Methicillin-resistant Staphylococcus Aureus Prevention Research Articles

The Prevalence, Epidemiological, and Molecular Characterization of Methicillin-Resistant Staphylococcus aureus (MRSA) in Macau (2017-2022).

Macau, recognized as a global tourism hub and the world's most densely populated region, provides a unique environment conducive to methicillin-resistant Staphylococcus aureus (MRSA) transmission in healthcare and community settings, posing a significant public health concern both locally and globally. The epidemiology and molecular characteristics of MRSA in the distinct city of Macau remain largely unelucidated. This five-year longitudinal study (2017-2022) examined the local prevalence and molecular typing of MRSA in Macau, with future MRSA type distribution predicted through ARIMA modeling. We subsequently analyzed the epidemiological characteristics of MRSA, including specimen source, clinical department, collection year, season, patient age, sex, and the annual number of tourists. Comprehensive antibiotic resistance profiles of the strains were also assessed. Of 504 clinically isolated S. aureus strains, 183 (36.3%) were identified as MRSA by the cefoxitin disk diffusion method and validated through multi-locus sequence typing (MLST). The MRSA detection rate showed an upward trend, increasing from 30.1% in 2017 to 45.7% in 2022. SCCmec type IV was predominant (28.9%), followed by types II (25.4%), III (22.1%), and V (22.1%). The primary sources of MRSA isolates were sputum (39.2%) and secretions (25.6%). Older age emerged as a risk factor for MRSA infection, whereas no significant associations were found with seasonal variations, gender, or the annual number of tourists. Despite displaying universal resistance to cefoxitin, oxacillin, and benzylpenicillin, MRSA isolates in Macau remained fully sensitive to vancomycin, tigecycline, quinupristin, nitrofurantoin, and linezolid. Continuous surveillance and analysis of MRSA distribution in Macau could provide invaluable insights for the effective management of MRSA prevention and control measures within healthcare settings.

Are Contact Precautions "Essential" for the Prevention of Healthcare-associated Methicillin-Resistant Staphylococcus aureus?

The recently updated Society for Healthcare Epidemiology of America, the Infectious Diseases Society of America, and the Association of Professionals in Infection Control practice recommendations for methicillin-resistant Staphylococcus aureus (MRSA) prevention in acute care facilities list contact precautions (CPs) for patients known to be infected or colonized with MRSA as an "essential practice," meaning that it should be adopted in all acute care facilities. We argue that existing evidence on benefits and harms associated with CP do not justify this recommendation. There are no controlled trials that support broad use of CP for MRSA prevention. Data from hospitals that have discontinued CP for MRSA have found no impact on MRSA acquisition or infection. The burden and harms of CP remain concerning, including the environmental impact of increased gown and glove use. We suggest that CP be included among other "additional approaches" to MRSA prevention that can be implemented under specific circumstances (eg outbreaks, evidence of ongoing transmission despite application of essential practices).

Active Surveillance and Contact Precautions for Preventing Methicillin-Resistant Staphylococcus aureus Healthcare-Associated Infections During the COVID-19 Pandemic.

Statistically significant decreases in methicillin-resistant Staphylococcus aureus (MRSA) healthcare-associated infections (HAIs) occurred in Veterans Affairs (VA) hospitals from 2007 to 2019 using a national policy of active surveillance (AS) for facility admissions and contact precautions for MRSA colonized (CPC) or infected (CPI) patients, but the impact of suspending these measures to free up laboratory resources for testing and conserve personal protective equipment for coronavirus disease 2019 (COVID-19) on MRSA HAI rates is not known. From July 2020 to June 2022 all 123 acute care VA hospitals nationwide were given the rolling option to suspend (or re-initiate) any combination of AS, CPC, or CPI each month, and MRSA HAIs in intensive care units (ICUs) and non-ICUs were tracked. There were 917 591 admissions, 5 225 174 patient-days, and 568 MRSA HAIs. The MRSA HAI rate/1000 patient-days in ICUs was 0.20 (95% confidence interval [CI], .15-.26) for facilities practicing "AS + CPC + CPI" compared to 0.65 (95% CI, .41-.98; P < .001) for those not practicing any of these strategies, and in non-ICUs was 0.07 (95% CI, .05-.08) and 0.12 (95% CI, .08-.19; P = .01) for the respective policies. Accounting for monthly COVID-19 facility admissions using a negative binomial regression model did not change the relationships between facility policy and MRSA HAI rates. There was no significant difference in monthly facility urinary catheter-associated infection rates, a non-equivalent dependent variable, in the policy categories in either ICUs or non-ICUs. Facility removal of MRSA prevention practices was associated with higher rates of MRSA HAIs in ICUs and non-ICUs.

Community-Associated Methicillin-Resistant Staphylococcus Aureus in the Oral Cavity

The oral cavity is habitat to a wide variety of commensal flora, which may act as a reservoir of factors that influence drug resistance. Bacteria in the oral cavity create biofilms, which makes it easier for horizontal gene transfer to result in the accumulation of antibiotic resistance genes. Methicillin-resistant Staphylococcus aureus (MRSA) carriage rates in the oral cavity are high, according to recent studies. The widespread use of antibiotic prophylaxis among at-risk dental procedure applicants may facilitate MRSA establishment in the mouth. These modifications in the epidemiology of MRSA have significant ramifications for clinical practice, methodological approaches to MRSA carriage studies, and MRSA prevention efforts.

Prevalence and clinical characteristics of methicillin-resistant Staphylococcus aureus infections among dermatology inpatients: A 7-year retrospective study at a tertiary care center in southwest China.

Increased rates of methicillin-resistant Staphylococcus aureus (MRSA) antibiotic resistance and the associated morbidity have increased dermatologists' attention to skin and soft tissue MRSA infections. However, the clinical characterization of MRSA skin and soft tissue infections (SSTIs) in Southwest China is lacking, which precludes optimal prevention and treatment of these infections. This study was conducted to characterize the prevalence, clinical comorbidities and antibiotic susceptibility of MRSA isolates from SSTIs, including community-associated (CA) and healthcare-associated (HA) isolates. In the Dermatology Inpatient Department of the First Affiliated Hospital of Guangxi Medical University, a retrospective study was conducted on data, including patient demographics and clinical information, from culture-confirmed S. aureus isolated from skin and soft tissue between January 1, 2015, and December 31, 2021. Isolate susceptibility to 13 antibiotics was determined using the Vitek 2 system. From among 864 S. aureus strains, we identified 283 MRSA (32.75%) isolates comprising 203 CA-MRSA and 80 HA-MRSA isolates. The average rate of CA-MRSA isolation for MRSA SSTIs was 71.73%. The HA-MRSA isolation rate for MRSA SSTIs increased significantly. HA-MRSA-infected patients were older. The most common dermatological presentation of CA-MRSA infection was staphylococcal scalded skin syndrome, while the comorbidity severe drug eruption was significantly associated with HA-MRSA infection. One CA-MRSA strain was resistant to linezolid, and one HA-MRSA strain had an intermediate phenotype for vancomycin; both strains had low sensitivity to clindamycin and erythromycin (3.70%~19.40%). However, HA-MRSA isolates were more susceptible to trimethoprim/sulfamethoxazole. CA-MRSA is a predominant pathogen causing SSTIs, and HA-MRSA infection incidence is increasing gradually. Both strains showed increasing antibiotic resistance. Our data on MRSA susceptibility may guide dermatologist antibiotic treatment decisions. Dermatologists should consider these identified comorbidities of MRSA SSTIs when patients are admitted and initiate early prevention and treatment of MRSA.

Insights into the Effects and Mechanism of Andrographolide-Mediated Recovery of Susceptibility of Methicillin-Resistant Staphylococcus aureus to β-Lactam Antibiotics.

The frequent resistance associated with β-lactam antibiotics and the high frequency of mutations in β-lactamases constitute a major clinical challenge that can no longer be ignored. Andrographolide (AP), a natural active compound, has been shown to restore susceptibility to β-lactam antibiotics. Fluorescence quenching and molecular simulation showed that AP quenched the intrinsic fluorescence of β-lactamase BlaZ and stably bound to the residues in the catalytic cavity of BlaZ. Of note, AP was found to reduce the stability of the cell wall (CW) in methicillin-resistant Staphylococcus aureus (MRSA), and in combination with penicillin G (PEN), it significantly induced CW roughness and dispersion and even caused its disintegration, while the same concentration of PEN did not. In addition, transcriptome sequencing revealed that AP induced a significant stress response and increased peptidoglycan (PG) synthesis but disrupted its cross-linking, and it repressed the expression of critical genes such as mecA, blaZ, and sarA. We also validated these findings by quantitative reverse transcription-PCR (qRT-PCR). Association analysis using the GEO database showed that the alterations caused by AP were similar to those caused by mutations in the sarA gene. In summary, AP was able to restore the susceptibility of MRSA to β-lactam antibiotics, mainly by inhibiting the β-lactamase BlaZ, by downregulating the expression of critical resistance genes such as mecA and blaZ, and by disrupting CW homeostasis. In addition, restoration of susceptibility to antibiotics could be achieved by inhibiting the global regulator SarA, providing an effective solution to alleviate the problem of bacterial resistance. IMPORTANCE Increasingly, alternatives to antibiotics are being used to mitigate the rapid onset and development of bacterial resistance, and the combination of natural compounds with traditional antibiotics has become an effective therapeutic strategy. Therefore, we attempted to discover more mechanisms to restore susceptibility and effective dosing strategies. Andrographolide (AP), as a natural active ingredient, can mediate recovery of susceptibility of MRSA to β-lactam antibiotics. AP bound stably to the β-lactamase BlaZ and impaired its hydrolytic activity. Notably, AP was able to downregulate the expression of critical resistance genes such as mecA, blaZ, and sarA. Meanwhile, it disrupted the CW cross-linking and homeostasis, while the same concentration of penicillin could not. The multiple inhibitory effect of AP resensitizes intrinsically resistant bacteria to β-lactam antibiotics, effectively prolonging the use cycle of these antibiotics and providing an effective solution to reduce the dosage of antibiotics and providing a theoretical reference for the prevention and control of MRSA.

Outbreak of MRSA in a Gynecology/Obstetrics Department during the COVID-19 Pandemic: A Cautionary Tale.

Since March 2020, the COVID-19 pandemic forced hospitals worldwide to intensify their infection control measures to prevent health care-associated transmission of SARS-CoV-2. The correct use of personal protective equipment, especially the application of masks, was quickly identified as priority to reduce transmission with this pathogen. Here, we report a nosocomial cluster of methicillin-resistant Staphylococcus aureus (MRSA) that occurred during the COVID-19 pandemic in a gynecology/obstetrics department, despite these intensified contact precautions. Five MRSA originating from clinical samples after surgical intervention led to an outbreak investigation. Firstly, this included environmental sampling of the operation theatre (OT) and, secondly, a point prevalence screening of patients and health care workers (HCW). All detected MRSA were subjected to whole genome sequencing (WGS) and isolate relatedness was determined using core genome multilocus sequence typing (cgMLST). WGS revealed one MRSA cluster with genetically closely related five patient and two HCW isolates differing in a single cgMLST allele at maximum. The outbreak was terminated after implementation of infection control bundle strategies. Although contact precaution measures, which are also part of MRSA prevention bundle strategies, were intensified during the COVID-19 pandemic, this MRSA outbreak could take place. This illustrates the importance of adherence to classical infection prevention strategies.

Methicillin-resistant Staphylococcus aureus infections in postpartum period

The overall risk of methicillin-resistant Staphylococcus aureus (MRSA) in obstetric populations is unknown. MRSA infection incidence has increased in pregnant women and neonates even if prevention techniques of MRSA have improved. MRSA infections affect both mothers and their infants. MRSA is the most common pathogen responsible for postpartum mastitis. There are also other postpartum infections with MRSA such as cellulitis, pelvic thrombophlebitis, pneumonia, septicemia, cesarean wound infections, episiotomy infections and urinary tract infections. The objectives of this review were to identify the most frequent risk factors for postpartum MRSA infection and to determine the frequency of antibiotic-resistant Staphylococcus aureus infections after delivery. A literature review was conducted using PubMed and we used the following key words “MRSA infection in postpartum”, “risk factors for postpartum MRSA infection”. We are included in our review 27 articles from the last 20 years which presented rare cases of MRSA infection in postpartum and those which identified the risk factors of this infection after delivery. Infections with MRSA appear to be more frequent among pregnant women colonized with MRSA. Early identification of MRSA, early diagnosis and appropriate treatment of infection is mandatory for a good prognosis. By now, vigilance and effective MRSA prevention strategies are considered essential to limit the spread and infection.

Comparison of Outcomes of Community and Hospital-Acquired Methicillin- Susceptible and Methicillin-Resistant Staphylococcus Aureus Infections

Introduction: Staphylococcus Aureus (S. aureus) causes community (CA) and hospital-acquired (HA) infections that kills millions of patients every year. It is unclear if Methicillin-resistant Staphylococcus Aureus (MRSA) have higher mortality and complication than Methicillin -susceptible Staphylococcus Aureus (MSSA) infections in CA and HA infections. Methods: This retrospective study included confirmed of cases S. aureus infections, which classified as MSSA or MRSA and CA or HA infections We assessed 30-day mortality, rate of Septic Shock and Acute Renal Injury (AKI) as outcomes measures. Results: Of the total 183 cases included, we found no differences between MRSA and MSSA cases in mortality (P=0.734) and other outcomes. Likewise, CA and HA cases Similar mortality. However, HA cases developed a higher rate of AKI compared to CA cases. We observed this increased rate of AKI only in HA MSSA cases. Conclusion: This study offers a new perspective on HA MSSA as a serious pathogen as MRSA, that requires intervention to prevent its spread. Future research needed to identify new measures for MSSA prevention and investigate whether current MRSA prevention strategies are effective in MSSA. Keywords: Methicillin-resistant; MRSA; MSSA; Saudi Arabia; Staphylococcus aureus

Expanding an Economic Evaluation of the Veterans Affairs (VA) Methicillin-resistant Staphylococcus aureus (MRSA) Prevention Initiative to Include Prevention of Infections From Other Pathogens.

In October 2007, Veterans Affairs (VA) launched a nationwide effort to reduce methicillin-resistant Staphylococcus aureus (MRSA) transmission called the National MRSA Prevention Initiative. Although the initiative focused on MRSA, recent evidence suggests that it also led to a significant decrease in hospital-onset (HO) gram-negative rod (GNR) bacteremia, vancomycin-resistant Enterococci (VRE), and Clostridioides difficile infections. The objective of this analysis was to evaluate the cost-effectiveness and the budget impact of the initiative taking into account MRSA, GNR, VRE, and C. difficile infections. We developed an economic model using published data on the rate of MRSA hospital-acquired infections (HAIs) and HO-GNR bacteremia in the VA from October 2007 to September 2015, estimates of the attributable cost and mortality of these infections, and the costs associated with the intervention obtained through a microcosting approach. We explored several different assumptions for the rate of infections that would have occurred if the initiative had not been implemented. Effectiveness was measured in life-years (LYs) gained. We found that during fiscal years 2008-2015, the initiative resulted in an estimated 4761-9236 fewer MRSA HAIs, 1447-2159 fewer HO-GNR bacteremia, 3083-3602 fewer C. difficile infections, and 2075-5393 fewer VRE infections. The initiative itself was estimated to cost $561 million over this 8-year period, whereas the cost savings from prevented MRSA HAIs ranged from $165 to $315 million and from prevented HO-GNR bacteremia, CRE and C. difficile infections ranged from $174 to $200 million. The incremental cost-effectiveness of the initiative ranged from $12 146 to $38 673/LY when just including MRSA HAIs and from $1354 to $4369/LY when including the additional pathogens. The overall impact on the VA's budget ranged from $67 to$195 million. An MRSA surveillance and prevention strategy in VA may have prevented a substantial number of infections from MRSA and other organisms. The net increase in cost from implementing this strategy was quite small when considering infections from all types of organisms. Including spillover effects of organism-specific prevention efforts onto other organisms can provide a more comprehensive evaluation of the costs and benefits of these interventions.

Prevalence of Mastitis and Phenotypic Characterization of Methicillin-Resistant Staphylococcus aureus in Lactating Dairy Cows of Selected Dairy Farms in and Around Adama Town, Central Ethiopia.

Background:The emergence of Methicillin resistant Staphylococcus aureus (MRSA) poses a serious public health threat. Strains of Staphylococcus aureus resistant to β-lactam antibiotics are known as MRSA. MRSA has gained attention as community pathogen. MRSA has been increasingly reported as emerging problem in veterinary medicine. However, little is known in Ethiopia. This study was, therefore, conducted to identify MRSA, to determine its drug susceptibility patterns, and mastitis infection in dairy cattle in and around Adama town, Central Ethiopia.Methods:A cross-sectional study was conducted to estimate the occurrence of MRSA in mastitic dairy cows in and around Adama town, central Ethiopia. A total of 384 lactating cows were included from the conveniently selected dairy farms in the study area. Approximately 10 ml of milk was aseptically collected from clinical and subclinical mastitic cows into sterile universal bottles after discarding the first 3 milking streams. Then, Staphylococcus aureus was isolated using the conventional bacteriological procedure. Resistance to methicillin was detected using the Kirby-Bauer disc diffusion antibiotic susceptibility method. Oxacillin disc was used to detect methicillin resistant Staphylococcus aureus strains. Antimicrobial susceptibility test was conducted against MRSA strains using streptomycin (S, 10 µg), amoxicillin (Am, 25 µg), kanamycin (k, 30 µg), nalidixic acid (NA, 30 µg), oxytetracycline (OT, 30 µg) sulphonamide (S, 300 µg) and ceftriazole (CRO, 30 µg).Results:The study found that the prevalence of mastitis was 121(31.5%). Among this 37(30.6%) were clinical mastitis and 84 (69.4%) of them were sub-clinical mastitis. Of 121 mastitis cases, Staphylococcus aureus was isolated in 37 (30.6%) of mastitic cow milk samples. The prevalence of mastitis was significantly affected by breed, age, floor type and hygienic status of the milkers (P < .05). Moreover, 32.4% of Staphylococcus aureus isolates were resistant to oxacillin. A total of 75% percent of MRSA isolates were resistant to amoxicillin, 66.7% were resistant to oxytetracycline, and 50% were resistant to sulphonamide. However, 75% of MRSA isolates were susceptible to kanamycin, 58.3% were susceptible to streptomycin, and 50% were susceptible to nalidixic acid.Conclusion:The study revealed that relatively high number of strains are resistant to the antibiotics commonly used in the therapeutic protocol of many human and animal infections. Therefore, antimicrobial susceptibility test should be carried out at a regular basis and proper hygienic practices should be introduced at farm level. Creating public awareness about transmission, prevention and control of MRSA should also be considered.

Assessing the Potential Impact of a Long-Acting Skin Disinfectant in the Prevention of MRSA

Background: Healthcare-associated transmission of methicillin-resistant Staphylococcus aureus (MRSA) remains a persistent problem despite advances in prevention. The use of chlorhexidine gluconate (CHG) as a means of decolonizing patients, either through targeted decolonization or daily bathing, is a frequently used measure to supplement other MRSA reduction interventions. However, there is room for new and innovative decolonizing agents. We explored the potential utility of a long-acting CHG-like disinfectant with a persistent protective effect as well as an immediate decolonizing action in the prevention of MRSA acquisition as well as the subsequent development of clinical illness and MRSA-related mortality. Methods: We modeled MRSA transmission throughout an 18-bed intensive care unit, based on previously published models. A baseline model with no daily decolonizing protocol was used as a baseline and was compared to a scenario assuming that patients were bathed with CHG, which decolonizes them but provides no ongoing protection, as well as a scenario involving a hypothetical treatment that both decolonizes and provides ongoing protection from subsequent colonization. We varied the duration and efficacy of this protection to fully explore the potential utility of such a treatment. Results: The results of the simulations are shown in Fig. 1, where duration and efficacy of protection varied. The number of MRSA acquisitions from each combination is depicted as a single point, with blue points indicating correspondingly fewer MRSA acquisitions. Overall, improved efficacy of the hypothetical disinfectant resulted in immediate improvements in MRSA acquisition rates when compared to the baseline. To see major improvements in the MRSA acquisition rate due to the duration of infection, that duration must be well above 10 hours in many scenarios. There is also little evidence of synergy between the two. Conclusions: Based on recent results suggesting CHG has a relatively modest per-use efficacy (&lt;.20), there is room for improvement in the formulation and administration of decolonizing agents. Although there has been considerable excitement about the possibility of long-acting agents that not only decolonize but provide long-acting protection against colonization, these results suggest that such protection would only result in markedly decreased acquisition rates only if that duration of protection was extremely long, or if the agent itself was also considerably more efficacious than CHG. These results may be used to help consider the necessary study size for clinical studies of these agents in the future, or to set research priorities and properly calibrate expectations.Funding: NoneDisclosures: None

Methicillin-resistant Staphylococcus aureus: Knowledge, attitude and perception among medical students in a private institution in Ogun State, Nigeria

Background: Methicillin-resistant Staphylococcus aureus(MRSA) spread is of concern in the hospital and community. Clinical medical students can serve as vectors for the transmission of the pathogen. This study was aimed to determine the level of knowledge, attitude and perception of MRSA among clinical medical students in Babcock University, Ilishan-Remo, Ogun State, Nigeria. Methods: This was a descriptive cross-sectional study that involved 100 clinical medical students in Babcock University from March 2018 to March 2019. A structured self-administered questionnaire was used to assess the knowledge, attitude and perception of MRSA among the participants. Data were analysed using IBM SPSS version 23. The mean ± standard deviation (SD) of the correct answers to knowledge, attitude and perception of MRSA was analysed, respectively. Respondents who scored more than the mean ± SD were considered to have adequate knowledge, attitude and perception. Results: Majority (59%) had respectively poor knowledge, attitude (51%) and perception (51%) about MRSA. Among the 41% who have heard about MRSA, 30/41 (73.2%) had their source of information from classroom lectures. Fifty-seven per cent of the participants did not know the drug of choice for MRSA, whereas 32% were not sure of the importance of handwashing in the prevention of MRSA. Good knowledge and perception were significantly associated with clinical year of study (P < 0.05), whereas good knowledge was significantly associated with marital status (P = 0.029) and clinical year of study (P < 0.05). Conclusion: The level of knowledge, attitude and perception of the study participants to MRSA was inadequate.

1839. Contact Precautions’ Effects on MRSA Transmission in Department of Veterans Affairs Hospitals

BackgroundIn 2007, the Department of Veterans Affairs (VA) implemented the methicillin-resistant Staphylococcus aureus (MRSA) Prevention Initiative nationally in acute care facilities (ACFs). The initiative included universal nasal surveillance for MRSA colonization and implementation of contact precautions (CP) for identified carriers for the duration of their stay. Despite subsequent declines in MRSA infection rates in the VA, debate on CP efficacy continues, due to limited and inconclusive direct evidence. This study estimated CP impact on MRSA transmission in the VA.MethodsWe analyzed 1 year of data from 36 VA ACFs in 2014 using a Bayesian transmission model. The data included admission, discharge, and surveillance and clinical test results for MRSA. Per the MRSA Prevention Initiative protocol that placed known carriers on CP, we assumed patients were on CP starting 12 hours after a positive surveillance test, 24 hours after a positive clinical culture, or at admission if the patient had a positive test within 365 days prior to admission. Our model produced estimates of ward-specific transmission rate, surveillance test sensitivity, importation probability, and the CP effect parameter (CPe). For CPe < 1, CP reduced transmission. Additionally, we combined the estimates of CPe using a random-effects model with inverse variance weights to derive pooled estimates and corresponding standard errors.ResultsFacility size varied with a median daily census of 70 patients per day (range: 44–111). During the study period, 144,386 individuals were admitted into one of 36 ACFs, for 215,207 total admissions. The median percentage of admissions requiring contact precautions was 11.0% (range: 6.4%–16.1%). The estimated CPe was less than one in each of the 36 facilities with a median of 0.43 (range: 0.25–0.68). Our pooled estimate of CPe across all facilities was 0.47 (95% CI; 0.40, 0.55).ConclusionWe found evidence of reduced MRSA transmission from patients on CP. This result was statistically significant in 5 of the 36 facilities and our pooled estimate suggests contact precautions could reduce the transmission rate by half. Further work is needed to account for imperfect compliance with CP, and for patients on CP for other reasons. Disclosures All Authors: No reported Disclosures.

Quantitative Results of a National Intervention to Prevent Hospital-Onset Methicillin-Resistant Staphylococcus aureus Bloodstream Infection: A Pre-Post Observational Study.

Methicillin-resistant Staphylococcus aureus (MRSA) remains one of the most common causes of health care-associated infection (HAI). To evaluate the effect of education and a tiered, evidence-based infection prevention strategy on rates of hospital-onset MRSA bloodstream infection (BSI). Prospective, national, nonrandomized, interventional, 12-month, multiple cohort, pre-post observational quality improvement project. Acute care, long-term acute care, and critical access hospitals with a disproportionate burden of HAI. All patients admitted to participating facilities during the project period. A multimodal infection prevention intervention consisting of recommendations and tools for prioritizing and implementing evidence-based infection prevention strategies, on-demand educational videos, Internet-based live educational presentations, and access to content experts. Rates of hospital-onset MRSA BSI, overall and stratified by hospital type, during 12-month baseline and postintervention periods. Variation in outcomes across hospital types was examined. Between November 2016 and May 2018, 387 hospitals in 23 states and the District of Columbia participated, 353 (91%) submitted MRSA data, and 172 (49%) indicated that MRSA prevention was a priority. Unadjusted overall rates of hospital-onset MRSA BSI were 0.075 (95% CI, 0.065 to 0.085) and 0.071 (CI, 0.063 to 0.080) per 1000 patient-days in the baseline and postintervention periods, respectively. The intervention period was short. Participation and adherence to recommended interventions were not fully assessed. Baseline rates of hospital-onset MRSA BSI were relatively low. Prevention of MRSA was a priority in a minority of participating hospitals. Patient characteristics and other MRSA risk factors were not assessed. In hospitals with a disproportionate burden of HAIs, access to tools to assist with implementation of evidence-based prevention strategies and education resources alone may not be sufficient to prevent MRSA BSI. Centers for Disease Control and Prevention.

Impact of decolonization on methicillin-resistant Staphylococcus aureus transmission and infection in a neonatal intensive care unit.

The value of decolonization as a strategy for preventing methicillin-resistantStaphylococcus aureus (MRSA) in the neonatal intensive care unit (NICU) remains to be determined. After adding decolonization to further reduce MRSA transmission in our NICU, we conducted this retrospective review to evaluate its effectiveness. The review included patients who were admitted to our NICU between April 2015 and June 2018 and were eligible for decolonization including twice daily intranasal mupirocin and daily chlorhexidine gluconate bathing over 5 consecutive days. Patients were considered successfully decolonized if 3 subsequent MRSA screenings conducted at 1-week intervals were negative. The MRSA acquisition rate (AR) was calculated as hospital-acquired (HA) MRSA per 1,000 patient days (PD) and was used to measure the effectiveness of the decolonization. Of the 151 MRSA patients being reviewed, 78 (51.6%) were HA-MRSA, resulting in an overall AR of 1.27 per 1,000 PD. Between April 2015 and February 2016, when only the decolonization was added, the AR was 2.38 per 1,000 PD. Between March 2016 and June 2018 after unit added a technician dedicated to the cleaning of reusable equipment, the AR decreased significantly to 0.92 per 1,000 PD (P < .05). Of the 78 patients who were started on the decolonization, 49 (62.8%) completed the protocol, 11 (14.1%) remained colonized, and 13 (16.7%) were recolonized prior to NICU discharge. In a NICU with comprehensive MRSA prevention measures in place, enhancing the cleaning of reusable equipment, not decolonization, led to significant reduction of MRSA transmission.

In-Vitro Investigation on the Antiseptic Efficacy of Commonly Used Disinfectants in Dairy Farms Against Methicillin-Resistant Staphylococcus Aureus

Concern has been rising with the respect to the capability of clinically important bacteria to acquire resistance against antibiotics and disinfectants. This investigation was undertaken to provide information on the sensitivity of methicillin-resistant Staphylococcus aureus (MRSA) to some disinfectants. The isolated PCR genotyped MRSA strains were collected from milk and its surrounding animal milking environment of 4 dairy cattle farms. Five commonly used disinfectants (quaternary ammonium compounds, iodine (Povidone-iodine), Sodium hypochlorite (Chlorine), ethyl alcohol and Chloroxylenol (Dettol) were evaluated at different contact times (5, 10, 15 minutes) and variable concentrations using suspension test for measuring their minimal inhibitory concentrations (MICs) against each isolate. The obtained results of MICs of the five tested disinfectants indicated high sensitivity of MRSA to both QACs and iodine, with MICs of 0.25% within 5 minutes(QACs), and 1.37% within 5 minutes (Iodine) at three tested concentrations and exposure times. Nonetheless, these strains exhibited a significant resistance to both ethyl alcohol and chlorine at different concentrations and contact times. Meanwhile, Dettol inhibited MRSA growth at dilutions (5% & 2.5%) within (5, 15, 20 minutes), however, 1.25% at 5 and 15 minutes was unable to potentiate the antibacterial activities of Dettol against strains tested. The findings of the present study reinforce the importance of disinfection as an integral part of the control policies of MRSA prevention and eradication in dairy farms.

Discovery of Linear Low-Cationic Peptides to Target Methicillin-Resistant Staphylococcus aureus in Vivo.

The development and rapid spread of multidrug resistant (MDR) bacteria cause severe public crises. New antibacterial compounds are urgently needed to treat bacterial infections. By circumventing the disadvantages of cationic peptides here, we engineered a short, linear, low-cationic peptide bacaucin-1a, which exhibited remarkable antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA). Bacaucin-1a was efficient in the prevention of MRSA associated infections in both in vitro and in vivo models with a unique mode of action. The discovery of low-cationic antibiotic candidates will extend our antibiotic pipeline in the fight against antibiotic resistant bacteria.

Evaluation of a novel optical assay for rapid detection of methicillin-resistant Staphylococcus aureus in liquid culture

Valid detection of methicillin-resistant Staphylococcus aureus (MRSA) is a precondition for MRSA prevention measures. Most of the available MRSA screening tests are based either on the identification of colony material grown on solid agar media or on direct molecular approaches. The HB&L MRSA KIT (Alifax, Polverara, Italy) is designed to screen for MRSA in liquid cultures applying the light scattering technology. Here, the assay was evaluated with pure culture isolates from solid agar media on a representative subset of 29 MRSA and 171 methicillin-susceptible S. aureus clinical strains from a German multicenter study reflecting the ratio of MRSA to MSSA in Germany. Additionally, 53 mecA/mecC-MRSA comprising hospital-, community and livestock-associated MRSA as well as 20 clinical coagulase-negative staphylococci (CoNS) challenge strains were tested. Including the results of the assay-immanent confirmatory tests for positively tested strains, the sensitivity, specificity and the positive and negative predictive values were 100%. The methicillin-resistance was also correctly identified for all challenge strains.

Methicillin Resistant Staphylococcus aureus in Pus samples

Methicillin Resistant Staphylococcus aureus (MRSA) is an emerging multidrug resistant bug worldwide. Knowing prevalence of MRSA is important to know for choosing empiric therapy and to screen colonized patients or staff. As Staphylococcus aureus is most common among pus samples, we have selected to do this study in this region. All clinical pus samples after receiving to Microbiology department, immediately inoculated in basal media such as Nutrient agar, Macconkey agar, Blood agar, Brain Heart Infusion Broth and selective media including mannitol salt agar DNAse agar. All Media plates after inoculation were incubated for 24 hours at 370C. Out of 136, 59 (43.3%) were Staphylococcus aureus and MRSA was 17 (28.8%). In the present study, 20.3% were staphylococcal isolates sensitive to penicillin, 45.7% were sensitive to erythromycin, 42.3% were sensitive to clindamycin, 71.1% were sensitive to cefoxitin & cotrimoxazole, 30.5% were sensitive to ciprofloxacin, 88.1% were sensitive to gentamicin, 96.6% were sensitive to linezolid and 100% isolates were sensitive to tigecycline, teicoplanin and vancomycin. Guidelines for the prevention and control of MRSA should be followed in hospital care settings. Screening of MRSA should make a definite policy on all seriously ill patients after admission.