Sources and reservoirs of Staphylococcus capitis NRCS-A inside a NICU

Trends in viable microbial bioburden on surfaces within a paediatric bone marrow transplant unit

BACKGROUND

Despite their role being historically overlooked, environmental surfaces have been shown to play a key role in the transmission of pathogens causative of healthcare-associated infection. To guide infection prevention and control (IPC) interventions and inform clinical risk assessments, more needs to be known about microbial surface bioburdens.

AIM

To identify the trends in culturable bacterial contamination across communal touch sites over time in a hospital setting.

METHODS

Swab samples were collected over nine weeks from 22 communal touch sites in a paediatric bone marrow transplant unit. Samples were cultured on Columbia blood agar and aerobic colony counts (ACC) per 100 cm2 were established for each site. Individual colony morphologies were grouped and identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry or 16s rDNA sequencing.

FINDINGS

Highest mean counts were observed for sites associated with ward management activity and computer devices (3.29 and 2.97 ACC/100 cm2 respectively). A nurses' station keyboard had high mean ACC/100 cm2 counts (10.67) and diversity, while laundry controls had high mean ACC/100 cm2 counts (4.70) and low diversity. Micrococcus luteus was identified in all sampling groups. Clinical staff usage sites were contaminated with similar proportions of skin and environmental flora (52.19-46.59% respectively), but sites associated with parental activities were predominantly contaminated by environmental microflora (86.53%).

CONCLUSION

The trends observed suggest patterns in microbial loading based on site activities, surface types and user groups. Improved understanding of environmental surface contamination could help support results interpretation and IPC interventions, improving patient safety.

The use of ultraviolet light generated from light-emitting diodes for the disinfection of transvaginal ultrasound probes

Transvaginal ultrasound probes (TVUS) are used for several gynecological procedures. These need to be disinfected between patient use. In the current study we examine whether UVC delivered using light emitting diodes for 90 seconds can provide sufficient disinfection efficacy. A new UVC device that delivers UVC radiation at 265nm-275nm for 90 seconds was used. TVUS probes were swabbed before and after use in an in vitro fertilization clinic. Microbes on the swabs were cultured and identified. In addition, the ability of the UVC device to provided repeated high-level disinfection was analysed by deliberately contaminating probes with spores of Bacillus subtilis and then performing the UVC disinfection and bacterial culture. 50% of probes were contaminated with bacteria, most commonly Bacillus sp., directly after in vivo use. Whereas 97% were sterile after UVC disinfection for 90 seconds. The UVC treatment resulted in no growth of B. subtilis spores after each of five repeated contaminations with 5-9 x 107 spores on the probes. This study has found that UVC delivered via light emitting diodes for only 90 seconds can produce high level disinfection of transvaginal probes.

Staphylococcus capitis Bloodstream Isolates: Investigation of Clonal Relationship, Resistance Profile, Virulence and Biofilm Formation

Staphylococcus capitis has been recognized as a relevant opportunistic pathogen, particularly its persistence in neonatal ICUs around the world. Therefore, the aim of this study was to describe the epidemiological profile of clinical isolates of S. capitis and to characterize the factors involved in the persistence and pathogenesis of these strains isolated from blood cultures collected in a hospital in the interior of the state of São Paulo, Brazil. A total of 141 S. capitis strains were submitted to detection of the mecA gene and SCCmec typing by multiplex PCR. Genes involved in biofilm production and genes encoding enterotoxins and hemolysins were detected by conventional PCR. Biofilm formation was evaluated by the polystyrene plate adherence test and phenotypic resistance was investigated by the disk diffusion method. Finally, pulsed-field gel electrophoresis (PFGE) was used to analyze the clonal relationship between isolates. The mecA gene was detected in 99 (70.2%) isolates, with this percentage reaching 100% in the neonatal ICU. SCCmec type III was the most prevalent type, detected in 31 (31.3%) isolates and co-occurrence of SCCmec was also observed. In vitro biofilm formation was detected in 46 (32.6%) isolates but was not correlated with the presence of the ica operon genes. Furthermore, biofilm production in ICU isolates was favored by hyperosmotic conditions, which are common in ICUs because of the frequent parenteral nutrition. Analysis of the clonal relationship between the isolates investigated in the present study confirms a homogeneous profile of S. capitis and the persistence of clones that are prevalent in the neonatal ICU and disseminated across the hospital. This study highlights the adaptation of isolates to specific hospital environments and their high clonality.

Detection of clinically relevant antibiotic-resistant bacteria in shared fomites, waste water and municipal solid wastes disposed near residential areas of a Nigerian city

Studies investigating environmental hotspots of antibiotic-resistant bacteria (ARB) and antibiotic resistance genes (ARGs) in Nigeria are limited. This study was designed to assess various environmental sources and commonly touched surfaces as potential carriers of ARB and ARGs with implications for public health. A total of 392 samples, including sewage (36), sludge (36), diapers (20), plastics (20), water sachet polythene bags (20), food wastes (20), soil beneath dump sites (20), and frequently touched surfaces such as restroom floors (80), corridors (24), door handles (56), and room floors and walls (60), were collected and screened for the presence of resistant bacteria carrying genes such as bla KPC, bla NDM-1, bla CMY-2, bla IMP, bla OXA66 and MecA. Additionally, we employed standard techniques to detect methicillin-resistant Staphylococcus aureus (MRSA) and extended-spectrum β-lactamase (ESBL)-producing Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa and Acinetobacter baumannii . We also evaluated the effectiveness of routine disinfection procedures in eliminating ARB from restroom floors. Our findings revealed that sewage, sludge, diapers, food wastes and restroom floors are frequently contaminated with highly and moderately resistant strains of E. coli, K. pneumoniae, P. aeruginosa and MRSA. Notably, we identified two variants of the bla OXA51-like gene (bla OXA-66 and bla OXA-180) in A. baumannii isolated from these environmental sources. Furthermore, we detected seven ESBL- K. pneumoniae , five ESBL- A. baumannii , two ESBL- E. coli and one ESBL- P. aeruginosa , all carrying one or more ARGs (bla KPC, bla NDM-1, bla CMY-2), in isolates recovered from sewage, sludge, restroom floors and plastics. It is of note that ARB persisted on restroom floors even after disinfection procedures. In conclusion, this study highlights that environmental wastes indiscriminately discarded in residential areas and shared surfaces among individuals are heavily colonized by ARB carrying ARGs of significant public health importance.

Characterisation of neonatal Staphylococcus capitis NRCS-A isolates compared with non NRCS-A Staphylococcus capitis from neonates and adults

Staphylococcus capitis is a frequent cause of late-onset sepsis in neonates admitted to Neonatal Intensive Care Units (NICU). One clone of S. capitis, NRCS-A has been isolated from NICUs globally although the reasons for the global success of this clone are not well understood.We analysed a collection of S. capitis colonising babies admitted to two NICUs, one in the UK and one in Germany as well as corresponding pathological clinical isolates. Genome analysis identified a population structure of three groups; non-NRCS-A isolates, NRCS-A isolates, and a group of 'proto NRCS-A' - isolates closely related to NRCS-A but not associated with neonatal infection. All bloodstream isolates belonged to the NRCS-A group and were indistinguishable from strains carried on the skin or in the gut. NRCS-A isolates showed increased tolerance to chlorhexidine and antibiotics relative to the other S. capitis as well as enhanced ability to grow at higher pH values. Analysis of the pangenome of 138 isolates identified characteristic nsr and tarJ genes in both the NRCS-A and proto groups. A CRISPR-cas system was only seen in NRCS-A isolates which also showed enrichment of genes for metal acquisition and transport.We found evidence for transmission of S. capitis NRCS-A within NICU, with related isolates shared between babies and multiple acquisitions by some babies. Our data show NRCS-A strains commonly colonise uninfected babies in NICU representing a potential reservoir for potential infection. This work provides more evidence that adaptation to survive in the gut and on skin facilitates spread of NRCS-A, and that metal acquisition and tolerance may be important to the biology of NRCS-A. Understanding how NRCS-A survives in NICUs can help develop infection control procedures against this clone.

Detection, survival, and persistence of Staphylococcus capitis NRCS-A in neonatal units in England

BACKGROUND

The multidrug-resistant Staphylococcus capitis clone, NRCS-A, is increasingly associated with late-onset sepsis in low birthweight newborns in neonatal intensive care units (NICUs) in England and globally. Understanding where this bacterium survives and persists within the NICU environment is key to developing and implementing effective control measures.

AIM

To investigate the potential for S. capitis to colonize surfaces within NICUs.

METHODS

Surface swabs were collected from four NICUs with and without known NRCS-A colonizations/infections present at the time of sampling. Samples were cultured and S. capitis isolates analysed via whole-genome sequencing. Survival of NRCS-A on plastic surfaces was assessed over time and compared to that of non-NRCS-A isolates. The bactericidal activity of commonly used chemical disinfectants against S. capitis was assessed.

FINDINGS

Of 173 surfaces sampled, 40 (21.1%) harboured S. capitis with 30 isolates (75%) being NRCS-A. Whereas S. capitis was recovered from surfaces across the NICU, the NRCS-A clone was rarely recovered from outside the immediate neonatal bedspace. Incubators and other bedside equipment were contaminated with NRCS-A regardless of clinical case detection. In the absence of cleaning, S. capitis was able to survive for three days with minimal losses in viability (<0.5 log10 reduction). Sodium troclosene and a QAC-based detergent/disinfectant reduced S. capitis to below detectable levels.

CONCLUSION

S. capitis NRCS-A can be readily recovered from the NICU environment, even in units with no recent reported clinical cases of S. capitis infection, highlighting a need for appropriate national guidance on cleaning within the neonatal care environment.

Whole-genome sequencing reveals widespread presence of Staphylococcus capitis NRCS-A clone in neonatal units across the United Kingdom

OBJECTIVE

Increased incidence of neonatal Staphylococcus capitis bacteraemia in summer 2020, London, raised suspicion of widespread multidrug-resistant clone NRCS-A. We set out to investigate the molecular epidemiology of this clone in neonatal units (NNUs) across the UK.

METHODS

We conducted whole-genome sequencing (WGS) on presumptive S. capitis NRCS-A isolates collected from infants admitted to nationwide NNUs and from environmental sampling in two distinct NNUs in 2021. Previously published S. capitis genomes were added for comparison. Genetic clusters of NRCS-A isolates were defined based on core-genome single-nucleotide polymorphisms.

RESULTS

We analysed WGS data of 838 S. capitis isolates and identified 750 NRCS-A isolates. We discovered a possible UK-specific NRCS-A lineage consisting of 611 isolates collected between 2005 and 2021. We determined 28 genetic clusters of NRCS-A isolates, which covered all geographical regions in the UK, and isolates of 19 genetic clusters were found in ≥2 regions, suggesting inter-regional spread. Within the NRCS-A clone, strong genetic relatedness was identified between contemporary clinical and incubator-associated fomite isolates and between clinical isolates associated with inter-hospital infant transfer.

CONCLUSIONS

This WGS-based study confirms the dispersion of S. capitis NRCS-A clone amongst NNUs across the UK and urges research on improving clinical management of neonatal S. capitis infection.

Using adenosine triphosphate bioluminescence level monitoring to identify bacterial reservoirs during two consecutive Enterococcus faecium and Staphylococcus capitis nosocomial infection outbreaks at a neonatal intensive care unit

INTRODUCTION

This study aimed to assess the role of adenosine triphosphate (ATP) bioluminescence level monitoring for identifying reservoirs of the outbreak pathogen during two consecutive outbreaks caused by Enterococcus faecium and Staphylococcus capitis at a neonatal intensive care unit (NICU). The secondary aim was to evaluate the long-term sustainability of the infection control measures employed one year after the final intervention measures.

METHODS

Two outbreaks occurred during a 53-day period in two disconnected subunits, A and B, that share the same attending physicians. ATP bioluminescence level monitoring, environmental cultures, and hand cultures from healthcare workers (HCW) in the NICU were performed. Pulsed-field gel electrophoresis (PFGE) typing was carried out to investigate the phylogenetic relatedness of the isolated strains.

RESULTS

Four cases of E. faecium sepsis (patients A-8, A-7, A-9, B-8) and three cases of S. capitis sepsis (patients A-16, A-2, B-8) were diagnosed in six preterm infants over a span of 53 days. ATP levels remained high on keyboard 1 of the main station (2076 relative light unit [RLU]/100 cm2) and the keyboard of bed A-9 (4886 RLU/100 cm2). By guidance with the ATP results, environmental cultures showed that E. faecium isolated from the patients and from the main station's keyboard 1 were genotypically indistinguishable. Two different S. capitis strains caused sepsis in three patients. A total 77.8% (n = 7/9) of S. capitis cultured from HCW's hands were genotypically indistinguishable to the strains isolated from A-2 and A-16. The remaining 22.2% (n = 2/9) were genotypically indistinguishable to patient B-8. Three interventions to decrease the risk of bacterial transmission were applied, with the final intervention including a switch of all keyboards and mice in NICU-A and B to disinfectable ones. Post-intervention prospective monitoring up to one year showed a decrease in blood culture positivity (P = 0.0019) and catheter-related blood stream infection rate (P = 0.016) before and after intervention.

CONCLUSION

ATP monitoring is an effective tool in identifying difficult to disinfect areas in NICUs. Non-medical devices may serve as reservoirs of pathogens causing nosocomial outbreaks, and HCWs' hands contribute to bacterial transmission in NICUs.

Staphylococcus capitis: Review of Its Role in Infections and Outbreaks

In June 2021, a national incident team was formed due to an increased detection of Staphylococcus capitis in samples from hospitalised infants. Staphylococcus capitis has been known to cause outbreaks in neonatal units across the globe, but the extent of the UK spread was unclear. A literature review was undertaken to support case identification, clinical management and environmental infection control. A literature search was undertaken on multiple databases from inception to 24 May 2021, using keywords such as “Staphylococcus capitis”, “NRCS-A”, “S. capitis”, “neonate”, “newborn” and “neonatal intensive care unit” (NICU). After screening, 223 articles of relevance were included. Results show incidences of S. capitis outbreaks have frequently been associated with the outbreak clone (NRCS-A) and environmental sources. The NRCS-A harbours a multidrug resistance profile that includes resistance to beta-lactam antibiotics and aminoglycosides, with several papers noting resistance or heteroresistance to vancomycin. The NRCS-A clone also harbours a novel SCCmec-SCCcad/ars/cop composite island and increased vancomycin resistance. The S. capitis NRCS-A clone has been detected for decades, but the reasons for the potentially increased frequency are unclear, as are the most effective interventions to manage outbreaks associated with this clone. This supports the need for improvements in environmental control and decontamination strategies to prevent transmission.

Disinfection of incubators in neonatal intensive care units: impact of steam pulverization on bacterial colonization

BACKGROUND

In neonatal intensive care units (NICUs), neonates requiring medical care after birth, including very vulnerable preterm infants, are housed in incubators. Previous studies have reported that the standard chemical disinfection measures used to disinfect these incubators are insufficient to eradicate contaminating bacteria, leading to a worrying infectious risk for preterm neonates. This study aimed to evaluate the efficacy of a disinfection method based on steam pulverization to eradicate the persistent bacterial contamination in such incubators.

METHODS

In a tertiary NICU, 20 incubators were monitored qualitatively for bacterial contamination at five different sites (the rubber grommet, the left door handles, the temperature adjustment button, the mattress and the scale) using a culture method at three times: before and after steam pulverization then 24 h after turning on and housing a new neonate. Clinical data of neonates housed in each incubator were retrieved from the medical records to identify potential occurrence of late onset sepsis (LOS).

RESULTS

Just after steam pulverization, only two incubators were free from bacteria. Before disinfection 87% of all the samples were contaminated compared to 61% after disinfection. After 24 h, the proportion of contaminated samples reached 85%. Mattresses and scales were the most frequently contaminated incubator sites with respectively 90% and 80% positive samples after disinfection compared to 100% and 90% before disinfection. Coagulase-negative staphylococci, Enterococcus, Enterobacteria and Bacillus resisted disinfection and were identified on respectively 90%, 20%, 5% and 45% of incubators just after disinfection. Three preterm neonates developed LOS after being housed in a disinfected incubator but the bacterial species involved have not been identified in their incubator after disinfection. In two cases, the bacterium had been isolated from the mattress 24 h after housing the infected patient.

CONCLUSION

Steam pulverization is not sufficient to eradicate bacterial contamination of incubators. These results highlight the urgent need for an effective disinfection method, especially for mattresses that are in constant contact with patients. In parallel, new incubator designs and mattress protections must be developed.

Environmental Persistence of Staphylococcus capitis NRCS-A in Neonatal Intensive Care Units: Role of Biofilm Formation, Desiccation, and Disinfectant Tolerance

The clone Staphylococcus capitis NRCS-A is responsible for late-onset sepsis in neonatal intensive care units (NICUs) worldwide. Over time, this clone has evolved into three subgroups that are increasingly adapted to the NICU environment. This study aimed to decipher the mechanisms involved in NRCS-A persistence in NICUs. Twenty-six S. capitis strains belonging to each of the three NRCS-A clone subgroups and two other non-NRCS-A groups from neonates (alpha clone) or from adult patients ("other strains") were compared based on growth kinetics and ability to form biofilm as well as tolerance to desiccation and to different disinfectants. S. capitis biofilm formation was enhanced in rich medium and decreased under conditions of nutrient stress for all strains. However, under conditions of nutrient stress, NRCS-A strains presented an enhanced ability to adhere and form a thin biofilm containing more viable and culturable bacteria (mean 5.7 log10 CFU) than the strains from alpha clone (mean, 1.1 log10 CFU) and the "other strains" (mean, 4.2 log10 CFU) (P < 0.0001). The biofilm is composed of bacterial aggregates with a matrix mainly composed of polysaccharides. The NRCS-A clone also showed better persistence after a 48-h desiccation. However, disinfectant tolerance was not enhanced in the NRCS-A clone in comparison with that of strains from adult patients. In conclusion, the ability to form biofilm under nutrient stress and to survive desiccation are two major advantages for clone NRCS-A that could explain its ability to persist and settle in the specific environment of NICU settings. IMPORTANCE Neonatal intensive care units (NICUs) host extremely fragile newborns, including preterm neonates. These patients are very susceptible to nosocomial infections, with coagulase-negative staphylococci being the species most frequently involved. In particular, a Staphylococcus capitis clone named NRCS-A has emerged worldwide specifically in NICUs and is responsible for severe nosocomial sepsis in preterm neonates. This clone is specifically adapted to the NICU environment and is able to colonize and maintain on NICU surfaces. The present work explored the mechanisms involved in the persistence of the NRCS-A clone in the NICU environment despite strict hygiene measures. The ability to produce biofilm under nutritional stress and to resist desiccation appear to be the two main advantages of NRCS-A in comparison with other strains. These findings are pivotal to provide clues for subsequent development of targeted methods to combat NRCS-A and to stop its dissemination.

Bacteriophage-based decontamination to control environmental colonization by Staphylococcus capitis in neonatal intensive care units: An in vitro proof-of-concept

Introduction

In neonatal intensive care units (NICUs), the standard chemical-based disinfection procedures do not allow a complete eradication of pathogens from environmental surfaces. In particular, the clone Staphylococcus capitis NRCS-A, a significant pathogen in neonates, was shown to colonize neonatal incubators. The aim of this study was to evaluate the in vitro effect of a bacteriophage cocktail on NRCS-A eradication.

Methods

Three bacteriophages were isolated, genetically characterized and assessed for their host range using a collection of representative clinical strains (n=31) belonging to the clone NRCS-A. The efficacy of a cocktail including these three bacteriophages to eradicate the reference strain S. capitis NRCS-A CR01 was determined in comparison or in combination with the chemical disinfectant Surfanios Premium on either dry inoculum or biofilm-embedded bacteria. The emergence of bacterial resistance against the bacteriophages alone or in cocktail was evaluated by growth kinetics.

Results

The three bacteriophages belonged to two families and genera, namely Herelleviridae/Kayvirus for V1SC01 and V1SC04 and Rountreeviridae/Andhravirus for V1SC05. They were active against 17, 25 and 16 of the 31 tested strains respectively. Bacteriophage cocktails decreased the bacterial inoculum of both dry spots and biofilms, with a dose dependent effect. The sequential treatment with bacteriophages then Surfanios Premium did not show enhanced efficacy. No bacterial resistance was observed when using the bacteriophage cocktail.

Discussion

This study established a proof-of-concept for the use of bacteriophages to fight against S. capitis NRCS-A. Further investigations are needed using a larger bacterial collection and in real-life conditions before being able to use such technology in NICUs

Genetic Characterization of Staphylococcus aureus, Staphylococcus argenteus, and Coagulase-Negative Staphylococci Colonizing Oral Cavity and Hand of Healthy Adults in Northern Japan

The spread of methicillin resistance and virulence among staphylococci in the community poses a public health concern. In this study, we investigated the prevalence of Staphylococcus species colonizing the oral cavity and hand (skin) of healthy university students and their phenotypic and genetic characteristics in northern Japan. Among a total of 332 subjects, 6 and 110 methicillin-resistant and susceptible Staphylococcus aureus (MRSA and MSSA, respectively) isolates were recovered from 105 subjects. MRSA isolates were genotyped as CC5, CC8, CC45, and CC59 with SCCmec-IIa or IV, among which an isolate of ST6562 (single-locus variant of ST8) harbored SCCmec-IVa, PVL genes and ACME-I, which are the same traits as the USA300 clone. ST1223 S. argenteus was isolated from the oral cavity and hand of a single student. Coagulase-negative Staphylococcus (CoNS) was recovered from 154 subjects (172 isolates), and classified into 17 species, with S. capitis being the most common (38%), followed by S. warneri (24%) and S. epidermidis (15%), including nine mecA-positive isolates. S. capitis was differentiated into seven clusters/subclusters, and genetic factors associated with the NRCS-A clone (nsr, tarJ, ebh) were detected in 10–21% of isolates. The colonization of the USA300-like MRSA variant and S. capitis with the traits of the NRCS-A clone in healthy individuals was noteworthy.

Endogenous endophthalmitis caused by Staphylococcus capitis

Purpose

To report a rare case of endogenous endophthalmitis caused by Staphylococcus capitis.

Observation

A 34-year-old male patient with a history of gonococcal urethritis and arthritis presented with right endogenous endophthalmitis. Vitreous biopsy culture confirmed Staphylococcus capitis involvement. The patient was treated with pars plana vitrectomy, intravitreal vancomycin, and ceftazidime injections and systemic antibiotics.

Conclusion and importance

Staphylococcus capitis-related endogenous endophthalmitis has rarely been reported in the literature. None of the published reports specifically describe its clinical course and management.

Cefazolin susceptibility of coagulase-negative staphylococci (CoNS) causing late-onset neonatal bacteraemia

BACKGROUND

CoNS bacteraemia causes significant neonatal morbidity. Previous work has suggested that β-lactam antibiotics vary in their binding affinity to PBP2a (produced by the mecA gene) present in most CoNS.

OBJECTIVES

We evaluated cefazolin MICs for CoNS isolated in an Australian neonatal ICU (NICU) and correlated them with isolate genotype and phenotype.

METHODS

Significant blood isolates from 2009 to 2017 were speciated and underwent broth microdilution testing for cefazolin, cefoxitin, oxacillin and flucloxacillin. Correlation with mecA presence and PBP2a expression was evaluated. A selection of Staphylococcus capitis isolates underwent WGS.

RESULTS

The CoNS (n = 99) isolates were confirmed as S. capitis (n = 57), Staphylococcus epidermidis (n = 32), Staphylococcus haemolyticus (n = 2) and Staphylococcus warneri (n = 8). The MIC of cefazolin was ≤2 mg/L for 30% of isolates and 75% had an MIC of ≤8 mg/L (MIC90 = 16 mg/L). This contrasted with MIC90s of cefoxitin, oxacillin and flucloxacillin, which were all ≥32 mg/L. WGS found a number of S. capitis isolates closely related to the globally established NRCS-A clone.

CONCLUSIONS

CoNS displayed distinctly lower MIC values of cefazolin than of other agents tested. MIC variation may be related to binding affinity of PBP2a or regulation of expression of mecA by mecR1-mecI functional genes. Further, NRCS-A S. capitis strains were present in this Australian NICU before and after the unit underwent physical relocation, which raised questions about a common environmental source. It is considered justified to conduct a randomized clinical trial that assesses cefazolin versus vancomycin for management of late-onset neonatal sepsis.

Persistent microbial contamination of incubators despite disinfection

BACKGROUND

In neonatal intensive care units (NICUs), hygiene and disinfection measures are pivotal to protect neonates from nosocomial infections. This study aimed to evaluate the efficacy of the classical incubators disinfection procedure and to follow-up neonates housed in the incubators for the development of late-onset sepsis (LOS).

METHODS

In a tertiary NICU, 20 incubators were monitored for bacterial contamination at three times: before disinfection, after disinfection, and 24 h after turning on and housing a new neonate. Clinical data of neonates housed in these incubators were retrieved from the medical records.

RESULTS

All 20 incubators were contaminated at the 3 times of the study, mainly on mattresses and balances. Coagulase-negative Staphylococci, Enterococcus, and Bacillus-resisted disinfection while enterobacteria and Staphylococcus aureus were eradicated. After 24 h, the bacterial colonisation was similar to the one observed before disinfection. The bacteria isolated on incubators were also found on the caregivers' hands. During the study, two preterm neonates developed a LOS involving a bacterial species that has been previously isolated in their incubator.

CONCLUSION

Pathogenic contaminants persist on incubators despite disinfection and represent a risk for subsequent infection in preterm neonates. Improvements are needed concerning both the disinfection process and incubator design.

IMPACT

Procedures of disinfection that are usually recommended in NICUs do not allow for totally eradicating bacteria from incubators. Preterm neonates are housed in incubators colonised with potentially pathogenic bacteria. The control of nosocomial infections in NICUs requires further researches concerning mechanisms of bacterial persistence and ways to fight against environmental colonisation.

Evidence Map and Systematic Review of Disinfection Efficacy on Environmental Surfaces in Healthcare Facilities

Healthcare-associated infections (HAIs) contribute to patient morbidity and mortality with an estimated 1.7 million infections and 99,000 deaths costing USD $28-34 billion annually in the United States alone. There is little understanding as to if current environmental surface disinfection practices reduce pathogen load, and subsequently HAIs, in critical care settings. This evidence map includes a systematic review on the efficacy of disinfecting environmental surfaces in healthcare facilities. We screened 17,064 abstracts, 635 full texts, and included 181 articles for data extraction and study quality assessment. We reviewed ten disinfectant types and compared disinfectants with respect to study design, outcome organism, and fourteen indictors of study quality. We found important areas for improvement and gaps in the research related to study design, implementation, and analysis. Implementation of disinfection, a determinant of disinfection outcomes, was not measured in most studies and few studies assessed fungi or viruses. Assessing and comparing disinfection efficacy was impeded by study heterogeneity; however, we catalogued the outcomes and results for each disinfection type. We concluded that guidelines for disinfectant use are primarily based on laboratory data rather than a systematic review of in situ disinfection efficacy. It is critically important for practitioners and researchers to consider system-level efficacy and not just the efficacy of the disinfectant.