Meticillin-resistant Staphylococcus aureus (MRSA) acquisition risk in an endemic neonatal intensive care unit with an active surveillance culture and decolonization programme

Impact of active surveillance and decolonization strategies for methicillin-resistant Staphylococcus aureus in a neonatal intensive care unit

OBJECTIVE

To assess the impact of active surveillance and decolonization strategies on methicillin-resistant Staphylococcus aureus (MRSA) infection rates in a NICU.

STUDY DESIGN

MRSA infection rates were compared before (2014-2016) and during (2017-2022) an active surveillance program. Eligible infants were decolonized with chlorohexidine gluconate (CHG) bathing and/or topical mupirocin. Successful decolonization and rates of recolonization were assessed.

RESULTS

Fifty-two (0.57%) of 9 100 hospitalized infants had invasive MRSA infections from 2014 to 2022; infection rates declined non-significantly. During the 6-year surveillance program, the risk of infection was 16.9-times [CI95 8.4, 34.1] higher in colonized infants than uncolonized infants. Those colonized with mupirocin-susceptible MRSA were more likely successfully decolonized (aOR 9.7 [CI95 4.2, 22.5]). Of 57 infants successfully decolonized who remained hospitalized, 34 (60%) became recolonized.

CONCLUSIONS

MRSA infection rates did not significantly decline in association with an active surveillance and decolonization program. Alternatives to mupirocin and CHG are needed to facilitate decolonization.

SHEA/IDSA/APIC Practice Recommendation: Strategies to prevent methicillin-resistant Staphylococcus aureus transmission and infection in acute-care hospitals: 2022 Update

Previously published guidelines have provided comprehensive recommendations for detecting and preventing healthcare-associated infections (HAIs). The intent of this document is to highlight practical recommendations in a concise format designed to assist acute-care hospitals in implementing and prioritizing efforts to prevent methicillin-resistant Staphylococcus aureus (MRSA) transmission and infection. This document updates the "Strategies to Prevent Methicillin-Resistant Staphylococcus aureus Transmission and Infection in Acute Care Hospitals" published in 2014.1 This expert guidance document is sponsored by the Society for Healthcare Epidemiology of America (SHEA). It is the product of a collaborative effort led by SHEA, the Infectious Diseases Society of America (IDSA), the Association for Professionals in Infection Control and Epidemiology (APIC), the American Hospital Association (AHA), and The Joint Commission, with major contributions from representatives of a number of organizations and societies with content expertise.

Transmission routes of antibiotic resistant bacteria: a systematic review

Background

Quantification of acquisition routes of antibiotic resistant bacteria (ARB) is pivotal for understanding transmission dynamics and designing cost-effective interventions. Different methods have been used to quantify the importance of transmission routes, such as relative risks, odds ratios (OR), genomic comparisons and basic reproduction numbers. We systematically reviewed reported estimates on acquisition routes’ contributions of ARB in humans, animals, water and the environment and assessed the methods used to quantify the importance of transmission routes.

Methods

PubMed and EMBASE were searched, resulting in 6054 articles published up until January 1st, 2019. Full text screening was performed on 525 articles and 277 are included.

Results

We extracted 718 estimates with S. aureus (n = 273), E. coli (n = 157) and Enterobacteriaceae (n = 99) being studied most frequently. Most estimates were derived from statistical methods (n = 560), mainly expressed as risks (n = 246) and ORs (n = 239), followed by genetic comparisons (n = 85), modelling (n = 62) and dosage of ARB ingested (n = 17). Transmission routes analysed most frequently were occupational exposure (n = 157), travelling (n = 110) and contacts with carriers (n = 83). Studies were mostly performed in the United States (n = 142), the Netherlands (n = 87) and Germany (n = 60). Comparison of methods was not possible as studies using different methods to estimate the same route were lacking. Due to study heterogeneity not all estimates by the same method could be pooled.

Conclusion

Despite an abundance of published data the relative importance of transmission routes of ARB has not been accurately quantified. Links between exposure and acquisition are often present, but the frequency of exposure is missing, which disables estimation of transmission routes’ importance. To create effective policies reducing ARB, estimates of transmission should be weighed by the frequency of exposure occurrence.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-022-07360-z.

Management and Prevention of Staphylococcus aureus Infections in Children

Staphylococcus aureus is a common skin commensal with the potential to cause severe infections resulting in significant morbidity and mortality. Up to 30% of individuals are colonized with S aureus, though infection typically does not occur without skin barrier disruption. Infection management includes promptly addressing the source of infection, including sites of metastatic infection, and initiation of effective antibiotics, which should be selected based on local antibiotic susceptibility patterns. Given that S aureus colonization is a risk factor for infection, preventive strategies are aimed at optimizing hygiene measures and decolonization regimens for outpatients and critically ill children with prolonged hospitalizations.

Risk factors for nosocomial methicillin resistant Staphylococcus aureus (MRSA) colonization in a neonatal intensive care unit: A Case-control study

AIM

To determine risk factors for MRSA colonization in a Level IV Neonatal Intensive Care Unit (NICU) independent of length of stay and gestational age in the context of a persistently circulating MRSA clone.

DESIGN

Retrospective matched case-control study.

SETTING

Level IV NICU PATIENTS: Infants admitted between April 4,2017- March 31,2018.

METHODS

Based on weekly surveillance cultures, infants who acquired MRSA were matched 1:1 with MRSA-negative control infants by duration of exposure (length of stay) and gestational age to determine risk factors for acquisition.

RESULTS

Fifty case infants were matched with controls. Isolates from 45 of the 50 cases were mupirocin-resistant and related by pulse-field gel electrophoresis. On matched univariable analysis, the following were significantly associated with a risk for MRSA acquisition: 1.Bed location in the acute area(P = 0.03), 2.Requirement of any level of respiratory support during the week prior to MRSA detection(P = 0.04), 3.Higher ATP pass rate (a measure of effectiveness of cleaning) during the week of and week prior(P = 0.01), 4.Higher MRSA colonization pressure during the week of and week prior(P< 0.0001), 5.Not having a hearing test during the time between the previous negative culture and MRSA acquisition(P = 0.01). A multivariable conditional logistic regression model (that excluded ATP pass rate) found that only colonization pressure was associated with acquisition of MRSA colonization.

CONCLUSIONS

In an outbreak setting, MRSA colonization pressure is significantly associated with MRSA acquisition in the NICU independent of length of stay and gestational age.

Prevalence of MRSA nasal carriage among pregnant women in Copenhagen

Background

Methicillin resistant Staphylococcus aureus (MRSA) frequently causes outbreaks in neonatal intensive care units (NICUs). It is believed that MRSA predominantly enters the NICU with MRSA colonized parents. In Denmark, 27 MRSA NICU outbreaks have been registered between 2008 and 2019.

Aim

The aim of this study was to determine the prevalence of MRSA nasal carriage in pregnant women in Copenhagen and to clarify if MRSA screening during pregnancy could add to the prevention of NICU outbreaks.

Methods

All pregnant women 18 years or older were offered MRSA nasal screening at their first midwife visit between 13 and 20 weeks of gestation.

Results

1778 pregnant women were included, two (0.11%) carried MRSA in the nose.

Conclusion

Infants of the two MRSA positive women were not admitted to a NICU and therefore the screening had no impact on NICU outbreaks. The low prevalence of MRSA found in this study does not justify MRSA screening of all pregnant women in Denmark.

Role of surveillance cultures in infection control

Hospital-acquired infections are a known menace to the primary disease, for which a patient is admitted. These infections are twenty times more common in developing countries than in the developed ones. Surveillance for colonised patients can be passive or active process. In many hospitals, active surveillance culture for certain sentinel organisms followed by contact precautions for the same is an important part of infection control policy. Specific measures can be taken on early detection of multidrug-resistant organism, allowing prevention of widespread transmission in hospitals. Cultures are the most conventional and economical microbiological method of detection. The cost of active surveillance is a major challenge, especially for developing nations. These nations lack basic infrastructure and have logistic issues. The guidelines regarding this are not very clearly delineated for developing countries. Each hospital has its own challenges and the process is to be tailor-made accordingly. The following review delineates the various aspects of active surveillance for the colonisation of various organisms and the advantages and disadvantages of the same.

One Health in hospitals: how understanding the dynamics of people, animals, and the hospital built-environment can be used to better inform interventions for antimicrobial-resistant gram-positive infections

Despite improvements in hospital infection prevention and control, healthcare associated infections (HAIs) remain a challenge with significant patient morbidity, mortality, and cost for the healthcare system. In this review, we use a One Health framework (human, animal, and environmental health) to explain the epidemiology, demonstrate key knowledge gaps in infection prevention policy, and explore improvements to control Gram-positive pathogens in the healthcare environment. We discuss patient and healthcare worker interactions with the hospital environment that can lead to transmission of the most common Gram-positive hospital pathogens – methicillin-resistant Staphylococcus aureus, Clostridioides (Clostridium) difficile, and vancomycin-resistant Enterococcus – and detail interventions that target these two One Health domains. We discuss the role of animals in the healthcare settings, knowledge gaps regarding their role in pathogen transmission, and the absence of infection risk mitigation strategies targeting animals. We advocate for novel infection prevention and control programs, founded on the pillars of One Health, to reduce Gram-positive hospital-associated pathogen transmission.

A survey of the implementation status of selected infection control strategies in neonatal intensive care units in Japan

BACKGROUND

Infection control strategies are implemented in all neonatal intensive care units (NICUs); however, the details of the strategies seem to differ among institutions. The purpose of this survey was to investigate the current implementation status of infection control strategies in NICUs in Japan and to identify and recommend appropriate strategies for the prevention of outbreaks in neonatal units.

METHODS

This survey documented the current implementation status and methods of selected infection prevention and control measures (active surveillance cultures and standard precaution) in 453 Japanese NICUs/neonatal units registered with the Japan Society of Perinatal and Neonatal Medicine, using questionnaires, in May 2018.

FINDINGS

The response rate was 48.1% (level I institutions, 25.5%; level II, 55.9%; level III, 64.2%). Surveillance cultures were performed every week and targeted all bacteria in most units. The proportion of level III institutions that experienced outbreaks over the previous five years was significantly higher than that of level II institutions (55% vs 27%, P=0.0003). However, wearing a mask was less frequently recommended in level III institutions (55.7%) than in level II institutions (67.9%). Meticillin-resistant Staphylococcus aureus (MRSA) was the most frequently reported bacterial pathogen responsible for NICU outbreaks.

CONCLUSION

Infection prevention and control practices regarding active pathogen surveillance cultures and the use of barrier precautions varied widely in Japanese neonatal units. National guidelines and evidence-based recommendations are needed to rationalize and standardize current infection prevention and control practices in neonatal units in Japan.

Impact of MRSA Transmission and Infection in a Neonatal Intensive Care Unit in China: A Bundle Intervention Study during 2014-2017

Objective. To evaluate the efficacy of bundle intervention on healthcare-associated (HA) methicillin-resistant Staphylococcus Aureus (MRSA) infection in the neonatal intensive care unit (NICU). Methods. In this study, 11,277 infants having undergone treatment at the NICU in Xiamen, China, from January 2014 to February 2017 were recruited. We retrospectively reviewed patients' demographic and clinical information. Patients from 2014 to 2015 were treated as the control group and those from 2016 to 2017 were classified as the experimental group. Bundle intervention measures were performed, including screening for MRSA, isolation precautions, training of hand hygiene, cleaning protocols, and decontamination of isolation ward. The HA-MRSA data and compliance of infection control measures between both groups were analyzed. Results. Through bundle interventions, the compliance with the isolation of MRSA raised from 55.88% to 92.86% and hand hygiene compliance increased from 90.07% to 93.23% (P < 0.05). The HA infection decreased from 1.87% to 1.71% (P > 0.05) and HA detection rate of MRSA declined from 2.63‰ to 1.00‰, respectively (P < 0.05). Conclusion. Multifaceted interventions can effectively prevent MRSA infection and transmission; this includes active surveillance, isolation precautions, increased hand hygiene compliance, environmental cleaning, and decontamination.

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

BACKGROUND

The value of decolonization as a strategy for preventing methicillin-resistantStaphylococcus aureus (MRSA) in the neonatal intensive care unit (NICU) remains to be determined.

OBJECTIVE

After adding decolonization to further reduce MRSA transmission in our NICU, we conducted this retrospective review to evaluate its effectiveness.

METHOD

The review included patients who were admitted to our NICU between April 2015 and June 2018 and were eligible for decolonization including twice daily intranasal mupirocin and daily chlorhexidine gluconate bathing over 5 consecutive days. Patients were considered successfully decolonized if 3 subsequent MRSA screenings conducted at 1-week intervals were negative. The MRSA acquisition rate (AR) was calculated as hospital-acquired (HA) MRSA per 1,000 patient days (PD) and was used to measure the effectiveness of the decolonization.

RESULTS

Of the 151 MRSA patients being reviewed, 78 (51.6%) were HA-MRSA, resulting in an overall AR of 1.27 per 1,000 PD. Between April 2015 and February 2016, when only the decolonization was added, the AR was 2.38 per 1,000 PD. Between March 2016 and June 2018 after unit added a technician dedicated to the cleaning of reusable equipment, the AR decreased significantly to 0.92 per 1,000 PD (P < .05). Of the 78 patients who were started on the decolonization, 49 (62.8%) completed the protocol, 11 (14.1%) remained colonized, and 13 (16.7%) were recolonized prior to NICU discharge.

CONCLUSION

In a NICU with comprehensive MRSA prevention measures in place, enhancing the cleaning of reusable equipment, not decolonization, led to significant reduction of MRSA transmission.

A cost analysis of active surveillance culture in a neonatal intensive care unit

Active surveillance culture (ASC) in neonatal intensive care units (NICUs) has been implemented to monitor horizontal transmission and choose appropriate antimicrobials when neonates experience late-onset infections (LOIs). To perform a cost analysis of ASC in the NICU, we evaluated data from a NICU ward in a Japanese community hospital. This was a retrospective study of neonates admitted to the NICU of Nara Prefecture General Medical Center, Nara City, Japan, from April 2012 to May 2017. We implemented biweekly ASC (nasal, stool and umbilical cultures) during this period. We assessed the detection rate for methicillin-sensitive and -resistant S. aureus (MSSA and MRSA) in each culture and reviewed the cases of LOI. Among the 785 cases, MSSA and MRSA were detected in 158 and 75 cases, respectively. Nasal culture was the most sensitive method for detecting MSSA and MRSA. Three cases benefitted from changing the empiric treatment based on previous ASC results, with an annual cost of ¥808,331 (£5773.80 or $7282.30) for ASC. The total cost per one benefited case during the study period was calculated as ¥1,392,126 (£9943.80 or $12,541.70). The total cost per benefited case in risk factor targeted ASC, nasal culture targeted ASC and MRSA-targeted ASC was ¥1,332,264 (£9516.20 or $12,002.30), ¥692,222 (£4944.40 or $6236.20) and ¥858,547 (£6132.50 or $7734.70), respectively. Considering the frequency of S. aureus detection and the cost of each culture, our ASC was modified to use only nasal cultures. This study suggests that the cost performance of ASC should be evaluated with consideration of the characteristics of each NICU.

Whole-genome sequencing data-based modeling for the investigation of an outbreak of community-associated methicillin-resistant Staphylococcus aureus in a neonatal intensive care unit in Hong Kong

We describe a nosocomial outbreak of community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) ST59-SCCmec type V in a neonatal intensive care unit (NICU) in Hong Kong. In-depth epidemiological analysis was performed by whole-genome sequencing (WGS) of the CA-MRSA isolates collected from patients and environment during weekly surveillance and healthcare workers from the later phase of the outbreak. Case-control analysis was performed to analyze potential risk factors for the outbreak. The outbreak occurred from September 2017 to February 2018 involving 15 neonates and one healthcare worker. WGS analysis revealed complicated transmission dynamics between patients, healthcare worker, and environment, from an unrecognized source introduced into the NICU within 6 months before the outbreak. In addition to enforcement of directly observed hand hygiene, environmental disinfection, cohort nursing of colonized and infected patients, together with contact tracing for secondary patients, medical, nursing, and supporting staff were segregated where one team would care for CA-MRSA-confirmed/CA-MRSA-exposed patients and the other for newly admitted patients in the NICU only. Case-control analysis revealed use of cephalosporins [odds ratio 49.84 (3.10-801.46), p = 0.006] and length of hospitalization [odds ratio 1.02 (1.00-1.04), p = 0.013] as significant risk factors for nosocomial acquisition of CA-MRSA in NICU using multivariate analysis. WGS facilitates the understanding of transmission dynamics of an outbreak, providing insights for outbreak prevention.

Mupirocin for Staphylococcus aureus Decolonization of Infants in Neonatal Intensive Care Units

: media-1vid110.1542/5849573989001PEDS-VA_2018-1565Video Abstract BACKGROUND AND OBJECTIVES: Staphylococcus aureus (SA) is the second leading cause of late-onset sepsis among infants in the NICU. Because colonization of nasal mucosa and/or skin frequently precedes invasive infection, decolonization strategies, such as mupirocin application, have been attempted to prevent clinical infection, but data supporting this approach in infants are limited. We conducted a phase 2 multicenter, open-label, randomized trial to assess the safety and efficacy of intranasal plus topical mupirocin in eradicating SA colonization in critically ill infants.

METHODS

Between April 2014 and May 2016, infants <24 months old in the NICU at 8 study centers underwent serial screening for nasal SA. Colonized infants who met eligibility criteria were randomly assigned to receive 5 days of mupirocin versus no mupirocin to the intranasal, periumbilical, and perianal areas. Mupirocin effects on primary (day 8) and persistent (day 22) decolonization at all three body sites were assessed.

RESULTS

A total of 155 infants were randomly assigned. Mupirocin was generally well tolerated, but rashes (usually mild and perianal) occurred significantly more often in treated versus untreated infants. Primary decolonization occurred in 62 of 66 (93.9%) treated infants and 3 of 64 (4.7%) control infants (P < .001). Twenty-one of 46 (45.7%) treated infants were persistently decolonized compared with 1 of 48 (2.1%) controls (P < .001).

CONCLUSIONS

Application of mupirocin to multiple body sites was safe and efficacious in eradicating SA carriage among infants in the NICU; however, after 2 to 3 weeks, many infants who remained hospitalized became recolonized.

Healthcare-associated transmission of Panton-Valentine leucocidin positive methicillin-resistant Staphylococcus aureus: the value of screening asymptomatic healthcare workers

Background

Three patients hospitalised in the coronary care unit of a general district hospital (England, UK) were tested positive for Panton-Valentine leucocidin methicillin-resistant Staphylococcus aureus colonisation during their routine weekly screening for methicillin-resistant Staphylococcus aureus (MRSA). The isolates were indistinguishable and all three patients have previously had negative screening tests. The outbreak investigation team considered exploring the possibility of PVL-MRSA transmission from members of staff to the patients and potentially between members of staff.

Method

As part of the investigations, healthcare workers on coronary care unit and intensive care unit were screened for MRSA carriage.

Results

Among 134 screened healthcare workers, five staff members (3.7%) were MRSA colonised. Among these isolates, four were Panton-Valentine leukocidin positive. However, only two healthcare workers had an indistinguishable isolate with the isolate identified among the colonised patients. Decolonisation treatment was offered to all colonised patients and healthcare workers.

Conclusion

In low MRSA prevalence settings, healthcare workers may be a reservoir of MRSA and an important potential source of transmission to patients. Screening and decolonisation of colonised healthcare workers may provide a valuable strategy in managing linked hospital acquisitions and reduce the risk of occupationally acquired complications. MRSA mass screen of healthcare workers should be considered in transmission with a strain that has a potentially increased virulence, such as Panton-Valentine leucocidin methicillin-resistant Staphylococcus aureus.

Epidemiology and risk factors for recurrent Staphylococcus aureus colonization following active surveillance and decolonization in the NICU

OBJECTIVES

To examine neonatal risk factors associated with recurrent Staphylococcus aureus colonization and to determine the genetic relatedness of S. aureus strains cultured from neonates before and after decolonization.Study designSingle-center retrospective cohort study of neonates admitted to the neonatal intensive care unit (NICU) from April 2013 to December 2015, during which weekly nasal cultures from hospitalized NICU patients were routinely obtained for S. aureus surveillance.

SETTING

Johns Hopkins Hospital's 45-bed level IV NICU in Baltimore, Maryland.

METHODS

Demographics and clinical data were collected on all neonates admitted to the NICU with S. aureus nasal colonization who underwent mupirocin-based decolonization during the study period. A decolonized neonate was defined as a neonate with ≥1 negative culture after intranasal mupirocin treatment. Pulsed-field gel electrophoresis was used for strain typing.

RESULTS

Of 2,060 infants screened for S. aureus, 271 (13%) were colonized, and 203 of these 271 (75%) received intranasal mupirocin. Of those treated, 162 (80%) had follow-up surveillance cultures, and 63 of these 162 infants (39%) developed recurrent colonization after treatment. The S. aureus strains were often genetically similar before and after decolonization. The presence of an endotracheal tube or nasal cannula/mask was associated with an increased risk of recurrent S. aureus colonization (hazard ratio [HR], 2.65; 95% confidence interval [CI], 1.19-5.90; and HR, 2.21; 95% CI, 1.02-4.75, respectively).

CONCLUSION

Strains identified before and after decolonization were often genetically similar, and the presence of invasive respiratory devices increased the risk of recurrent S. aureus nasal colonization in neonates. To improve decolonization efficacy, alternative strategies may be needed.

Development of Antibacterial and Antifungal Triazole Chromium(III) and Cobalt(II) Complexes: Synthesis and Biological Activity Evaluations

In this work, six complexes (2⁻7) of Cr(III) and Co(II) transition metals with triazole ligands were synthesized and characterized. In addition, a new ligand, 3,5-bis(1,2,4-triazol-1-ylmethyl)toluene (1), was synthesized and full characterized. The complexes were obtained as air-stable solids and characterized by melting point, electrical conductivity, thermogravimetric analysis, and Raman, infrared and ultraviolet/visible spectroscopy. The analyses and spectral data showed that complexes 3⁻7 had 1:1 (M:L) stoichiometries and octahedral geometries, while 2 had a 1:2 (M:L) ratio, which was supported by DFT calculations. The complexes and their respective ligands were evaluated against bacterial and fungal strains with clinical relevance. All the complexes showed higher antibacterial and antifungal activities than the free ligands. The complexes were more active against fungi than against bacteria. The activities of the chromium complexes against Candida tropicalis are of great interest, as they showed minimum inhibitory concentration 50 (MIC₅₀) values between 7.8 and 15.6 μg mL^-1. Complexes 5 and 6 showed little effect on Vero cells, indicating that they are not cytotoxic. These results can provide an important platform for the design of new compounds with antibacterial and antifungal activities.

Evaluating a neonatal intensive care unit MRSA surveillance programme using agent-based network modelling

BACKGROUND

Surveillance for meticillin-resistant Staphylococcus aureus (MRSA) in neonatal intensive care units (NICUs) is a commonplace infection prevention strategy, yet the optimal frequency with which to monitor the unit is unknown.

AIM

To compare various surveillance frequencies using simulation modelling.

METHODS

One hundred NICU networks of 52 infants were simulated over a six-month period to assess MRSA transmission. Unit-wide surveillance occurred every N weeks where N={1,2,3,4}, and was compared with the current NICU policy of dynamic surveillance (i.e. weekly when at least one positive screen, otherwise every three weeks). For each surveillance period, colonized infants received a decolonization regimen (56% effective) and were moved to isolation rooms, if available.

FINDINGS

As the surveillance frequency increased, the mean number of MRSA-colonized infants decreased, from a high of 2.9 (four-weekly monitoring) to a low of 0.6 (weekly monitoring) detected per episode. The mean duration of colonization decreased from 307 h (four-weekly monitoring) to 61 h (weekly monitoring). Meanwhile, the availability of isolation rooms followed an inverse relationship: as surveillance frequency increased, the availability of isolation rooms decreased (61% isolation success rate for four-weekly monitoring vs 49% success rate for weekly monitoring). The dynamic policy performed similar to a biweekly programme.

CONCLUSIONS

An effective MRSA surveillance programme needs to balance resource availability with potential for harm due to longer colonization periods and opportunity for development of invasive disease. While more frequent monitoring led to greater use of a decolonization regimen, it also reduced the likelihood of isolation rooms being available.

New Threats from an Old Foe: Methicillin-Resistant Staphylococcus aureus Infections in Neonates

Methicillin-resistant Staphylococcus aureus (MRSA) is a ubiquitous human inhabitant and one of the important pathogens of neonatal infections. MRSA is associated with significant mortality and morbidity, especially in very immature preterm neonates. Moreover, MRSA may be implicated in adverse long-term neonatal outcomes, posing a substantial disease burden. Recent advances in molecular microbiology have shed light on the evolution of MRSA population structure and virulence factors, which may contribute to MRSA epidemic waves worldwide. Equipped with remarkable genetic flexibility, MRSA has successfully developed resistance to an extensive range of antibiotics including vancomycin, as well as antiseptics. In the face of these new challenges from MRSA, our armamentarium of anti-infective strategies is very limited and largely dependent on prevention measures. Active surveillance cultures followed by decolonization may be a promising approach to control MRSA infections, with its efficacy and safety in the specific population of neonates yet to be addressed by large multicenter studies.

Preventing Transmission of Multidrug-Resistant Pathogens in the Intensive Care Unit

Infection control in the intensive care unit (ICU) has seen many advances, including rapid molecular screening tests for resistant organisms and chlorhexidine use in daily baths. Although these developments advance the cause of infection prevention, compliance with some of the basic measures remains elusive. Hand hygiene, antimicrobial stewardship, and reduction in device use remain the low-technology interventions that could have a major impact on nosocomial transmission of antimicrobial-resistant organisms. Although continued research is needed on new and old ways of preventing nosocomial infections, ICU staff must persevere in improving adherence with the measures that are known to be effective.

Bacterial Infections in Neonates Following Mupirocin-Based MRSA Decolonization: A Multicenter Cohort Study

OBJECTIVE To characterize the risk of infection after MRSA decolonization with intranasal mupirocin. DESIGN Multicenter, retrospective cohort study. SETTING Tertiary care neonatal intensive care units (NICUs) from 3 urban hospitals in the United States ranging in size from 45 to 100 beds. METHODS MRSA-colonized neonates were identified from NICU admissions occurring from January 2007 to December 2014, during which a targeted decolonization strategy was used for MRSA control. In 2 time-to-event analyses, MRSA-colonized neonates were observed from the date of the first MRSA-positive surveillance screen until (1) the first occurrence of novel gram-positive cocci in sterile culture or discharge or (2) the first occurrence of novel gram-negative bacilli in sterile culture or discharge. Mupirocin exposure was treated as time varying. RESULTS A total of 522 MRSA-colonized neonates were identified from 16,144 neonates admitted to site NICUs. Of the MRSA-colonized neonates, 384 (74%) received mupirocin. Average time from positive culture to mupirocin treatment was 3.5 days (standard deviation, 7.2 days). The adjusted hazard of gram-positive cocci infection was 64% lower among mupirocin-exposed versus mupirocin-unexposed neonates (hazard ratio, 0.36; 95% confidence interval [CI], 0.17-0.76), whereas the adjusted hazard ratio of gram-negative bacilli infection comparing mupirocin-exposed and -unexposed neonates was 1.05 (95% CI, 0.42-2.62). CONCLUSIONS In this multicentered cohort of MRSA-colonized neonates, mupirocin-based decolonization treatment appeared to decrease the risk of infection with select gram-positive organisms as intended, and the treatment was not significantly associated with risk of subsequent infections with organisms not covered by mupirocin's spectrum of activity. Infect Control Hosp Epidemiol 2017;38:930-936.

Neonatal methicillin-resistant Staphylococcus aureus colonization and infection

INTRODUCTION

Methicillin-resistant Staphylococcus aureus (MRSA) is a common etiological agent of a life-threatening infection in neonatal intensive care units (NICUs). Neonates with very low birth weight and patients with serious diseases are more likely to be exposed to invasive procedures which make them at a high risk of MRSA colonization and infection. Since MRSA colonization is a risk factor for MRSA infection, prevention of MRSA transmission is an important issue in NICUs. NICUs in Japan practice standard contact precautions and active surveillance cultures (ASC) to prevent MRSA transmission. In this report, we analyzed the clinical characteristics of MRSA colonization and infection between January 2010 and December 2015 in our perinatal care center.

METHODS

We conducted retrospective analysis of 1716 neonates hospitalized in our perinatal care center.

RESULTS

120 cases had MRSA colonization (6.99%) and among them 33 neonates were infected. The duration of stay (P≤0.001) and the birth weight (P≤0.001) showed statistically significant differences between MRSA-colonized neonates and non-MRSA-colonized neonates. The number of central venous catheterization showed statistically significant differences (P = 0.001) and the number of digestive system diseases showed marginally significant differences (P = 0.072) between MRSA-colonized non-infected neonates and MRSA-infected neonates.

CONCLUSIONS

As previous reports have shown, we present that the neonates with central venous catheterization were more likely to be infected with MRSA. We also need to pay attention to neonates with digestive system diseases, showing signs of infection, because they may be potentially infected with MRSA.