Blanket use of intranasal mupirocin for outbreak control and long-term prophylaxis of endemic methicillin-resistant Staphylococcus aureus in an open ward

A systematic review of the effectiveness of cohorting to reduce transmission of healthcare-associated C. difficile and multidrug-resistant organisms

BACKGROUND

Cohorting of patients and staff is a control strategy often used to prevent the spread of infection in healthcare institutions. However, a comprehensive evaluation of cohorting as a prevention approach is lacking.

METHODS

We performed a systematic review of studies that used cohorting as part of an infection control strategy to reduce hospital-acquired infections. We included studies published between 1966 and November 30, 2019, on adult populations hospitalized in acute-care hospitals.

RESULTS

In total, 87 studies met inclusion criteria. Study types were quasi-experimental "before and after" (n = 35), retrospective (n = 49), and prospective (n = 3). Case-control analysis was performed in 7 studies. Cohorting was performed with other infection control strategies in the setting of methicillin-resistant Staphylococcus aureus (MRSA, n = 22), Clostridioides difficile infection (CDI, n = 6), vancomycin-resistant Enterococcus (VRE, n = 17), carbapenem-resistant Enterobacteriaceae infections (CRE, n = 22), A. baumannii (n = 15), and other gram-negative infections (n = 5). Cohorting was performed either simultaneously (56 of 87, 64.4%) or in phases (31 of 87, 35.6%) to help contain transmission. In 60 studies, both patients and staff were cohorted. Most studies (77 of 87, 88.5%) showed a decline in infection or colonization rates after a multifaceted approach that included cohorting as part of the intervention bundle. Hand hygiene compliance improved in approximately half of the studies (8 of 15) during the respective intervention.

CONCLUSION

Cohorting of staff, patients, or both is a frequently used and reasonable component of an enhanced infection control strategy. However, determining the effectiveness of cohorting as a strategy to reduce transmission of MDRO and C. difficile infections is difficult, particularly in endemic situations.

Comprehensive strategy including prophylactic mupirocin to reduce Staphylococcus aureus colonization and infection in high-risk neonates

OBJECTIVE

To examine the use of long-term prophylactic mupirocin as part of a comprehensive strategy in reducing Staphylococcus aureus colonization and infection in a neonatal intensive care unit (NICU).

STUDY DESIGN

Twice daily mupirocin was applied to all infants admitted to the NICU throughout hospitalization starting in 2004. S. aureus surveillance was implemented in 2008. The efficacy of these practices was evaluated with a retrospective review of infants admitted from 2004 to 2010 found to be colonized or infected with S. aureus.

RESULT

During the study period, 66 of 6283 NICU infants had a S. aureus infection with 67% methicillin resistance. There were three distinctive S. aureus outbreaks, the first being a methicillin-resistant strain July 2004. After implementation of daily mupirocin, the outbreak was eradicated and the rate of S. aureus infection significantly decreased (1.82 to 0.40/1000 patient-days-at-risk, P=0.0049). Mupirocin was discontinued March 2005 followed by a methicillin-sensitive S. aureus outbreak November 2005. In December 2005, mupirocin was reinstituted and has continued to present day, again significantly reducing S. aureus infections (1.42 to 0.33/1000 patient-days-at-risk, P<0.0001) with zero isolates resistant to mupirocin. In the pre-mupirocin period, S. aureus colonization was upwards of 60% now with rates typically <5%. S. aureus colonization strongly predicted later invasive infection (P<0.0001).

CONCLUSION

Although controversial, prophylactic mupirocin in all NICU infants has acted as a barrier to colonization and markedly decreased S. aureus infection rates over a 5-year period.

Infection control for a methicillin-resistant Staphylococcus aureus outbreak in an advanced emergency medical service center, as monitored by molecular analysis

A methicillin-resistant Staphylococcus aureus (MRSA) outbreak occurred in an advanced emergency medical service center between 2010 and 2011. Our objective was to evaluate the status of the MRSA outbreak, as monitored by molecular analysis. Twenty-eight MRSA strains were isolated from blood samples from 11 patients, from other specimens (pharynx, nasal cavity, etc.) from 12 patients, from two environmental samples, and from the skin, middle nasal meatus, and urine of one patient each from other wards. Pulsed-field gel electrophoresis (PFGE) was performed to evaluate horizontal transmission. Molecular typing by PFGE showed that the 28 MRSA strains presented 7 patterns in total, and that 11 of the MRSA strains had the same PGFE pattern. Unselective use of intranasal mupirocin ointment, MRSA monitoring for new inpatients, and prevention of direct or indirect contact infection were performed. However, the number of inpatients with MRSA did not quickly decrease, and additional molecular typing by PFGE showed that 10 of 19 MRSA strains found (5 of 6 from blood, 5 of 13 from other specimens) were the same as those found previously. Lectures and ward rounds were performed repeatedly, and staff participation in ward rounds was suggested. Finally, the number of inpatients with MRSA significantly decreased more than 6 months after the intervention. Although the MRSA outbreak was thought to have ended, follow-up molecular typing by PFGE showed that horizontal transmission persisted. Our data suggest that various combinations of infection control measures are essential when dealing with an MRSA outbreak, and monitoring by molecular analysis using PFGE is useful to identify the status of the outbreak.

Topical antibacterial agents

Decreased systemic toxicity, ease of application, and increased concentrations at the target site are some of the important advantages topical antibacterial agents offer. This article reviews the literature on selected indications for these agents and provides in-depth examination of specific agents for the prophylaxis and treatment of skin and wound infections.

A stepwise approach to control an outbreak and ongoing transmission of methicillin-resistant Staphylococcus aureus in a neonatal intensive care unit

BACKGROUND

Preventing methicillin-resistant Staphylococcus aureus (MRSA) transmission in health care facilities where MRSA is endemic is challenging yet critical.

OBJECTIVE

We sought to determine the effectiveness of 2 bundles of interventions for preventing MRSA transmission in a neonatal intensive care unit (NICU).

METHODS

This retrospective cohort study included infants admitted to our NICU between September 1, 2004, and March 31, 2009. Following a MRSA outbreak between September 2004 and September 2005, preventing ongoing MRSA transmission remained a challenge. In July 2006, bundle-I, including culture-based active surveillance, preemptive contact precaution for up to 72 hours for new admissions, and cohorting assignment of direct caregivers was introduced for eradicating MRSA transmission. Bundle-II began in April 2007 and included bundle-1 measures except that the real-time polymerase chain reaction test replaced culture for the detection of MRSA.

RESULTS

This study identified 218 infants who developed MRSA infection or colonization and 151 instances of MRSA transmission during the study period. After instituting bundle-II, the transmission rate declined from 2.9 to 2.1 per 1000 patient-days-at-risk (incidence rate ratio, 1.4; 95% confidence interval: 0.9-2.2), and hospital-acquired MRSA infections declined from 1.3 to 0.5 per 1000 patient-days-at-risk (incidence rate ratio, 2.5; 95% confidence interval: 1.1-5.8).

CONCLUSION

Despite an increasing incidence of MRSA in community settings, preventing MRSA transmission within a NICU is achievable through implementation of optimal intervention strategies.

Topical antibacterial agents

Decreased systemic toxicity, ease of application, and increased concentrations at the target site are some of the important advantages topical antibacterial agents offer. This article reviews the literature on selected indications for these agents and provides in-depth examination of specific agents for the prophylaxis and treatment of skin and wound infections.

A simple prophylaxis regimen for MRSA: its impact on the incidence of infection in patients undergoing liver resection

INTRODUCTION

Methicillin-resistant Staphylococcus aureus (MRSA) infection has increased at an alarming rate in the recent past and has major cost implications. The aim of this study is to assess the impact of a policy of pre-operative MRSA prophylaxis on the incidence of MRSA infection in patients undergoing liver resection.

PATIENTS AND METHODS

A total of 585 patients underwent hepatectomy in a tertiary referral centre between January 2000 and September 2005. In September 2003, a policy of MRSA prophylaxis (nasal mupirocin and triclosan wash for 5 days) was introduced within this unit. Demographic, pathological and outcome data were compared between the pre- and post-MRSA prophylaxis cohorts.

RESULTS

The prevalence of MRSA infection prior to initiating the prophylaxis protocol was 29 patients (8.3%) and this fell to 9 patients (3.8%; P = 0.029). Furthermore, patients who had MRSA-related infection had a higher incidence of additional complications compared to the rest of the cohort (P = 0.001). Total cost savings incurred as a result of this protocol over the past 2 years has been approximated at 28,893 pounds.

CONCLUSIONS

Introduction of a simple MRSA prophylaxis policy has had a significant reduction on the incidence MRSA-related infection within our patient population, leading to reduced morbidity and cost saving to the UK National Health Service.

Health-care workers: source, vector, or victim of MRSA?

There is ongoing controversy about the role of health-care workers in transmission of meticillin-resistant Staphylococcus aureus (MRSA). We did a search of the literature from January, 1980, to March, 2006, to determine the likelihood of MRSA colonisation and infection in health-care workers and to assess their role in MRSA transmission. In 127 investigations, the average MRSA carriage rate among 33 318 screened health-care workers was 4.6%; 5.1% had clinical infections. Risk factors included chronic skin diseases, poor hygiene practices, and having worked in countries with endemic MRSA. Both transiently and persistently colonised health-care workers were responsible for several MRSA clusters. Transmission from personnel to patients was likely in 63 (93%) of 68 studies that undertook genotyping. MRSA eradication was achieved in 449 (88%) of 510 health-care workers. Subclinical infections and colonisation of extranasal sites were associated with persistent carriage. We discuss advantages and disadvantages of screening and eradication policies for MRSA control and give recommendations for the management of colonised health-care workers in different settings.

Risk Factors for Methicillin-Resistant Staphylococcus aureus (MRSA) and Use of a Nasal Mupirocin Ointment in Oral Cancer Inpatients

PURPOSE

Elimination of methicillin-resistant Staphylococcus aureus (MRSA) is of critical importance in oral and maxillofacial surgery because control is very difficult once infection of an oral tumor or oral wound with MRSA is established.

PATIENTS AND METHODS

We retrospectively investigated the risk factors for acquiring MRSA in 518 patients with oral cancer among 1,877 inpatients in our department between 1984 and 2005.

RESULTS

The patients with oral cancer demonstrated a high rate of MRSA colonization and infection (77.8%) relative to the population as a whole with MRSA isolated percentage in our department after 1991. The risk factors for MRSA in oral cancer patients are also related to systemic diseases and physiological and iatrogenic conditions, including cerebrovascular diseases (77.8%), peripheral arterial catheterization (69.2%), diabetes (50.0%), tracheotomy (50.0%), renal failure (50.0%), long-term broad-spectrum antibiotic use (45.7%), and malnutrition (43.3%). However, the highest risk of MRSA seems to be related to poor hygienic care.

CONCLUSIONS

Beginning in 1999, we implemented a strategy for reducing infection by MRSA that included nasal mupirocin ointment for patients at high risk of MRSA; since then, the detection rate has decreased. We suggest that the administration of nasal mupirocin ointment and provision of scrupulous hygienic care for high-risk patients are useful and effective measures for decreasing the incidence of MRSA infection.

Impact of prophylactic mupirocin for radical esophagectomy

The preoperative intranasal application of mupirocin significantly decreases the rate of nosocomial S. aureus infections among patients who are S. aureus carriers. However, it remains unclear whether the routine preoperative use of mupirocin would reduce postoperative S. aureus infections, especially methicillin-resistant Staphylococcus aureus (MRSA) infections, and who would benefit from the prophylactic use of mupirocin. Ninety-six consecutive patients who had undergone elective radical esophagectomy with right thoracotomy and laparotomy were evaluated. Fifty-one patients were given 2% mupirocin calcium ointment 3 times daily over 3 consecutive days before surgery. Uni- and multivariate analyses were performed to identify factors affecting the following three issues: postoperative MRSA infection, postoperative pneumonia, and the length of postoperative hospital stay. In univariate analyses, the preoperative application of mupirocin significantly reduced MRSA infection, postoperative pneumonia, and length of postoperative hospital stay. Multivariate analyses indicated significant associations between mupirocin administration and reductions in both MRSA infection and postoperative pneumonia, but not in length of postoperative hospital stay. Radical esophagectomy with right thoracotomy and laparotomy for esophageal carcinoma warranted the preoperative prophylactic administration of mupirocin in order to reduce postoperative infectious complications from MRSA. Its routine use for such a high-risk procedure is entirely reasonable.

Control of a methicillin-resistant Staphylococcus aureus (MRSA) outbreak in a day-care institution

This article describes an outbreak of methicillin-resistant Staphylococcus aureus (MRSA) in two institutions for multi-handicapped children in Copenhagen. The aim of the study was to determine whether it was possible to eradicate MRSA in a setting with multi-handicapped children and staff where there was a high degree of physical interaction. This was a prospective interventional uncontrolled cohort study that took place from January 2003 to March 2005. All individuals in close contact with the two institutions and/or in close contact with an MRSA-colonized subject from the outbreak were included in the study: 38 children, 60 staff members and 12 close relatives of colonized subjects. Infection control measures included screening all individuals. When MRSA infection or colonization was found, an attempt was made to eradicate MRSA, staff education was undertaken and attempts were made to determine the route of transmission. Eleven individuals were found to be positive for MRSA (10.0%). All isolates were identical by pulsed-field gel electrophoresis and harboured the staphylococcal cassette chromosome mec (SCCmec) type IV. All colonized and infected individuals were associated with a single room in one of the institutions. MRSA was eradicated from all the colonized and infected subjects. This study shows that it is possible to control an MRSA outbreak in institutions for multi-handicapped children where there is a high degree of physical contact.

A systematic review of the evidence for interventions for the prevention and control of meticillin-resistant Staphylococcus aureus (1996–2004): report to the Joint MRSA Working Party (Subgroup A)

A systematic review was undertaken of the evidence published between 1996 and 2004 on the effectiveness, and associated economic costs, of a range of interventions to prevent and control the transmission of meticillin-resistant Staphylococcus aureus (MRSA) in hospital settings. The review questions focused on screening, patient isolation, use of decolonization strategies, feedback of surveillance data, and environmental hygiene interventions. The reviewers assessed evidence from four recent systematic reviews, 24 non-experimental descriptive studies, five economic evaluations and one recently revised international guideline. The methodological quality of studies retrieved was such that there is currently insufficient high-quality evidence for infection prevention and control interventions in the fields identified for this review. However, evidence from clinically based, non-experimental studies does provide support for the continued use of a range and combination of interventions that contribute to the prevention and control of MRSA within acute hospitals and long-term-care settings. Well-conducted economic evaluations reporting the economic benefits arising from infection prevention and control interventions are lacking.

Guidelines for the prophylaxis and treatment of methicillin-resistant Staphylococcus aureus (MRSA) infections in the UK

These evidence-based guidelines have been produced after a literature review of the treatment and prophylaxis of methicillin-resistant Staphylococcus aureus (MRSA) infection. The guidelines were further informed by antibiotic susceptibility data on MRSA from the UK. Recommendations are given for the treatment of common infections caused by MRSA, elimination of MRSA from carriage sites and prophylaxis of surgical site infection. There are several antibiotics currently available that are suitable for use in the management of this problem and potentially useful new agents are continuing to emerge.

Isolation measures in the hospital management of methicillin resistant Staphylococcus aureus (MRSA): systematic review of the literature

OBJECTIVE

To evaluate the evidence for the effectiveness of isolation measures in reducing the incidence of methicillin resistant Staphylococcus aureus (MRSA) colonisation and infection in hospital inpatients.

DESIGN

Systematic review of published articles.

DATA SOURCES

Medline, Embase, CINAHL, Cochrane Library, System for Information on Grey Literature in Europe (SIGLE), and citation lists (1966-2000).

REVIEW METHODS

Articles reporting MRSA related outcomes and describing an isolation policy were selected. No quality restrictions were imposed on studies using isolation wards or nurse cohorting. Other studies were included if they were prospective or employed planned comparisons of retrospective data.

RESULTS

46 studies were accepted; 18 used isolation wards, nine used nurse cohorting, and 19 used other isolation policies. Most were interrupted time series, with few planned formal prospective studies. All but one reported multiple interventions. Consideration of potential confounders, measures to prevent bias, and appropriate statistical analysis were mostly lacking. No conclusions could be drawn in a third of studies. Most others provided evidence consistent with a reduction of MRSA acquisition. Six long interrupted time series provided the strongest evidence. Four of these provided evidence that intensive control measures including patient isolation were effective in controlling MRSA. In two others, isolation wards failed to prevent endemic MRSA.

CONCLUSION

Major methodological weaknesses and inadequate reporting in published research mean that many plausible alternative explanations for reductions in MRSA acquisition associated with interventions cannot be excluded. No well designed studies exist that allow the role of isolation measures alone to be assessed. None the less, there is evidence that concerted efforts that include isolation can reduce MRSA even in endemic settings. Current isolation measures recommended in national guidelines should continue to be applied until further research establishes otherwise.

Topical antibacterial agents

Decreased systemic toxicity, ease of application, and increased concentration at the target site are some of the important advantages topical antibacterial agents offer. This article reviews the literature on selected indications of these agents and provides in-depth examination of specific agents for the prophylaxis and treatment of skin and wound infections.

Control of endemic MRSA-what is the evidence? A personal view

Although there is extensive literature on the control of MRSA, when that concerning epidemics is excluded, only a limited amount remains regarding the control of endemic MRSA. Several guidelines have been recently published recommending stringent control measures, which are often suggested based on their success in controlling MRSA outbreaks in hospitals with few MRSA or in containing MRSA cases introduced into a hospital with no MRSA. In these settings, multiple measures are usually introduced with apparently successful results. However, results may not be generalizable to other settings and we do not know the minimum effective measures required for MRSA containment. This paper aims critically to review the literature to determine whether evidence exists for the value of the infection control measures that are widely recommended in the endemic setting. Much of this literature is based on observational studies, with few randomized, controlled trials having been conducted. More well-designed studies are required before many of the principles on which we build infection control programmes can be regarded as evidence based.

Inhibition of methicillin-resistant Staphylococcus aureus colonization of oral cavities in newborns by viridans group streptococci

We investigated the role of viridans group streptococci in the prevention of colonization with methicillin-resistant Staphylococcus aureus (MRSA) in neonatal intensive care units. During a 26-month period at a children's hospital, 207 (49.9%) of 415 newborns were colonized with MRSA by the time of discharge. Two groups of newborns with matching durations of hospitalization were compared with regard to the prevalence of future colonization with MRSA: group 1 (103 patients) did not acquire colonization with viridans group streptococci and group 2 (63 patients) did acquire colonization with viridans group streptococci at birth or by 1 to 2 weeks (age, < or =11 days). The rate of colonization among patients in group 2 (9.5%) was significantly lower than that among patients in group 1 (44.7%; P<.001). No significant difference in patient characteristics (e.g., birth weight, diseases) was observed. These results indicate that viridans group streptococci, as bacteria that formerly occupied the oral cavities in newborns, may inhibit later colonization with MRSA.

Control of a methicillin-resistant Staphylococcus aureus outbreak in a neonatal intensive care unit by unselective use of nasal mupirocin ointment

In September 1996, an outbreak of methicillin-resistant Staphylococcus aureus (MRSA) colonization occurred in the neonatal intensive care unit (NICU) of our hospital. After failing to control the outbreak by conventional methods we implemented an intranasal blanket use programme of mupirocin ointment from the beginning of November 1997. In the programme, patients who had been carrying MRSA received intranasal administration of the ointment three times daily for the first three days and consecutively three times weekly, while newly admitted patients and those who had not been colonized were prophylactically medicated three times weekly. This blanket administration was executed for one month. Methicillin-resistant Staphylococcus aureus colonization became undetectable in all but one intubated inpatient who had already been colonized before the start of the programme, and no new acquisitions occurred until the middle of January 1998, seven weeks after the termination of the blanket use programme. The rate of colonized patients in the unit also decreased. During and after the programme, neither an increase in minimum inhibitory concentration for the antibiotic nor apparent adverse reactions in any of the treated patients were observed. We concluded that this procedure is an effective method of controlling an MRSA outbreak in an NICU when the outbreak cannot be managed with conventional measures.

Topical antibacterial agents

Topical antibacterial agents occupy an important niche of antimicrobial therapy for both inpatients and outpatients. These agents, including antiseptic and antibiotic preparations, are used for prophylaxis and treatment of infection. Prophylactic uses include application for traumatic and surgical wounds, burns, intravascular catheters, and eradication of S. aureus nasal carriage. Topical antibacterial agents are also used for treatment of primary and secondary pyodermas. Individual antibacterial agents have been reviewed. Of note, despite the widespread use of topical antibacterial agents, further data on which to guide therapy are needed in many instances.

Bacterial interference among nasal inhabitants: eradication of Staphylococcus aureus from nasal cavities by artificial implantation of Corynebacterium sp

To evaluate the role of normal flora in the nares in preventing Staphylococcus aureus colonization, we conducted a replacement study in vivo. Staphylococcus epidermidis (rate of colonization: 100%), various species of corynebacteria (52.5%) and S. aureus (25.%) were the major bacterial inhabitants in the nares of 156 healthy volunteers. The low incidence of S. aureus colonization in the carriers with corynebacteria (8.5%), compared to non-carriers (44. 5%) indicated the possibility of competition for survival between S. aureus and corynebacteria. To confirm this hypothesis, we artificially implanted a strain of Corynebacterium sp (API Coryne bioprofile; 5100304), denoted as Co304 into the nares of 17 S. aureus carriers. S. aureus was completely eradicated in 71% of carriers by up to 15 inoculations of Co304. However, similar doses of 0.9% NaCl or S. epidermidis into the nares of 10 volunteers did not eradicate S. aureus. No bacteriocin-like activity against S. aureus was detectable, even after mitomycin C stimulation of Co304. Thus Co304 interfered with S. aureus by a different mechanism to a bacteriocin-like activity.

Randomized, placebo-controlled, double-blind trial to evaluate the efficacy of mupirocin for eradicating carriage of methicillin-resistant Staphylococcus aureus

Mupirocin has been widely used for the clearance of nasal methicillin-resistant Staphylococcus aureus (MRSA) carriage during outbreaks, but no placebo-controlled trial has evaluated its value for eradicating MRSA carriage at multiple body sites in settings where MRSA is not epidemic. In a 1,500-bed teaching hospital with endemic MRSA, 102 patients colonized with MRSA were randomized into a double-blind, placebo-controlled trial and treated with either mupirocin (group M) or placebo (group P) applied to the anterior nares for 5 days; both groups used chlorhexidine soap for body washing. Follow-up screening, susceptibility testing, and genotyping were performed to evaluate treatment success, mupirocin or chlorhexidine resistance, and exogenous recolonization. At baseline, MRSA carriage was 60% in the nares, 38% in the groin, and 62% in other sites (skin lesions, urine). The MRSA eradication rate (all body sites) was 25% in group M (12 of 48 patients), compared to 18% in group P (9 of 50 patients; relative risk [RR], 0.72; 95% confidence interval [CI95], 0.33 to 1.55). At the end of follow-up, 44% of patients (19 of 43) were free of nasal MRSA in group M, compared to 23% (11 of 44) in group P (RR, 0.57; CI95, 0.31 to 1.04). Ten patients developed MRSA infections (three in group M and seven in group P). One mupirocin treatment failure was due to exogenous MRSA recolonization. No MRSA isolate showed chlorhexidine resistance or high-level mupirocin resistance; however, we observed an association (P = 0.003) between low-level mupirocin resistance at study entry (prevalence, 23%) and subsequent treatment failure in both study arms. These results suggest that nasal mupirocin is only marginally effective in the eradication of multisite MRSA carriage in a setting where MRSA is endemic.

The evaluation of a cadexomer iodine wound dressing on methicillin resistant Staphylococcus aureus (MRSA) in acute wounds

BACKGROUND

Many bacteria have become resistant to commonly-used antibiotics.

OBJECTIVE

The purpose of this study was to examine the effect of a cadexomer iodine wound dressing on methicillin resistant Staphylococcus aureus (MRSA).

METHOD

Partial thickness wounds were made on the backs of three pigs and inoculated with a known amount of MRSA. Wounds were treated with either cadexomer iodine dressing or vehicle dressing (without iodine), or they were left untreated. Three wounds from each treatment group per animal were cultured using quantitative scrub techniques after 24, 48, or 72 hours of treatment.

CONCLUSIONS

The cadexomer iodine dressing significantly reduced MRSA and total bacteria in the wounds as compared to both the no treatment control and vehicle. No significant differences were observed in the number of bacteria recovered between the no treatment control and cadexomer (vehicle) treated wounds. Cadexomer iodine may be an effective agent for preventing proliferation of MRSA in wounds.