU admission at our hospital was relatively high, and routine MRSA screening is suggested, especially for patients who have certain risk factors. In addition, extra-nasal MRSA screenings upon ICU admission will help in the early detection of MRSA.

Dose-response associations of methicillin-resistant Staphylococcus aureus between school environmental contamination and nasal carriage by elementary students.

BackgroundMethicillin-resistant Staphylococcus aureus (MRSA) can cause serious infections in elementary students. Therefore, we aimed to elucidate the quantitative associations of school environmental contamination with nasal carriage of MRSA by students in a dose-response manner. Phenotypic and molecular characterizations were performed to further assess the associations.Materials and methodsA cross-sectional study was conducted from March to August 2016 in eight elementary schools in Guangzhou, China. A multistage stratified cluster sampling design was used to include Chinese students and selected classes. Nasal swabs from students and environmental swabs from the schools were collected. The dose-response relationship was examined using multivariate logistic regression modeling with cluster-correlated robust variance estimates to account for correlations of isolates between the environment and the students.ResultsThe prevalence rates of MRSA among 1705 students and 1240 environment samples were 10.15% and 3.87%, respectively. There were positive prevalence associations of school (odds ratio 1.09, 95% confidence interval [CI] 1.05–1.13) and class (odds ratio 1.03, 95% CI 1.01–1.06) environmental contamination with nasal carriage of MRSA isolates by students.ConclusionsComparisons of MRSA isolates between the environment and the students in terms of phenotypic and molecular characterization were mostly insignificant. School environmental contamination with MRSA was positively associated with MRSA nasal carriage by elementary students. Disinfection measures and education regarding hand hygiene should be considered to decrease the prevalence of MRSA nasal carriage among students.

Multi-level analysis of bacteria isolated from inpatients in respiratory departments in China.

With the different situation for clinical antibiotic usage and its management in different regions and medical institutions, the antimicrobial resistance varied in different level. However, the epidemiological data of multi-drug resistant (MDR) strains from the department of respiration is limited. Thus, this study aims to investigate the epidemiology of bacteria isolated from inpatients of respiratory departments, and analyze the distribution variation of major multi-drug resistant bacteria in China. Based on data from China Antimicrobial Resistance Surveillance System (CARSS) in 2015, 50,417 non-duplicate isolates obtained from inpatients of respiratory departments from 91 general hospitals in seven regions of China were enrolled in the study. The distribution of methicillin-resistant Staphylococcus aureus (MRSA), carbapenem-resistant Escherichia coli (CREC) and Klebsiella pneumoniae (CRKP), carbapenem-resistant Pseudomonas aeruginosa (CRPA) and Acinetobacter baumannii (CRAB), extended-spectrum β-lactamases-producing E. coli (ESBL-EC) and K. pneumoniae (ESBL-KP), were further analyzed by geographic regions, age groups, wards and specimen types. The major specimens type were sputum (81.6%, 41,131/50,417), followed by blood (5.3%, 2,649/50,417), urine (4.5%, 2,249/50,417) and bronchoalveolar lavage fluid (BALF) (3.2%, 1,620/50,417). The top four bacteria species isolated from sputum and BALF were similar: K. pneumonia (18.9% and 14.8%, respectively), P. aeruginosa (13.6% and 22.2%, respectively), A. baumannii (11.3% and 11.9%, respectively) and S. pneumonia (11.1% and 9.6%, respectively). The four most common bacteria species were K. pneumonia (17.2%), P. aeruginosa (12.1%), A. baumannii (10.4%) and S. pneumonia (10.1%) in tertiary hospitals but K. pneumonia (20.8%), P. aeruginosa (16.3%), E. coli (11.3%) and A. baumannii (6.9%) in secondary hospitals. The top four bacteria species in respiratory intensive care unit (RICU) were A. baumannii (25.8%), P. aeruginosa (13.1%), K. pneumonia (12.2%) and S. aureus (9.2%). The prevalence of CRKP, CRPA and CRAB in tertiary hospitals was significantly higher than that in secondary hospitals (5.2% vs. 2.5%, 23.8% vs. 12.8% and 53.5% vs. 33.9%, respectively) (all P<0.05). However, the prevalence of ESBL-EC in secondary hospitals was higher than in tertiary ones (63.9% vs. 55.0%, P=0.011). The prevalence of MRSA, CRKP, CRAB, CRPA, ESBL-EC, ESBL-KP in RICU were higher than that in non-ICU respiratory departments (76.5% vs. 35.7%, 20.1% vs. 4.1%, 90.6% vs. 45.5%, 64.2% vs. 19.3%, 47.2% vs. 28.3% and 43.0% vs. 11.2%, respectively) (all P<0.01). Among seven regions in China, central area had the highest detection rates of MRSA (70.3%, 237/337), CRPA (30.9%, 376/1,218), CRAB (71.8%, 487/678) and ESBL-KP (38.8%, 241/621). The prevalence of ESBL-EC and ESBL-KP in pediatric group (68.2% and 55.3%, respectively) was higher than that in geriatric group (54.2% and 27.1%, respectively) and adult group (51.1% and 15.1%, respectively) (all P<0.001). In China, the predominant bacterial pathogens in the respiratory ward were Enterobacteriaceae and non-fermentative bacteria. High prevalence of ESBL-EC and ESBL-KP isolated from lower respiratory tract (LRT) was revealed in primary hospitals and pediatric patients.

Racial Disparities in Invasive Methicillin-resistant Staphylococcus aureus Infections, 2005-2014.

Despite substantial attention to the individual topics, little is known about the relationship between racial disparities and antimicrobial-resistant and/or healthcare-associated infection trends, such as for methicillin-resistant Staphylococcus aureus (MRSA). We analyzed Emerging Infections Program 2005-2014 surveillance data (9 US states) to determine whether reductions in invasive MRSA incidence (isolated from normally sterile body sites) affected racial disparities in rates. Case classification included hospital-onset (HO, culture >3 days after admission), healthcare-associated community onset (HACO, culture ≤3 days after admission and dialysis, hospitalization, surgery, or long-term care residence within 1 year prior), or community-associated (CA, all others). Negative binomial regression models were used to evaluate the adjusted rate ratio (aRR) of MRSA in black patients (vs in white patients) controlling for age, sex, and temporal trends. During 2005-2014, invasive HO and HACO (but not CA) MRSA rates decreased. Despite this, blacks had higher rates for HO (aRR, 3.20; 95% confidence interval [CI], 2.35-4.35), HACO (aRR, 3.84; 95% CI, 2.94-5.01), and CA (aRR, 2.78; 95% CI, 2.30-3.37) MRSA. Limiting the analysis to chronic dialysis patients reduced, but did not eliminate, the higher HACO MRSA rates among blacks (aRR, 1.83; 95% CI, 1.72-1.96), even though invasive MRSA rates among dialysis patients decreased during 2005-2014. These racial differences did not change over time. Previous reductions in healthcare-associated MRSA infections have not affected racial disparities in MRSA rates. Improved understanding of the underlying causes of these differences is needed to develop effective prevention interventions that reduce racial disparities in MRSA infections.

Prevalence of Methicillin-resistant Staphylococcus aureus in Abeokuta, Nigeria

This study examined the prevalence of Methicillin-resistant Staphylococcus aureus (MRSA) in clinical samples of patients in Abeokuta, Ogun State, Nigeria using standard recommended procedures. A total of 338 clinical specimens of Pus, Aspirate, Ear and Wound swabs were collected from three major health facilities in Abeokuta, Nigeria. Each sample was cultured for bacteria isolates and examined for colonial and cellular morphology while biochemical identification was performed. Of the clinical samples collected, 50.3% were collected from male and highest rate of 37.9% was from age group 0-9 years and least rate of 7.6% was from age 10-19 and 40-49years. Only 32.9% samples were ear swabs, wound swabs (29.2%) and lowest rate of 16.8% for aspirate. Of the 161 Staphylococcus aureus (32.2%) isolated; there was no significant disparity found in relation to the study sites (c2=7.145, p-value = 0.308). The present study indicated a high prevalence rate of MRSA that require empirical and urgent intervention to prevent staphylococcal infection among the hospital patients and its outbreak.