The Control of Methicillin-Resistant Staphylococcus aureus Blood Stream Infections in England

Frequency and mortality rate following antimicrobial-resistant bloodstream infections in tertiary-care hospitals compared with secondary-care hospitals

There are few studies comparing proportion, frequency, mortality and mortality rate following antimicrobial-resistant (AMR) infections between tertiary-care hospitals (TCHs) and secondary-care hospitals (SCHs) in low and middle-income countries (LMICs) to inform intervention strategies. The aim of this study is to demonstrate the utility of an offline tool to generate AMR reports and data for a secondary data analysis. We conducted a secondary-data analysis on a retrospective, multicentre data of hospitalised patients in Thailand. Routinely collected microbiology and hospital admission data of 2012 to 2015, from 15 TCHs and 34 SCHs were analysed using the AMASS v2.0 (www.amass.website). We then compared the burden of AMR bloodstream infections (BSI) between those TCHs and SCHs. Of 19,665 patients with AMR BSI caused by pathogens under evaluation, 10,858 (55.2%) and 8,807 (44.8%) were classified as community-origin and hospital-origin BSI, respectively. The burden of AMR BSI was considerably different between TCHs and SCHs, particularly of hospital-origin AMR BSI. The frequencies of hospital-origin AMR BSI per 100,000 patient-days at risk in TCHs were about twice that in SCHs for most pathogens under evaluation (for carbapenem-resistant Acinetobacter baumannii [CRAB]: 18.6 vs. 7.0, incidence rate ratio 2.77; 95%CI 1.72-4.43, p<0.001; for carbapenem-resistant Pseudomonas aeruginosa [CRPA]: 3.8 vs. 2.0, p = 0.0073; third-generation cephalosporin resistant Escherichia coli [3GCREC]: 12.1 vs. 7.0, p<0.001; third-generation cephalosporin resistant Klebsiella pneumoniae [3GCRKP]: 12.2 vs. 5.4, p<0.001; carbapenem-resistant K. pneumoniae [CRKP]: 1.6 vs. 0.7, p = 0.045; and methicillin-resistant Staphylococcus aureus [MRSA]: 5.1 vs. 2.5, p = 0.0091). All-cause in-hospital mortality (%) following hospital-origin AMR BSI was not significantly different between TCHs and SCHs (all p>0.20). Due to the higher frequencies, all-cause in-hospital mortality rates following hospital-origin AMR BSI per 100,000 patient-days at risk were considerably higher in TCHs for most pathogens (for CRAB: 10.2 vs. 3.6,mortality rate ratio 2.77; 95%CI 1.71 to 4.48, p<0.001; CRPA: 1.6 vs. 0.8; p = 0.020; 3GCREC: 4.0 vs. 2.4, p = 0.009; 3GCRKP, 4.0 vs. 1.8, p<0.001; CRKP: 0.8 vs. 0.3, p = 0.042; and MRSA: 2.3 vs. 1.1, p = 0.023). In conclusion, the burden of AMR infections in some LMICs might differ by hospital type and size. In those countries, activities and resources for antimicrobial stewardship and infection control programs might need to be tailored based on hospital setting. The frequency and in-hospital mortality rate of hospital-origin AMR BSI are important indicators and should be routinely measured to monitor the burden of AMR in every hospital with microbiology laboratories in LMICs.

Effect of contact precautions on preventing meticillin-resistant Staphylococcus aureus transmission in intensive care units: a review and modelling study of field trials

BACKGROUND

Contact precautions (CPs) have been widely implemented in hospitals, particularly in intensive care units (ICUs), as the standard approach for managing meticillin-resistant Staphylococcus aureus (MRSA). However, the effectiveness of CPs in preventing MRSA transmission remains a subject of debate.

AIM

To assess the effectiveness of CPs in reducing MRSA transmission within ICUs.

METHODS

A comprehensive analysis was conducted using data from 16 sets of parameters collected from 13 field studies investigating the effectiveness of CPs in ICUs, and an epidemiologic model was developed to simulate the dynamics of MRSA incidence in the hospital setting.

FINDINGS

The analysis demonstrated a mean reduction of 20.52% (95% confidence interval -30.52 to 71.60%) in the MRSA transmission rate associated with the implementation of CPs. Furthermore, reducing the time-delay of screening tests and increasing the percentage of patients identified with MRSA through screening at admission were found to contribute to the effectiveness of CPs.

CONCLUSION

Proper implementation of CPs, with a particular emphasis on early identification of MRSA-colonized/infected patients, demonstrated a strong association with reduced MRSA transmission within the hospital setting. However, further research is necessary to investigate the effectiveness and safety of decolonization and other interventions used in conjunction with CPs to mitigate the risk of infection among colonized patients.

Preventing healthcare-associated MRSA bacteremia: getting to the root of the problem

Introduction

Bloodstream infections caused by methicillin-resistant Staphylococcus aureus (MRSA) remain a major challenge in most countries worldwide.

Setting

We describe a quasi-experimental sequential intervention at Mater Dei Hospital, Malta, to reduce hyper-prevalence of healthcare-associated MRSA bacteremia (HA-MRSA-B).

Interventions

The hospital initiated a hand hygiene (HH) campaign in 2008 to improve alcohol hand rub (AHR) use. In 2011, this was followed by root cause analysis (RCA) of all HA-MRSA-B cases and finally universal MRSA admission screening in 2014. Change-point analysis was used to evaluate the impact of the interventions.

Results

The effect of the HH campaign became evident when AHR consumption reached 40 L/1000 occupied bed days (BD). RCAs identified intravascular devices as the likely risk factor in 83% of all HA-MRSA-B; specifically non-tunneled double-lumen hemodialysis catheters (36%), peripheral venous cannulas (25%), and central venous catheters (22%). Interventions to improve their management resulted in the greatest reduction of HA-MRSA-B rates. They were informed by the RCA findings and targeted behavior change through education, motivation, and system change. Universal MRSA admission screening provided the final decline in incidence. Each intervention affected HA-MRSA-B rates after a lag period of approximately 18-24 months. Overall, HA-MRSA-B incidence decreased from 1.72 cases/10000BD in 2008 to 0.18/10000BD in 2019; a reduction of almost 90%. Intravenous device interventions were also associated with a reduction of methicillin-sensitive Staphylococcus aureus (MSSA) bacteremia rates.

Conclusions

Significant improvement in HA-MRSA-B is possible, even in highly endemic regions. It requires well-planned behavior change interventions which are compatible with local context and culture.

The Role of Stakeholders' Understandings in Emerging Antimicrobial Resistance: A One Health Approach

The increasing misuse of antibiotics in human and veterinary medicine and in agroecosystems and the consequent selective pressure of resistant strains lead to multidrug resistance (AMR), an expanding global phenomenon. Indeed, this phenomenon represents a major public health target with significant clinical implications related to increased morbidity and mortality and prolonged hospital stays. The current presence of microorganisms multi-resistant to antibiotics isolated in patients is a problem because of the additional burden of disease it places on the most fragile patients and the difficulty of finding effective therapies. In recent decades, international organizations like the World Health Organization (WHO) and the European Centre for Disease Prevention and Control (ECDC) have played significant roles in addressing the issue of AMR. The ECDC estimates that in the European Union alone, antibiotic resistance causes 33,000 deaths and approximately 880,000 cases of disability each year. The epidemiological impact of AMR inevitably also has direct economic consequences related not only to the loss of life but also to a reduction in the number of days worked, increased use of healthcare resources for diagnostic procedures and the use of second-line antibiotics when available. In 2015, the WHO, recognising AMR as a complex problem that can only be addressed by coordinated multi-sectoral interventions, promoted the One Health approach that considers human, animal, and environmental health in an integrated manner. In this review, the authors try to address why a collaboration of all stakeholders involved in AMR growth and management is necessary in order to achieve optimal health for people, animals, plants, and the environment, highlighting that AMR is a growing threat to human and animal health, food safety and security, economic prosperity, and ecosystems worldwide.

Alternatives to antibiotics in veterinary medicine: considerations for the management of Johne's disease

Antibiotic resistance has become a major health concern globally, with current predictions expecting deaths related to resistant infections to surpass those of cancer by 2050. Major efforts are being undertaken to develop derivative and novel alternatives to current antibiotic therapies in human medicine. What appears to be lacking however, are similar efforts into researching the application of those alternatives, such as (bacterio)phage therapy, in veterinary contexts. Agriculture is still undoubtedly the most prominent consumer of antibiotics, with up to 70% of annual antibiotic usage attributed to this sector, despite policies to reduce their use in food animals. This not only increases the risk of resistant infections spreading from farm to community but also the risk that animals may acquire species-specific infections that subvert treatment. While these diseases may not directly affect human welfare, they greatly affect the profit margin of industries reliant on livestock due to the cost of treatments and (more frequently) the losses associated with animal death. This means actively combatting animal infection not only benefits animal welfare but also global economies. In particular, targeting recurring or chronic conditions associated with certain livestock has the potential to greatly reduce financial losses. This can be achieved by developing novel diagnostics to quickly identify ill animals alongside the design of novel therapies. To explore this concept further, this review employs Johne's disease, a chronic gastroenteritis condition that affects ruminants, as a case study to exemplify the benefits of rapid diagnostics and effective treatment of chronic disease, with particular regard to the diagnostic and therapeutic potential of phage.

Evaluation of methicillin-resistant Staphylococcus aureus (MRSA) bacteremia: Epidemiology, clinical characteristics, and outcomes in the older patients in a tertiary teaching hospital in Malaysia

BACKGROUND

Methicillin-resistant Staphylococcus aureus (MRSA) bacteremia is a major concern in the global healthcare system. However, data from Asian regions dealing with the singularity of this infection in older persons is lacking. We aimed to identify the differences in the clinical characteristics and outcomes of MRSA bacteremia between adults aged 18-64 and ≥ 65 years.

METHODS

A retrospective study cohort was conducted at the University Malaya Medical Centre (UMMC) on cases of MRSA bacteremia from 2012 to 2016. Patient demographic and clinical data were collected for risk factors analyses.

RESULTS

New cases of MRSA bacteremia showed a trend of increase from 0.12 to 100 admissions in 2012 to 0.17 per 100 admissions in 2016 but a drop was observed in 2014 (0.07 per 100 admissions). Out of the 275 patients with MRSA bacteremia, 139 (50.5%) patients were aged ≥ 65 years old. Co-morbidities and severity at presentation were significantly higher among older adults, including diabetes mellitus (p = 0.035), hypertension (p = 0.001), and ischemic heart disease (p < 0.001), as well as higher Charlson Comorbidity Index (p < 0.001) and Pitt bacteremia scores (p = 0.016). Central line-associated bloodstream infections were more common among younger patients (37.5% vs. 17.3% in older patients, p < 0.001), while skin and soft tissue infections are more frequent among older adults (20.9% vs. 10.3% in younger patients, p = 0.016). All-cause mortality and in-hospital mortality were significantly higher in older patients (82.7% and 56.1% vs. 63.2% and 28.7% in younger patients, p < 0.001). Multivariate analysis revealed age ≥ 65 years (adjusted odds ratio: 3.36; 95% confidence interval: 1.24-9.13), Pitt score ≥ 3 (2.15; 1.54-3.01), hospital (6.12; 1.81-20.72) and healthcare (3.19; 1.30-7.81) acquisition of MRSA, indwelling urinary catheters (5.43; 1.39-21.23), inappropriate targeted treatment (8.08; 1.15-56.86), lack of infectious disease team consultation (2.90; 1.04-8.11) and hypoalbuminemia (3.31; 1.25-8.79), were significant risk factors for 30-day mortality.

CONCLUSION

Older patients' risk of mortality from MRSA bacteremia was three times higher than younger patients. Our data will contribute to developing and validating a robust scoring system for risk-stratifying patients to achieve better management and improved clinical outcomes.

A systematic literature review to evaluate extended dosing intervals in the pharmacological management of acromegaly

PURPOSE

This systematic literature review investigated whether extended dosing intervals (EDIs) of pharmacological acromegaly treatments reduce patient burden and costs compared with standard dosing, while maintaining effectiveness.

METHODS

MEDLINE/Embase/the Cochrane Library (2001-June 2021) and key congresses (2018-2021) were searched and identified systematic literature review bibliographies reviewed. Included publications reported on efficacy/effectiveness, safety and tolerability, health-related quality of life (HRQoL), and patient-reported and economic outcomes in longitudinal/cross-sectional studies in adults with acromegaly. Interventions included EDIs of pegvisomant, cabergoline, and somatostatin receptor ligands (SRLs): lanreotide autogel/depot (LAN), octreotide long-acting release (OCT), pasireotide long-acting release (PAS), and oral octreotide; no comparator was required.

RESULTS

In total, 35 publications reported on 27 studies: 3 pegvisomant monotherapy, 11 pegvisomant combination therapy with SRLs, 9 LAN, and 4 OCT; no studies reported on cabergoline, PAS, or oral octreotide at EDIs. Maintenance of normal insulin-like growth factor I (IGF-I) was observed in ≥ 70% of patients with LAN (1 study), OCT (1 study), and pegvisomant monotherapy (1 study). Achievement of normal IGF-I was observed in ≥ 70% of patients with LAN (3 studies) and pegvisomant in combination with SRLs (4 studies). Safety profiles were similar across EDI and standard regimens. Patients preferred and were satisfied with EDIs. HRQoL was maintained and cost savings were provided with EDIs versus standard regimens.

CONCLUSIONS

Clinical efficacy/effectiveness, safety, and HRQoL outcomes in adults with acromegaly were similar and costs lower with EDIs versus standard regimens. Physicians may consider acromegaly treatment at EDIs, especially for patients with good disease control.

Polymeric nano-system for macrophage reprogramming and intracellular MRSA eradication

Intracellular Methicillin-Resistant Staphylococcus aureus (MRSA) remains a major factor of refractory and recurrent infections, which cannot be well addressed by antibiotic therapy. Here, we design a cellular infectious microenvironment-activatable polymeric nano-system to mediate targeted intracellular drug delivery for macrophage reprogramming and intracellular MRSA eradication. The polymeric nano-system is composed of a ferrocene-decorated polymeric nanovesicle formulated from poly(ferrocenemethyl methacrylate)-block-poly(2-methacryloyloxyethyl phosphorylcholine) (PFMMA-b-PMPC) copolymer with co-encapsulation of clofazimine (CFZ) and interferon-γ (IFN-γ). The cellular-targeting PMPC motifs render specific internalization by macrophages and allow efficient intracellular accumulation. Following the internalization, the ferrocene-derived polymer backbone sequentially undergoes hydrophobic-to-hydrophilic transition, charge reversal and Fe release in response to intracellular hydrogen peroxide over-produced upon infection, eventually triggering endosomal escape and on-site cytosolic drug delivery. The released IFN-γ reverses the immunosuppressive status of infected macrophages by reprogramming anti-inflammatory M2 to pro-inflammatory M1 phenotype. Meanwhile, intracellular Fe²⁺-mediated Fenton reaction together with antibiotic CFZ contributes to increased intracellular hydroxyl radical (•OH) generation. Ultimately, the nano-system achieves robust potency in ablating intracellular MRSA and antibiotic-tolerant persisters by synchronous immune modulation and efficient •OH killing, providing an innovative train of thought for intracellular MRSA control.

Exploring the Barriers in the Uptake of the Dutch MRSA ‘Search and Destroy’ Policy Using the Cascade of Care Approach

The Dutch ‘search and destroy’ policy consists of screening patients with an increased risk of methicillin-resistant Staphylococcus aureus (MRSA) carriership and subsequent decolonization treatment when carriership is found. Decolonization therapy of individual MRSA carriers is effective. However, the effectiveness of the national ‘search and destroy’ policy is dependent on the entire cascade of care, including identification, referral, and subsequent treatment initiation in MRSA carriers. The aim of this study was to evaluate the leakages in the cascade of MRSA decolonization care. We assessed familiarity with the ‘search and destroy’ policy and the barriers in the uptake of MRSA eradication care using a questionnaire among 114 Dutch general practitioners. The main reasons for treatment were planned hospital visits, occupational reasons, and infections. The main reasons for refraining from eradication treatment were unfamiliarity with the ‘search and destroy’ policy and the assumption that MRSA carriership is often self-limiting. To optimize the continuity of the cascade of care, interventions should be aimed at supporting general practitioners and facilitating treatment and referral.

Human macrophage polarization determines bacterial persistence of Staphylococcus aureus in a liver-on-chip-based infection model

Infections with Staphylococcus aureus (S. aureus) have been reported from various organs ranging from asymptomatic colonization to severe infections and sepsis. Although considered an extracellular pathogen, S. aureus can invade and persist in professional phagocytes such as monocytes and macrophages. Its capability to persist and manipulate macrophages is considered a critical step to evade host antimicrobial reactions. We leveraged a recently established human liver-on-chip model to demonstrate that S. aureus specifically targets macrophages as essential niche facilitating bacterial persistence and phenotype switching to small colony variants (SCVs). In vitro, M2 polarization was found to favor SCV-formation and was associated with increased intracellular bacterial loads in macrophages, increased cell death, and impaired recruitment of circulating monocytes to sites of infection. These findings expand the knowledge about macrophage activation in the liver and its impact on bacterial persistence and dissemination in the course of infection.

Hospital-Onset Bloodstream Infections Caused by Eight Sentinel Bacteria: A Nationwide Study in Israel, 2018–2019

Nationwide studies on hospital-onset bloodstream infections (HO-BSIs) are scarce. To describe incidence, mortality and antimicrobial resistance (AMR) of HO-BSI caused by eight sentinel bacteria in Israel, we used laboratory-based BSI surveillance data from 1 January 2018 to 31 December 2019. All hospitals reported positive blood cultures growing Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Acinetobacter baumannii, Streptococcus pneumoniae, Staphylococcus aureus, Enterococcus faecalis and Enterococcus faecium. We calculated HO-BSI incidence and 14-day, 30-day and 1-year mortality in adults. We performed multivariable logistic regression to identify predictors of 30-day mortality. The study included 6752 HO-BSI events: K. pneumoniae (1659, 22.1%), E. coli (1491, 19.8%), S. aureus (1315, 17.5%), P. aeruginosa (1175, 15.6%), E. faecalis (778, 10.4%), A. baumannii (654, 8.7%), E. faecium (405, 5.4%) and S. pneumoniae (43, 0.6%). Overall incidence was 2.84/1000 admissions (95% CI: 2.77–2.91) and 6.88/10,000 patient-days (95% CI: 6.72–7.05). AMR isolates accounted for 44.2% of events. Fourteen-day, thirty-day and one-year mortality were 30.6% (95% CI: 28.5%–32.8%), 40.2% (95% CI: 38.2%–42.1%) and 66.5% (95% CI: 64.7%–68.3%), respectively. Organisms with highest risk for 30-day mortality (compared with E. coli) were A. baumannii (OR 2.85; 95% CI: 2.3–3.55), E. faecium (OR 2.16; 95% CI: 1.66–2.79) and S. pneumoniae (OR 2.36; 95% CI: 1.21–4.59). Mortality was higher in AMR isolates (OR 1.57; 95% CI: 1.4–1.77). This study highlights the incidence, associated high mortality and important role of antibiotic resistance in HO-BSI.

‘Superbugs’: raising public awareness of antimicrobial resistance through a pop-up science shop

‘Superbugs: A Pop-up Science Shop’ was a public engagement event in the school summer holidays of 2019, organised by members of Cardiff University’s School of Medicine. We transformed an empty retail unit in the centre of Wales’s largest shopping centre into an interactive and immersive microbiology experience. We facilitated two-way dialogue to impart positive impact on the awareness of antibiotic resistance, while concurrently evaluating the efficacy of an engagement strategy focused on the utilisation of public spaces to attract public demographics diverse to those who would normally engage with conventional science, technology, engineering and mathematics (STEM) outreach. Over the course of 14 days, we welcomed 6,566 visitors, with 67 per cent attending as part of the natural footfall of the shopping centre. We created 1,626 young Antibiotic Resistance Champions, located in over two hundred schools, across many of the most deprived areas in Wales. We imparted a positive impact to our stakeholders, with a significant increase in the knowledge and understanding of the subject of antimicrobial resistance (AMR); 91.7 per cent indicated that they had a better understanding after the event. In this article, we discuss the evolution of ‘Superbugs’ from concept, planning and design, to the logistics of delivering an engagement event of this scale. We focus in particular on the learning outcomes of the project, and on how this will shape the future of our ‘Superbugs’ project, and engagement events beyond.

Probabilistic modelling of effects of antibiotics and calendar time on transmission of healthcare-associated infection

Healthcare-associated infection and antimicrobial resistance are major concerns. However, the extent to which antibiotic exposure affects transmission and detection of infections such as MRSA is unclear. Additionally, temporal trends are typically reported in terms of changes in incidence, rather than analysing underling transmission processes. We present a data-augmented Markov chain Monte Carlo approach for inferring changing transmission parameters over time, screening test sensitivity, and the effect of antibiotics on detection and transmission. We expand a basic model to allow use of typing information when inferring sources of infections. Using simulated data, we show that the algorithms are accurate, well-calibrated and able to identify antibiotic effects in sufficiently large datasets. We apply the models to study MRSA transmission in an intensive care unit in Oxford, UK with 7924 admissions over 10 years. We find that falls in MRSA incidence over time were associated with decreases in both the number of patients admitted to the ICU colonised with MRSA and in transmission rates. In our inference model, the data were not informative about the effect of antibiotics on risk of transmission or acquisition of MRSA, a consequence of the limited number of possible transmission events in the data. Our approach has potential to be applied to a range of healthcare-associated infections and settings and could be applied to study the impact of other potential risk factors for transmission. Evidence generated could be used to direct infection control interventions.

Prevalence of methicillin-resistant Staphylococcus aureus in a tertiary hospital in Nepal

SETTING:

Patan Hospital, Lalitpur, Nepal.

OBJECTIVES:

To describe 1) the prevalence of methicillin-resistant Staphylococcus aureus (MRSA) and its antibiotic sensitivity pattern; 2) the demographic and clinical characteristics associated with MRSA infections; and 3) the treatment outcomes of in-patients with MRSA infection among patients with S. aureus infection between January 2018 and December 2020.

DESIGN:

This was a cross-sectional study using electronic and paper-based hospital records of patients with S. aureus infection.

RESULTS:

Of the 1,804 patients with S. aureus infection, 1,027 patients (57%, 95% CI 55–59) had MRSA. The MRSA were susceptible to vancomycin (100%), linezolid (96%), doxycycline (96%), chloramphenicol (86%) and cotrimoxazole (70%), and resistant to erythromycin (68%), clindamycin (56%), gentamycin (58%), ciprofloxacin (92%) and ofloxacin (91%). The prevalence of MRSA was higher in 2019, among out-patients, and in respiratory samples, and lower in blood samples. Of the 142 in-patients with MRSA, 93% had a successful clinical outcome (cured/improved).

CONCLUSION:

More than 50% of patients with S. aureus infection had MRSA that were resistant to commonly available antibiotics. This calls for strengthening surveil-lance and good infection control practices in this hospital.

Antibiotic resistance lessons for the herbicide resistance crisis

The challenges of resistance to antibiotics and resistance to herbicides have much in common. Antibiotic resistance became a risk in the 1950s, but a concerted global effort to manage it did not begin until after 2000. Widespread herbicide use began during the 1950s and was soon followed by an unabated rise in resistance. Here, we examine what lessons for combatting herbicide resistance could be learnt from the global, coordinated efforts of all stakeholders to avert the antibiotic resistance crisis. © 2021 Society of Chemical Industry.

Are resistance rates among bloodstream isolates a good proxy for other infections? Analysis from the BSAC Resistance Surveillance Programme

BACKGROUND

Bacteraemia data are often used as a general measure of resistance prevalence but may poorly represent other infection types. We compared resistance prevalence between bloodstream infection (BSI) and lower respiratory tract infection (LRTI) isolates collected by the BSAC Resistance Surveillance Programme.

METHODS

BSI isolates (n = 8912) were collected during 2014-18 inclusive and LRTI isolates (n = 6280) between October 2013 to September 2018 from participating laboratories in the UK and Ireland, to a fixed annual quota per species group. LRTI isolates, but not BSI, were selected by onset: community for Streptococcus pneumoniae; hospital for Staphylococcus aureus, Pseudomonas aeruginosa and Enterobacterales. MICs were determined centrally by agar dilution; statistical modelling adjusted for ICU location and possible clustering by collection centre.

RESULTS

Resistance was more prevalent among the LRTI isolates, even after adjusting for a larger proportion of ICU patients. LRTI P. aeruginosa and S. pneumoniae were more often resistant than BSI isolates for most antibiotics, and the proportion of MRSA was higher in LRTI. For S. pneumoniae, the observation reflected different serotype distributions in LRTI and BSI. Relationships between LRTI and resistance were less marked for Enterobacterales, but LRTI E. coli were more often resistant to β-lactams, particularly penicillin/β-lactamase inhibitor combinations, and LRTI K. pneumoniae to piperacillin/tazobactam. For E. cloacae there was a weak association between LRTI, production of AmpC enzymes and cephalosporin resistance.

CONCLUSIONS

Estimates of resistance prevalence based upon bloodstream isolates underestimate the extent of the problem in respiratory isolates, particularly for P. aeruginosa, S. pneumoniae, S. aureus and, less so, for Enterobacterales.

High Prevalence of Methicillin-Resistant Staphylococcus aureus among Healthcare Facilities and Its Related Factors in Myanmar (2018-2019)

BACKGROUND

Antimicrobial resistance (AMR) is a growing global health problem. Staphylococcus aureus (SA) is a common bacterium associated with a variety of community and hospital infections. Methicillin-resistant Staphylococcus aureus (MRSA) accounts for most SA related morbidity and mortality. In this study, we determined the prevalence and factors associated with SA and MRSA in Myanmar.

METHODS

We collected the data retrospectively by reviewing an electronic register containing the results of bacterial culture and antibiotic susceptibility testing of biological specimens received from healthcare facilities during 2018-2019.

RESULTS

Of the 37,798 biological specimens with bacterial culture growth, 22% (8244) were Gram-positive. Among the Gram-positive bacteria, 42% (2801) were SA, of which 48% (1331) were judged as MRSA by phenotypic methods. The prevalence of MRSA was higher in the older age groups, in female patients, in urine specimens and specimens received from the intensive care unit and dermatology departments. One site (Site F) had the highest MRSA prevalence of the seven AMR sentinel sites. Most SA isolates were sensitive to vancomycin (90%) by phenotypic methods.

CONCLUSIONS

The high prevalence of MRSA indicates a major public health threat. There is an urgent need to strengthen the AMR surveillance and hospital infection control program in Myanmar.

Universal admission screening: a potential game-changer in hospitals with high prevalence of MRSA

INTRODUCTION

Despite the perception that meticillin-resistant Staphylococcus aureus (MRSA) is now under control in high-income countries, global prevalence remains high, even increasing in some regions. Universal admission screening and decolonization has been instituted in some hospitals to attempt control but the practice remains controversial.

METHODS

In 2014, Mater Dei Hospital in Malta introduced a universal admission screening policy, utilizing a novel, centralized and customized approach to achieve high compliance and low cost. Admissions are screened nasally by designated staff using chromogenic media, irrespective of risk factors. Carriers are decolonized without concurrent isolation or contact precautions. In this study, longitudinal, quasi-experimental evaluation was undertaken using time series analysis to analyse the impact of the intervention on the proportion of MRSA among clinical S. aureus isolates (%MRSA) and incidence per 1000 bed-days. A cost-utility analysis was also attempted to identify approximate quality-adjusted life years (QALYs) gained.

RESULTS

A transfer function model approach concluded that the intervention had a significant effect on both %MRSA and incidence. Six years following its introduction, the screening programme had led to an overall 43% long-term reduction in %MRSA from pre-screening levels [R²=0.687; Bayesian information criterion (BIC)=4.063], translating to a decrease in incidence of approximately 0.56 cases/1000 bed-days (R²=0.633, BIC=-3.063). No correlation was identified with consumption of antibiotics or alcohol hand rub. The annual cost-benefit of the programme was calculated at €1058 per QALY gain per year.

CONCLUSION

The universal admission screening and decolonization intervention was successful and cost-effective in this high-endemicity setting. It facilitated improvement in the prevalence of MRSA, achieving reduction levels rarely reported by Mediterranean hospitals.

Treatment of methicillin-resistant Staphylococcus aureus (MRSA): updated guidelines from the UK

These evidence-based guidelines are an updated version of those issued in 2008. They have been produced following a review of the published literature (2007-18) pertaining to the treatment of infections caused by MRSA. The guidelines update, where appropriate, previous recommendations, taking into account changes in the UK epidemiology of MRSA, ongoing national surveillance data and the efficacy of novel anti-staphylococcal agents licensed for use in the UK. Emerging therapies that have not been licensed for use in the UK at the time of the review have also been assessed.

D-Serine inhibits the attachment and biofilm formation of methicillin-resistant Staphylococcus aureus

INTRODUCTION

Although therapeutic agents for methicillin-resistant Staphylococcus aureus (MRSA) are clinically available, MRSA infection is still a life-threatening disease. Bacterial attachment and biofilm formation contribute significantly to the initiation of MRSA infection. Controlling MRSA's attachment and biofilm formation might reduce the frequency of MRSA infection. According to recent data, some amino acids can reduce MRSA's attachment on plates; however, their precise inhibitory mechanisms remain unclear. Therefore, we explored the effect of the amino acids on bacterial adhesion and biofilm formation in vitro and in vivo MRSA infection models.

METHODS

We tested the inhibitory effect of amino acids on MRSA and Escherichia coli (E. coli) in the attachment assay. Moreover, we evaluated the therapeutic potential of amino acids on the in vivo catheter infection model.

RESULTS

Among the amino acids, D-Serine (D-Ser) was found to reduce MRSA's ability to attach on plate assay. The proliferation of MRSA was not affected by the addition of D-Ser; thus, D-Ser likely only played a role in preventing attachment and biofilm formation. Then, we analyzed the expression of genes related to attachment and biofilm formation. D-Ser was found to reduce the expressions of AgrA, SarS, IcaA, DltD, and SdrD. Moreover, the polyvinyl chloride catheters treated with D-Ser had fewer MRSA colonies. D-Ser treatment also reduced the severity of infection in the catheter-induced peritonitis model. Moreover, D-Ser reduced the attachment ability of E. coli.

CONCLUSION

D-Ser inhibits the attachment and biofilm formation of MRSA by reducing the expression of the related genes. Also, the administration of D-Ser reduces the severity of catheter infection in the mouse model. Therefore, D-Ser may be a promising therapeutic option for MRSA as well as E. coli infection.

Methicillin-resistant Staphylococcus aureus in hip fracture

AIMS

Infection after surgery increases treatment costs and is associated with increased mortality. Hip fracture patients have historically had high rates of methicillin-resistant Staphylococcus aureus (MRSA) colonization and surgical site infection (SSI). This paper reports the impact of routine MRSA screening and the "cleanyourhands" campaign on rates of MRSA SSI and patient outcome.

METHODS

A total of 13,503 patients who presented with a hip fracture over 17 years formed the study population. Multivariable logistic regression was performed to determine risk factors for MRSA and SSI. Autoregressive integrated moving average (ARIMA) modelling adjusted for temporal trends in rates of MRSA. Kaplan-Meier estimators were generated to assess for changes in mortality.

RESULTS

In all, 6,189 patients were identified before the introduction of screening and 7,314 in the post-screening cohort. MRSA infection fell from 69 cases to 15 in the post-screening cohort (p < 0.001). The ARIMA confirmed a significant reduction in MRSA SSI post-screening (p = 0.043) but no significant impact after hand hygiene alone (p = 0.121). Overall SSI fell (2.4% to 1.5%), however deep infection increased slightly (0.89% to 1.06%). ARIMA showed neither intervention affected overall SSI ("cleanyourhands" -0.172% (95% confidence interval (CI) -0.39% to 0.21); p = 0.122, screening -0.113% per year, (95% CI -0.34 to 0.12); p = 0.373). One-year mortality after deep SSI was unchanged after screening (50% vs 45%; p = 0.415). Only warfarinization (OR 3.616 (95% CI 1.366 to 9.569); p = 0.010) and screening (OR 0.189 (95% CI 0.086 to 0.414); p < 0.001) were significant covariables for developing MRSA SSI.

CONCLUSION

While screening and decolonization may reduce MRSA-associated SSI, the benefit to patient outcome remains unclear. Overall deep SSI remains an unsolved problem that has seen little improvement over time. Preventing other hospital-associated infections should not be forgotten in the fight against MRSA. Cite this article: Bone Joint J 2021;103-B(1):170-177.

What Is Driving the Epidemiology of Methicillin-Resistant Staphylococcus aureus Infections in Europe?

Introduction: The burden from infections caused by methicillin-resistant Staphylococcus aureus (MRSA) in the European Union/European Economic Area (EU/EEA) has increased in recent years, especially in the higher prevalence southern and eastern countries. Addressing this challenge requires a clear knowledge of the factors driving this epidemiology to inform effective national interventions and campaigns. Methods: We identified national quality metrics for antibiotic use and hand hygiene from the 2016/2017 European Centre for Disease Control (ECDC) Point Prevalence study as well as structural, cultural, and governance indicators from other sources. We then utilized general linear modeling to identify parsimonious correlations with national MRSA proportions reported by the European Antimicrobial Resistance Surveillance Network (EARS-Net). Results: The main process predictor of MRSA prevalence in EU/EEA countries was the use of more than one concurrent antibiotic per patient. The impact of hand hygiene was less clear, possibly because consumption of alcohol hand-rub was suboptimal throughout Europe. Hospital and infection control structural factors did not appear relevant at overall national level. Culture and governance were collectively key predictor groups; uncertainty avoidance, masculinity, and corruption indices strongly correlated with MRSA prevalence. Discussion: Our results suggest that the critical antibiotic stewardship factor associated with MRSA in EU/EEA countries is the quality of antibiotic prescribing, especially spectrum of activity, rather than overall consumption levels in hospitals or proportion of patients treated. Above all, MRSA hyperendemicity is correlated with a set of sociocultural behavioral constructs that typically manifest themselves in lack of urgency to address risk and normalization of deviance in relation to noncompliant practices.

Prospective genomic surveillance of methicillin-resistant Staphylococcus aureus (MRSA) associated with bloodstream infection, England, 1 October 2012 to 30 September 2013

BackgroundMandatory reporting of methicillin-resistant Staphylococcus aureus (MRSA) bloodstream infections (BSI) has occurred in England for over 15years. Epidemiological information is recorded, but routine collection of isolates for characterisation has not been routinely undertaken. Ongoing developments in whole-genome sequencing (WGS) have demonstrated its value in outbreak investigations and for determining the spread of antimicrobial resistance and bacterial population structure. Benefits of adding genomics to routine epidemiological MRSA surveillance are unknown.AimTo determine feasibility and potential utility of adding genomics to epidemiological surveillance of MRSA.MethodsWe conducted an epidemiological and genomic survey of MRSA BSI in England over a 1-year period (1 October 2012--30 September 2013).ResultsDuring the study period, 903 cases of MRSA BSI were reported; 425 isolates were available for sequencing of which, 276 (65%) were clonal complex (CC) 22. Addition of 64 MRSA genomes from published outbreak investigations showed that the study genomes could provide context for outbreak isolates and supported cluster identification. Comparison to other MRSA genome collections demonstrated variation in clonal diversity achieved through different sampling strategies and identified potentially high-risk clones e.g. USA300 and local expansion of CC5 MRSA in South West England.ConclusionsWe demonstrate the potential utility of combined epidemiological and genomic MRSA BSI surveillance to determine the national population structure of MRSA, contextualise previous MRSA outbreaks, and detect potentially high-risk lineages. These findings support the integration of epidemiological and genomic surveillance for MRSA BSI as a step towards a comprehensive surveillance programme in England.

Antimicrobial Resistance in ESKAPE Pathogens

Antimicrobial-resistant ESKAPE ( Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter species) pathogens represent a global threat to human health. The acquisition of antimicrobial resistance genes by ESKAPE pathogens has reduced the treatment options for serious infections, increased the burden of disease, and increased death rates due to treatment failure and requires a coordinated global response for antimicrobial resistance surveillance. This looming health threat has restimulated interest in the development of new antimicrobial therapies, has demanded the need for better patient care, and has facilitated heightened governance over stewardship practices.

Antimicrobial Resistance in ESKAPE Pathogens

Antimicrobial-resistant ESKAPE ( Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter species) pathogens represent a global threat to human health. The acquisition of antimicrobial resistance genes by ESKAPE pathogens has reduced the treatment options for serious infections, increased the burden of disease, and increased death rates due to treatment failure and requires a coordinated global response for antimicrobial resistance surveillance. This looming health threat has restimulated interest in the development of new antimicrobial therapies, has demanded the need for better patient care, and has facilitated heightened governance over stewardship practices.

Effectiveness of an antifungal stewardship programme at a London teaching hospital 2010-16

Background

The need for antifungal stewardship is gaining recognition with increasing incidence of invasive fungal infection (IFI) and antifungal resistance alongside the high cost of antifungal drugs. Following an audit showing suboptimal practice we initiated an antifungal stewardship programme and prospectively evaluated its impact on clinical and financial outcomes.

Patients and methods

From October 2010 to September 2016, adult inpatients receiving amphotericin B, echinocandins, intravenous fluconazole, flucytosine or voriconazole were reviewed weekly by an infectious diseases consultant and antimicrobial pharmacist. Demographics, diagnosis by European Organization for Research and Treatment of Cancer (EORTC) criteria, drug, indication, advice, acceptance and in-hospital mortality were recorded. Antifungal consumption and expenditure, and candidaemia species and susceptibility data were extracted from pharmacy and microbiology databases.

Results

A total of 432 patients were reviewed, most commonly receiving AmBisome® (35%) or intravenous fluconazole (29%). Empirical treatment was often unnecessary, with 82% having no evidence of IFI. Advice was given in 64% of reviews (most commonly de-escalating or stopping treatment) and was followed in 84%. Annual antifungal expenditure initially reduced by 30% (£0.98 million to £0.73 million), then increased to 20% above baseline over a 5 year period; this was a significantly lower rise compared with national figures, which showed a doubling of expenditure over the same period. Inpatient mortality, Candida species distribution and rates of resistance were not adversely affected by the intervention.

Conclusions

Provision of specialist input to optimize antifungal prescribing resulted in significant cost savings without compromising on microbiological or clinical outcomes. Our model is readily implementable by hospitals with high numbers of at-risk patients and antifungal expenditure.

Antimicrobial stewardship programs; a two-part narrative review of step-wise design and issues of controversy Part I: step-wise design of an antimicrobial stewardship program

Regardless of one's opinion of antimicrobial stewardship programs (ASPs), it is hardly possible to work in hospital care and not be exposed to the term or its practical effects. Despite the term being relatively new, the number of publications in the field is vast, including several excellent reviews of general and specific aspects. Work in antimicrobial stewardship is complex, and includes not only aspects of infectious disease and microbiology, but also of epidemiology, genetics, behavioural psychology, systems science, economics and ethics, to name a few. This review aims to take several of these aspects and the scientific evidence of antimicrobial stewardship studies and merge them into two questions: How should we design ASPs based on what we know today? And which are the most essential unanswered questions regarding antimicrobial stewardship on a broader scale? This narrative review is written in two separate parts aiming to provide answers to the two questions. This first part is written as a step-wise approach to designing a stewardship intervention based on the pillars of unmet need, feasibility, scientific evidence and necessary core elements. It is written mainly as a guide to someone new to the field. It is sorted into five distinct steps: (a) focusing on designing aims; (b) assessing performance and local barriers to rational antimicrobial use; (c) deciding on intervention technique; (d) practical, tailored design including core element inclusion; and (e) evaluation and sustainability. The second part, published separately, formulates ten critical questions on controversies in the field of antimicrobial stewardship. It is aimed at clinicians and researchers with stewardship experience and strives to promote discussion, not to provide answers.

Mandatory surveillance and outbreaks reporting of the WHO priority pathogens for research & discovery of new antibiotics in European countries

OBJECTIVES

In 2017 the WHO published a global priority list of 12 antibiotic-resistant bacteria (ARB) in urgent need of new antibiotics. We aimed to identify and assess publicly accessible mandatory surveillance systems and outbreaks reporting for these pathogens in the 28 European Union and four European Free Trade Association member states.

METHODS

Compulsory reporting was mapped by reviewing national documents without applying language restrictions and through expert consultation. Information on surveillance targets, indicators, metrics and dissemination modalities was extracted and a qualitative assessment was performed for open access systems only.

RESULTS

Twenty-one countries (66%) had a mandate to survey at least one among the 12 WHO priority pathogens; 15 provided access to surveillance frameworks. These systems covered most frequently carbapenem-resistant Enterobacteriales (12; 38%), methicillin-resistant Staphylococcus aureus (12; 38%), and vancomycin-resistant enterococci (8; 25%). None of the European countries required reporting of resistance in Salmonella, Campylobacter, Helicobacter pylori and Neisseria gonorrhoeae. High heterogeneity was observed in data collection, reporting and dissemination among countries with clinical outcomes and risk factors being reported in less than half (22% and 25%). Only six countries (19%) implemented mandatory surveillance of outbreaks due to at least one WHO priority pathogen.

CONCLUSIONS

Our review shows that despite the increasing burden of ARB on the European population, very few countries implemented mandatory surveillance and outbreak reporting of the WHO priority pathogens. International efforts are needed to define the effectiveness of implementing mandatory reporting of these pathogens and to assess their role in reducing the spread of ARB in health-care and community settings.

Frequent Undetected Ward-Based Methicillin-Resistant Staphylococcus aureus Transmission Linked to Patient Sharing Between Hospitals

Background

Recent evidence suggests that hospital transmission of methicillin-resistant Staphylococcus aureus (MRSA) is uncommon in UK centers that have implemented sustained infection control programs. We investigated whether a healthcare-network analysis could shed light on transmission paths currently sustaining MRSA levels in UK hospitals.

Methods

A cross-sectional observational study was performed in 2 National Health Service hospital groups and a general district hospital in Southeast London. All MRSA patients identified at inpatient, outpatient, and community settings between 1 November 2011 and 29 February 2012 were included. We identified genetically defined MRSA transmission clusters in individual hospitals and across the healthcare network, and examined genetic differentiation of sequence type (ST) 22 MRSA isolates within and between hospitals and inpatient or outpatient and community settings, as informed by average and median pairwise single-nucleotide polymorphisms (SNPs) and SNP-based proportions of nearly identical isolates.

Results

Two hundred forty-eight of 610 (40.7%) MRSA patients were linked in 90 transmission clusters, of which 27 spanned multiple hospitals. Analysis of a large 32 patient ST22-MRSA cluster showed that 26 of 32 patients (81.3%) had multiple contacts with one another during ward stays at any hospital. No residential, outpatient, or significant community healthcare contacts were identified. Genetic differentiation between ST22 MRSA inpatient isolates from different hospitals was less than between inpatient isolates from the same hospitals (P ≤ .01).

Conclusions

There is evidence of frequent ward-based transmission of MRSA brought about by frequent patient admissions to multiple hospitals. Limiting in-ward transmission requires sharing of MRSA status data between hospitals.

Strategies to reduce non-ventilator-associated hospital-acquired pneumonia: A systematic review

BACKGROUND

Point prevalence studies identify that pneumonia is the most common healthcare associated infection. However, non-ventilator associated healthcare associated pneumonia (NV-HAP) is both underreported and understudied. Most research conducted to date, focuses on ventilator associated pneumonia. We conducted a systematic review, to provide the latest evidence for strategies to reduce NV-HAP and describe the methodological approaches used.

METHODS

We performed a systematic search to identify research exploring and evaluating NV-HAP preventive measures in hospitals and aged-care facilities. The electronic database Medline was searched, for peer-reviewed articles published between 1st January 1998 and 31st August 2018. An assessment of the study quality and risk of bias of included articles was conducted using the Newcastle-Ottawa Scale.

RESULTS

The literature search yielded 1551 articles, with 15 articles meeting the inclusion criteria. The majority of strategies for NV-HAP prevention focussed on oral care (n = 9). Three studies evaluated a form of physical activity, such as passive movements, two studies used dysphagia screening and management; and another study evaluated prophylactic antibiotics. Most studies (n = 12) were conducted in a hospital setting. Six of the fifteen studies were randomised controlled trials.

CONCLUSION

There was considerable heterogeneity in the included studies, including the type of intervention, study design, methods and definitions used to diagnose the NV-HAP. To date, interventions to reduce NV-HAP appear to be based broadly on the themes of improving oral care, increased mobility or movement and dysphagia management.

Adjunctive rifampicin to reduce early mortality from Staphylococcus aureus bacteraemia: the ARREST RCT

BACKGROUND

Staphylococcus aureus bacteraemia is a common and frequently fatal infection. Adjunctive rifampicin may enhance early S. aureus killing, sterilise infected foci and blood faster, and thereby reduce the risk of dissemination, metastatic infection and death.

OBJECTIVES

To determine whether or not adjunctive rifampicin reduces bacteriological (microbiologically confirmed) failure/recurrence or death through 12 weeks from randomisation. Secondary objectives included evaluating the impact of rifampicin on all-cause mortality, clinically defined failure/recurrence or death, toxicity, resistance emergence, and duration of bacteraemia; and assessing the cost-effectiveness of rifampicin.

DESIGN

Parallel-group, randomised (1 : 1), blinded, placebo-controlled multicentre trial.

SETTING

UK NHS trust hospitals.

PARTICIPANTS

Adult inpatients (≥ 18 years) with meticillin-resistant or susceptible S. aureus grown from one or more blood cultures, who had received < 96 hours of antibiotic therapy for the current infection, and without contraindications to rifampicin.

INTERVENTIONS

Adjunctive rifampicin (600-900 mg/day, oral or intravenous) or placebo for 14 days in addition to standard antibiotic therapy. Investigators and patients were blinded to trial treatment. Follow-up was for 12 weeks (assessments at 3, 7, 10 and 14 days, weekly until discharge and final assessment at 12 weeks post randomisation).

MAIN OUTCOME MEASURES

The primary outcome was all-cause bacteriological (microbiologically confirmed) failure/recurrence or death through 12 weeks from randomisation.

RESULTS

Between December 2012 and October 2016, 758 eligible participants from 29 UK hospitals were randomised: 370 to rifampicin and 388 to placebo. The median age was 65 years [interquartile range (IQR) 50-76 years]. A total of 485 (64.0%) infections were community acquired and 132 (17.4%) were nosocomial; 47 (6.2%) were caused by meticillin-resistant S. aureus. A total of 301 (39.7%) participants had an initial deep infection focus. Standard antibiotics were given for a median of 29 days (IQR 18-45 days) and 619 (81.7%) participants received flucloxacillin. By 12 weeks, 62 out of 370 (16.8%) patients taking rifampicin versus 71 out of 388 (18.3%) participants taking the placebo experienced bacteriological (microbiologically confirmed) failure/recurrence or died [absolute risk difference -1.4%, 95% confidence interval (CI) -7.0% to 4.3%; hazard ratio 0.96, 95% CI 0.68 to 1.35; p = 0.81]. There were 4 (1.1%) and 5 (1.3%) bacteriological failures (p = 0.82) in the rifampicin and placebo groups, respectively. There were 3 (0.8%) versus 16 (4.1%) bacteriological recurrences (p = 0.01), and 55 (14.9%) versus 50 (12.9%) deaths without bacteriological failure/recurrence (p = 0.30) in the rifampicin and placebo groups, respectively. Over 12 weeks, there was no evidence of differences in clinically defined failure/recurrence/death (p = 0.84), all-cause mortality (p = 0.60), serious (p = 0.17) or grade 3/4 (p = 0.36) adverse events (AEs). However, 63 (17.0%) participants in the rifampicin group versus 39 (10.1%) participants in the placebo group experienced antibiotic or trial drug-modifying AEs (p = 0.004), and 24 (6.5%) participants in the rifampicin group versus 6 (1.5%) participants in the placebo group experienced drug-interactions (p = 0.0005). Evaluation of the costs and health-related quality-of-life impacts revealed that an episode of S. aureus bacteraemia costs an average of £12,197 over 12 weeks. Rifampicin was estimated to save 10% of episode costs (p = 0.14). After adjustment, the effect of rifampicin on total quality-adjusted life-years (QALYs) was positive (0.004 QALYs), but not statistically significant (standard error 0.004 QALYs).

CONCLUSIONS

Adjunctive rifampicin provided no overall benefit over standard antibiotic therapy in adults with S. aureus bacteraemia.

FUTURE WORK

Given the substantial mortality, other antibiotic combinations or improved source management should be investigated.

TRIAL REGISTRATIONS

Current Controlled Trials ISRCTN37666216, EudraCT 2012-000344-10 and Clinical Trials Authorisation 00316/0243/001.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 22, No. 59. See the NIHR Journals Library website for further project information.

Health care-associated infections - an overview

Health care-associated infections (HCAIs) are infections that occur while receiving health care, developed in a hospital or other health care facility that first appear 48 hours or more after hospital admission, or within 30 days after having received health care. Multiple studies indicate that the common types of adverse events affecting hospitalized patients are adverse drug events, HCAIs, and surgical complications. The US Center for Disease Control and Prevention identifies that nearly 1.7 million hospitalized patients annually acquire HCAIs while being treated for other health issues and that more than 98,000 patients (one in 17) die due to these. Several studies suggest that simple infection-control procedures such as cleaning hands with an alcohol-based hand rub can help prevent HCAIs and save lives, reduce morbidity, and minimize health care costs. Routine educational interventions for health care professionals can help change their hand-washing practices to prevent the spread of infection. In support of this, the WHO has produced guidelines to promote hand-washing practices among member countries.

Fitting the message to the location: engaging adults with antimicrobial resistance in a World War 2 air raid shelter

AIMS

There are many different initiatives, global and local, designed to raise awareness of antimicrobial resistance (AMR) and change audience behaviour. However, it is not possible to assess the impact of specific, small-scale events on national and international outcomes-although one might acknowledge some contribution to the individual and collective knowledge and experience-focused 'science capital' As with any research, in preparation for a public engagement event, it is important to identify aims, and appropriate methods whose results might help satisfy those aims. Therefore, the aim of this paper was to develop, deliver and evaluate an event designed to engage an adult audience with AMR.

METHODS AND RESULTS

The venue was a World War 2 air raid shelter, enabling comparison of the pre- and postantibiotic eras via three different activity stations, focusing on nursing, the search for new antibiotics and investigations into novel antimicrobials. The use of observers released the presenters from evaluation duties, enabling them to focus on their specific activities. Qualitative measures of audience engagement were combined with quantitative data.

CONCLUSIONS

The evaluation revealed that adult audiences can easily be absorbed into an activity-particularly if hands-on-after a brief introduction.

SIGNIFICANCE AND IMPACT OF THE STUDY

This research demonstrates that hands-on practical engagement with AMR can enable high-level interaction and learning in an informal and enjoyable environment.

Incidence of methicillin resistant Staphylococcus aureus (MRSA) in burn intensive care unit: a systematic review

Background

Burn victims admitted in burn intensive care units (ICU) are at a high risk of nosocomial infections generated by methicillin resistant Staphylococcus aureus (MRSA). This systematic review aims to estimate the incidence of MRSA among burn patients admitted to the ICU setting, with an emphasis on the incidence rate and antibiotic resistance profile of the MRSA strains.

Methods

A systematic literature search was performed in five electronic databases limited to publication dates from 1^st January 2000 until 31^st August 2017. After screening n=481 articles, n=21 were found to meet the inclusion criteria of this systematic review.

Results

Results from the meta-analysis revealed that the risk for MRSA isolates in the burn ICU was 55.0% higher (OR 0.55, 95%CI 0.32-0.94). Therefore, timely testing, appropriate hygiene practice and suggested wound care must be practiced while handling such patients.

Conclusion

Further studies are needed to identify the risk factors of MRSA infections among burn patients and to develop new antimicrobial agents for MRSA infections.

Trends over time in Escherichia coli bloodstream infections, urinary tract infections, and antibiotic susceptibilities in Oxfordshire, UK, 1998-2016: a study of electronic health records

BACKGROUND

Escherichia coli bloodstream infections are increasing in the UK and internationally. The evidence base to guide interventions against this major public health concern is small. We aimed to investigate possible drivers of changes in the incidence of E coli bloodstream infection and antibiotic susceptibilities in Oxfordshire, UK, over the past two decades, while stratifying for time since hospital exposure.

METHODS

In this observational study, we used all available data on E coli bloodstream infections and E coli urinary tract infections (UTIs) from one UK region (Oxfordshire) using anonymised linked microbiological data and hospital electronic health records from the Infections in Oxfordshire Research Database (IORD). We estimated the incidence of infections across a two decade period and the annual incidence rate ratio (aIRR) in 2016. We modelled the data using negative binomial regression on the basis of microbiological, clinical, and health-care-exposure risk factors. We investigated infection severity, 30-day all-cause mortality, and community and hospital amoxicillin plus clavulanic acid (co-amoxiclav) use to estimate changes in bacterial virulence and the effect of antimicrobial resistance on incidence.

FINDINGS

From Jan 1, 1998, to Dec 31, 2016, 5706 E coli bloodstream infections occurred in 5215 patients, and 228 376 E coli UTIs occurred in 137 075 patients. 1365 (24%) E coli bloodstream infections were nosocomial (onset >48 h after hospital admission), 1132 (20%) were quasi-nosocomial (≤30 days after discharge), 1346 (24%) were quasi-community (31-365 days after discharge), and 1863 (33%) were community (>365 days after hospital discharge). The overall incidence increased year on year (aIRR 1·06, 95% CI 1·05-1·06). In 2016, 212 (41%) of 515 E coli bloodstream infections and 3921 (28%) of 13 792 E coli UTIs were co-amoxiclav resistant. Increases in E coli bloodstream infections were driven by increases in community (aIRR 1·10, 95% CI 1·07-1·13; p<0·0001) and quasi-community (aIRR 1·08, 1·07-1·10; p<0·0001) cases. 30-day mortality associated with E coli bloodstream infection decreased over time in the nosocomial (adjusted rate ratio [RR] 0·98, 95% CI 0·96-1·00; p=0·03) group, and remained stable in the quasi-nosocomial (adjusted RR 0·98, 0·95-1·00; p=0·06), quasi-community (adjusted RR 0·99, 0·96-1·01; p=0·32), and community (adjusted RR 0·99, 0·96-1·01; p=0·21) groups. Mortality was, however, substantial at 14-25% across all hospital-exposure groups. Co-amoxiclav-resistant E coli bloodstream infections increased in all groups across the study period (by 11-18% per year, significantly faster than co-amoxiclav-susceptible E coli bloodstream infections; p_{heterogeneity}<0·0001), as did co-amoxiclav-resistant E coli UTIs (by 14-29% per year; p_{heterogeneity}<0·0001). Previous year co-amoxiclav use in primary-care facilities was associated with increased subsequent year community co-amoxiclav-resistant E coli UTIs (p=0·003).

INTERPRETATION

Increases in E coli bloodstream infections in Oxfordshire are primarily community associated, with substantial co-amoxiclav resistance; nevertheless, we found little or no change in mortality. Focusing interventions on primary care facilities, particularly those with high co-amoxiclav use, could be effective in reducing the incidence of co-amoxiclav-resistant E coli bloodstream infections, in this region and more generally.

FUNDING

National Institute for Health Research.

Laboratory data as a quality indicator of health-care-associated infections in England

Routine diagnostic laboratory results, e.g. numbers of meticillin-resistant Staphylococcus aureus (MRSA) bacteraemias, have been used as health-care-associated infection quality indicators for decades. The English health-care-associated infection quality indicator system was one of the earliest in the world to mandate the collection and public reporting of such data and has been associated with a reduction of MRSA bacteraemias and Clostridium difficile infections but has shown mixed results for other infections. Diagnostic laboratory data vary greatly between hospitals depending not only on the underlying frequency of the infection of interest, but on the case mix, numbers of samples processed and laboratory factors, which limits benchmarking. Further, over-reliance on laboratory reports has led to unintended negative consequences in England. So, while acknowledging the successes of the English system, the authors believe that it should be appraised in light of the goals of quality of care, patient safety, fairness and providing meaningful data, and alternative healthcare-associated infection quality indicator measurements considered.

Methicillin-resistant Staphylococcus aureus

Since the 1960s, methicillin-resistant Staphylococcus aureus (MRSA) has emerged, disseminated globally and become a leading cause of bacterial infections in both health-care and community settings. However, there is marked geographical variation in MRSA burden owing to several factors, including differences in local infection control practices and pathogen-specific characteristics of the circulating clones. Different MRSA clones have resulted from the independent acquisition of staphylococcal cassette chromosome mec (SCCmec), which contains genes encoding proteins that render the bacterium resistant to most β-lactam antibiotics (such as methicillin), by several S. aureus clones. The success of MRSA is a consequence of the extensive arsenal of virulence factors produced by S. aureus combined with β-lactam resistance and, for most clones, resistance to other antibiotic classes. Clinical manifestations of MRSA range from asymptomatic colonization of the nasal mucosa to mild skin and soft tissue infections to fulminant invasive disease with high mortality. Although treatment options for MRSA are limited, several new antimicrobials are under development. An understanding of colonization dynamics, routes of transmission, risk factors for progression to infection and conditions that promote the emergence of resistance will enable optimization of strategies to effectively control MRSA. Vaccine candidates are also under development and could become an effective prevention measure.

Regional Epidemiology of Methicillin-Resistant Staphylococcus aureus Among Adult Intensive Care Unit Patients Following State-Mandated Active Surveillance

Background

In 2007, Illinois became the first state in the United States to mandate active surveillance of methicillin-resistant Staphylococcus aureus (MRSA). The Illinois law applies to intensive care unit (ICU) patients; contact precautions are required for patients found to be MRSA colonized. However, the effectiveness of a legislated "search and isolate" approach to reduce MRSA burden among critically ill patients is uncertain. We evaluated whether the prevalence of MRSA colonization declined in the 5 years after the start of mandatory active surveillance.

Methods

All hospitals with an ICU having ≥10 beds in Chicago, Illinois, were eligible to participate in single-day serial point prevalence surveys. We assessed MRSA colonization among adult ICU patients present at time of survey using nasal and inguinal swab cultures. The primary outcome was region-wide MRSA colonization prevalence over time.

Results

All 25 eligible hospitals (51 ICUs) participated in serial point prevalence surveys over 8 survey periods (2008-2013). A total of 3909 adult ICU patients participated in the point prevalence surveys, with 432 (11.1%) found to be colonized with MRSA (95% confidence interval [CI], 10.1%-12.0%). The MRSA colonization prevalence among patients was unchanged during the study period; year-over-year relative risk for MRSA colonization was 0.97 (95% CI, .89-1.05; P = .48).

Conclusions

MRSA colonization prevalence among critically ill adult patients did not decline during the time period following legislatively mandated MRSA active surveillance. Our findings highlight the limits of legislated MRSA active surveillance as a strategy to reduce MRSA colonization burden among ICU patients.

Control of healthcare- and community-associated MRSA: recent progress and persisting challenges

BACKGROUND

Healthcare adapted meticillin-resistant Staphylococcus aureus (MRSA) has spread to hospitals around the world over 50 years. More recently, other strains of MRSA have emerged with the ability to spread in the community and infect otherwise healthy individuals. Morbidity and mortality associated with MRSA remains high and its control in both the healthcare and community setting has proven challenging.

SOURCES OF DATA

Pubmed (Medline).

AREAS OF AGREEMENT

The use of targeted screening and decolonization, hand hygiene and antimicrobial stewardship is supported by the most robust studies, though many studies have implemented bundles for effective healthcare-associated (HA)-MRSA control.

AREAS OF CONTENTION

Universal screening, universal decolonization and contact precautions for HA-MRSA control are supported by less evidence. Some interventions may not be cost-effective. Contact precautions may be associated with potential for patient harm. Evidence for effective control community acquired (CA)-MRSA is largely lacking.

GROWING POINTS

Programmes that focus on implementing bundles of interventions aimed at targeting HA-MRSA are more likely to be effective, with an emphasis on hand hygiene as a key component. Control of CA-MRSA is likely to be more difficult to achieve and relies on prevalence, risk factors and community healthcare interactions on a broader scale.

AREAS TIMELY FOR DEVELOPING RESEARCH

Further research in the area of CA-MRSA in particular is required. Antimicrobial stewardship for both CA and HA-MRSA is promising, as is the role of whole genome sequencing in characterizing transmission. However, further work is required to assess their long-term roles in controlling MRSA. With many institutions applying widespread use of chlorhexidine washes, monitoring for chlorhexidine resistance is paramount to sustaining efforts at controlling MRSA.

Adjunctive rifampicin for Staphylococcus aureus bacteraemia (ARREST): a multicentre, randomised, double-blind, placebo-controlled trial

BACKGROUND

Staphylococcus aureus bacteraemia is a common cause of severe community-acquired and hospital-acquired infection worldwide. We tested the hypothesis that adjunctive rifampicin would reduce bacteriologically confirmed treatment failure or disease recurrence, or death, by enhancing early S aureus killing, sterilising infected foci and blood faster, and reducing risks of dissemination and metastatic infection.

METHODS

In this multicentre, randomised, double-blind, placebo-controlled trial, adults (≥18 years) with S aureus bacteraemia who had received ≤96 h of active antibiotic therapy were recruited from 29 UK hospitals. Patients were randomly assigned (1:1) via a computer-generated sequential randomisation list to receive 2 weeks of adjunctive rifampicin (600 mg or 900 mg per day according to weight, oral or intravenous) versus identical placebo, together with standard antibiotic therapy. Randomisation was stratified by centre. Patients, investigators, and those caring for the patients were masked to group allocation. The primary outcome was time to bacteriologically confirmed treatment failure or disease recurrence, or death (all-cause), from randomisation to 12 weeks, adjudicated by an independent review committee masked to the treatment. Analysis was intention to treat. This trial was registered, number ISRCTN37666216, and is closed to new participants.

FINDINGS

Between Dec 10, 2012, and Oct 25, 2016, 758 eligible participants were randomly assigned: 370 to rifampicin and 388 to placebo. 485 (64%) participants had community-acquired S aureus infections, and 132 (17%) had nosocomial S aureus infections. 47 (6%) had meticillin-resistant infections. 301 (40%) participants had an initial deep infection focus. Standard antibiotics were given for 29 (IQR 18-45) days; 619 (82%) participants received flucloxacillin. By week 12, 62 (17%) of participants who received rifampicin versus 71 (18%) who received placebo experienced treatment failure or disease recurrence, or died (absolute risk difference -1·4%, 95% CI -7·0 to 4·3; hazard ratio 0·96, 0·68-1·35, p=0·81). From randomisation to 12 weeks, no evidence of differences in serious (p=0·17) or grade 3-4 (p=0·36) adverse events were observed; however, 63 (17%) participants in the rifampicin group versus 39 (10%) in the placebo group had antibiotic or trial drug-modifying adverse events (p=0·004), and 24 (6%) versus six (2%) had drug interactions (p=0·0005).

INTERPRETATION

Adjunctive rifampicin provided no overall benefit over standard antibiotic therapy in adults with S aureus bacteraemia.

FUNDING

UK National Institute for Health Research Health Technology Assessment.

Investigation of a Cluster of Sequence Type 22 Methicillin-Resistant Staphylococcus aureus Transmission in a Community Setting

BACKGROUND

Whole-genome sequencing (WGS) has typically been used to confirm or refute hospital/ward outbreaks of methicillin-resistant Staphylococcus aureus (MRSA) identified through routine practice. However, appropriately targeted WGS strategies that identify routinely "undetectable" transmission remain the ultimate aim.

METHODS

WGS of MRSA isolates sent to a regional microbiological laboratory was performed as part of a 12-month prospective observational study. Phylogenetic analyses identified a genetically related cluster of E-MRSA15 isolated from patients registered to the same general practice (GP) surgery. This led to an investigation to identify epidemiological links, find additional cases, and determine potential for ongoing transmission.

RESULTS

We identified 15 MRSA-positive individuals with 27 highly related MRSA isolates who were linked to the GP surgery, 2 of whom died with MRSA bacteremia. Of the 13 cases that were further investigated, 11 had attended a leg ulcer/podiatry clinic. Cases lacked epidemiological links to hospitals, suggesting that transmission occurred elsewhere. Environmental and staff screening at the GP surgery did not identify an ongoing source of infection.

CONCLUSIONS

Surveillance in the United Kingdom shows that the proportion of MRSA bacteremias apportioned to hospitals is decreasing, suggesting the need for greater focus on the detection of MRSA outbreaks and transmission in the community. This case study confirms that the typically nosocomial lineage (E-MRSA15) can transmit within community settings. Our study exemplifies the continued importance of WGS in detecting outbreaks, including those which may be missed by routine practice, and suggests that universal WGS of bacteremia isolates may help detect outbreaks in low-surveillance settings.

Prevention and Control of Methicillin-Resistant Staphylococcus aureus in Acute Care Settings

Methicillin-resistant Staphylococcus aureus (MRSA) is a leading cause of health care-associated infections worldwide. Controversies with regard to the effectiveness of various MRSA control strategies have contributed to varying approaches to the control of this pathogen in different settings. However, new evidence from large-scale studies has emerged, particularly with regards to MRSA screening and decolonization strategies, which will inform future control practices. The implementation as well as outcomes of control measures in the real world is not only influenced by scientific evidence but also depends on economic, administrative, governmental, and political influences.

Life After USA300: The Rise and Fall of a Superbug

The community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) epidemic in the United States is largely attributable to the meteoric rise of a single clone, referred to as USA300. This strain not only spread across the United States in just a few years to become the predominant cause of staphylococcal disease, but it also appears to have increased the overall number of skin and soft-tissue infections (SSTIs), increasing the overall disease burden. While USA300 still constitutes a major public health burden, its prevalence may be decreasing in some parts of the United States. Other than an epidemic in South America due to a closely related strain, USA300 also seems to have been largely unable to establish itself as an endemic infection in other geographic locations. While there have been several hypotheses put forward to explain the enormous success of USA300, the reasons for its failures and its potential fall remain obscure. Far from being unique to USA300, the rise and fall of specific clones of S. aureus in human populations seems to be a common process that has occurred multiple times and in multiple locations. This review charts the rise of USA300 and the evidence that suggests that it may be in decline, and it considers how best to understand the future spread, containment, and possible extinction of CA-MRSA.