Clostridioides difficile detection and infection in children: are they just small adults?

Clostridioides difficile is a well-recognized healthcare-associated pathogen, with its significance widely recognized in adult populations. Despite this, there is limited data on the significance of detection within paediatric populations, both for individual patient management and wider transmission risk-based considerations. High rates of colonization are understood to occur in infants, with increasing levels up to 11 months, and colonization rates similar to adults by 8 years old. Sources of C. difficile are ubiquitous, with detection in companion animals and food sources, as well as within the clinical and wider environment. Due to the close interactions that occur between children and the environment, it is understandable that increasing recognition is afforded to the community acquisition of C. difficile in children. Other risk factors for the detection of C. difficile in children are similar to those observed in adults, including prior hospitalization and underlying conditions affecting gut health and motility. Recent studies have shown rising awareness of the role of asymptomatic carriage of C. difficile in healthcare transmission. Prior to this, paediatric patient populations were less likely to be screened due to uncertainty regarding the significance of detection; however, this increased awareness has led to a review of possible carriage testing pathways. Despite this increased attention, C. difficile infection remains poorly defined in paediatric populations, with limited dedicated paediatric data sets making comparison challenging. This is further complicated by the fact that infection in children frequently self resolves without additional therapies. Due to this, C. difficile remains a management challenge in paediatric settings.

Using Whole Genome Sequences to Investigate Adenovirus Outbreaks in a Hematopoietic Stem Cell Transplant Unit.

A recent surge in human mastadenovirus (HAdV) cases, including five deaths, amongst a haematopoietic stem cell transplant population led us to use whole genome sequencing (WGS) to investigate. We compared sequences from 37 patients collected over a 20-month period with sequences from GenBank and our own database of HAdVs. Maximum likelihood trees and pairwise differences were used to evaluate genotypic relationships, paired with the epidemiological data from routine infection prevention and control (IPC) records and hospital activity data. During this time period, two formal outbreaks had been declared by IPC, while WGS detected nine monophyletic clusters, seven were corroborated by epidemiological evidence and by comparison of single-nucleotide polymorphisms. One of the formal outbreaks was confirmed, and the other was not. Of the five HAdV-associated deaths, three were unlinked and the remaining two considered the source of transmission. Mixed infection was frequent (10%), providing a sentinel source of recombination and superinfection. Immunosuppressed patients harboring a high rate of HAdV positivity require comprehensive surveillance. As a consequence of these findings, HAdV WGS is being incorporated routinely into clinical practice to influence IPC policy contemporaneously.

Silver-impregnated, antibiotic-impregnated or non-impregnated ventriculoperitoneal shunts to prevent shunt infection: the BASICS three-arm RCT.

BACKGROUND: Insertion of a ventriculoperitoneal shunt to treat hydrocephalus is one of the most common neurosurgical procedures worldwide. Shunt infection affects up to 15% of patients, resulting in long hospital stays, multiple surgeries and reduced cognition and quality of life. OBJECTIVES: The aim of this trial was to determine whether or not antibiotic-impregnated ventriculoperitoneal shunts (hereafter referred to as antibiotic shunts) (e.g. impregnated with rifampicin and clindamycin) or silver-impregnated ventriculoperitoneal shunts (hereafter referred to as silver shunts) reduce infection compared with standard ventriculoperitoneal shunts (hereafter referred to as standard shunts). DESIGN: This was a three-arm, superiority, multicentre, parallel-group randomised controlled trial. Patients and a central primary outcome review panel, but not surgeons or operating staff, were blinded to the type of ventriculoperitoneal shunt inserted. SETTING: The trial was set in 21 neurosurgical wards across the UK and the Republic of Ireland. PARTICIPANTS: Participants were patients with hydrocephalus of any aetiology who were undergoing insertion of their first ventriculoperitoneal shunt. INTERVENTIONS: Participants were allocated 1 : 1 : 1 by pressure-sealed envelope to receive a standard non-impregnated, silver-impregnated or antibiotic-impregnated ventriculoperitoneal shunt at the time of insertion. Ventriculoperitoneal shunts are medical devices, and were used in accordance with the manufacturer's instructions for their intended purpose. MAIN OUTCOME MEASURES: The primary outcome was time to ventriculoperitoneal shunt failure due to infection. Secondary outcomes were time to failure for any cause, reason for failure (infection, mechanical), types of ventriculoperitoneal shunt infection, rate of infection after first clean (non-infected) revision and health economics. Outcomes were analysed by intention to treat. RESULTS: Between 26 June 2013 and 9 October 2017, 1605 patients from neonate to 91 years of age were randomised to the trial: n = 36 to the standard shunt, n = 538 to the antibiotic shunt and n = 531 to the silver shunt. Patients who did not receive a ventriculoperitoneal shunt (n = 4) or who had an infection at the time of insertion (n = 7) were not assessed for the primary outcome. Infection occurred in 6.0% (n = 32/533) of those who received the standard shunt, in 2.2% (n = 12/535) of those who received the antibiotic shunt and in 5.9% (n = 31/526) of those who received the silver shunt. Compared with the standard shunt, antibiotic shunts were associated with a lower rate of infection (cause-specific hazard ratio 0.38, 97.5% confidence interval 0.18 to 0.80) and a decreased probability of infection (subdistribution hazard ratio 0.38, 97.5% confidence interval 0.18 to 0.80). Silver shunts were not associated with a lower rate of infection than standard shunts (cause-specific hazard ratio 0.99, 97.5% confidence interval 0.56 to 1.74). The ventriculoperitoneal shunt failure rate attributable to any cause was 25.0% overall and did not differ between arms. Antibiotic shunts save £135,753 per infection avoided. There were no serious adverse events. LIMITATIONS: It was not possible to blind treating neurosurgeons to the ventriculoperitoneal shunt type. The return rate for patient-reported outcomes was low. Limitations to the economic evaluation included failure to obtain Hospital Episode Statistics data from NHS Digital, as per protocol. Reliance on patient-level information and costing systems data mitigated these limitations. CONCLUSIONS: Antibiotic shunts have a reduced infection rate compared with standard shunts, whereas silver shunts do not. Antibiotic shunts are cost-saving. FUTURE WORK: A sample collection has been established that will enable the study of surrogate markers of ventriculoperitoneal shunt infection in cerebrospinal fluid or blood using molecular techniques. A post hoc analysis to study factors related to shunt failure will be performed as part of a future study. An impact analysis to assess change in practice is planned. TRIAL REGISTRATION: Current Controlled Trials ISRCTN49474281. FUNDING: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 24, No. 17. See the NIHR Journals Library website for further project information.

Hydrocephalus (commonly known as 'water on the brain') is a condition that can affect all age groups, from babies to the elderly. In hydrocephalus, there is an accumulation of the normal brain fluid in the fluid cavities (ventricles) of the brain. Untreated, hydrocephalus can be life-threatening. The most common treatment involves an operation to insert a tube into the swollen ventricles to drain off the excess fluid. This is called a ventriculoperitoneal shunt. In the UK, 3000­3500 shunt operations are performed each year. The main risks of a shunt operation are infection (surgical meningitis) and blockage without infection. Infection results in the need for at least two further surgeries, antibiotic treatment and a prolonged hospital stay (minimum of 2 weeks). Shunt infections can affect mental abilities and can be life-threatening. People who have blockages without infection, on the other hand, usually need only a single operation to replace the blocked part and only a few days in hospital. Two new types of shunt catheter have been introduced to try to reduce shunt infection: antibiotic-impregnated shunts and silver-impregnated shunts. This study was designed to assess whether or not either of these new shunts reduce infection compared with standard shunts. This study also included an analysis of the cost and health benefits of the different shunts used. A total of 1605 children and adults, who were treated in neurosurgical units across the UK and the Republic of Ireland, participated in this study. Consent was provided by all participants in the trial. Each participant had an equal chance of receiving one of the three shunt types. Shunt infection occurred in 6% of participants receiving standard shunts, 5.9% of participants receiving silver-impregnated shunts and 2.2% of participants receiving antibiotic-impregnated shunts. This study has demonstrated a major reduction in shunt infections in new shunts when using antibiotic-impregnated shunts compared with standard or silver-impregnated shunts. A health economic analysis has indicated that antibiotic-impregnated shunts are cost-saving.

Brain abscess in children, a two-centre audit: outcomes and controversies.

OBJECTIVE: The aim of this study was to better characterise clinical presentation, management and outcome in infants and children with brain abscess. METHODS: The authors conducted a retrospective, multicentre study in two national reference centres over a 25-year period (1992-2017). During this period, 116 children and 28 infants (age <1 year) with brain abscess were treated. RESULTS: The median age at diagnosis was 101.5 (range: 13-213) months in children and 1 (0-11) month in infants. Significant differences were observed between children and infants. The most common predisposing factor was meningitis in infants (64% of cases vs 3% in children), while it was otolaryngology-related infection in children (31% of cases vs 3.6% in infants). Infants presented more frequently with fever and meningism compared with children. 115 patients were treated with aspiration and 11 with excision. Reoperation was required in 29 children vs 1 infant. The overall mortality rate was 4% (3.4% for children, 7.1% for infants). At 3-month follow-up, the outcome was favourable in 86% of children vs in 68% of infants. CONCLUSION: There is a clear difference between children and infants with brain abscess in terms of predisposing factors, causative organisms and outcome. Despite surgical drainage and directed antibiotic therapy, 25% of patients with brain abscess require reoperation. Mortality is improved compared with historical series; however, long-term morbidity is significant particularly in the infant population.

Antibiotic or silver versus standard ventriculoperitoneal shunts (BASICS): a multicentre, single-blinded, randomised trial and economic evaluation.

BACKGROUND: Insertion of a ventriculoperitoneal shunt for hydrocephalus is one of the commonest neurosurgical procedures worldwide. Infection of the implanted shunt affects up to 15% of these patients, resulting in prolonged hospital treatment, multiple surgeries, and reduced cognition and quality of life. Our aim was to determine the clinical and cost-effectiveness of antibiotic (rifampicin and clindamycin) or silver shunts compared with standard shunts at reducing infection. METHODS: In this parallel, multicentre, single-blind, randomised controlled trial, we included patients with hydrocephalus of any aetiology undergoing insertion of their first ventriculoperitoneal shunt irrespective of age at 21 regional adult and paediatric neurosurgery centres in the UK and Ireland. Patients were randomly assigned (1:1:1 in random permuted blocks of three or six) to receive standard shunts (standard shunt group), antibiotic-impregnated (0·15% clindamycin and 0·054% rifampicin; antibiotic shunt group), or silver-impregnated shunts (silver shunt group) through a randomisation sequence generated by an independent statistician. All patients and investigators who recorded and analysed the data were masked for group assignment, which was only disclosed to the neurosurgical staff at the time of operation. Participants receiving a shunt without evidence of infection at the time of insertion were followed up for at least 6 months and a maximum of 2 years. The primary outcome was time to shunt failure due the infection and was analysed with Fine and Gray survival regression models for competing risk by intention to treat. This trial is registered with ISRCTN 49474281. FINDINGS: Between June 26, 2013, and Oct 9, 2017, we assessed 3505 patients, of whom 1605 aged up to 91 years were randomly assigned to receive either a standard shunt (n=536), an antibiotic-impregnated shunt (n=538), or a silver shunt (n=531). 1594 had a shunt inserted without evidence of infection at the time of insertion (533 in the standard shunt group, 535 in the antibiotic shunt group, and 526 in the silver shunt group) and were followed up for a median of 22 months (IQR 10-24; 53 withdrew from follow-up). 32 (6%) of 533 evaluable patients in the standard shunt group had a shunt revision for infection, compared with 12 (2%) of 535 evaluable patients in the antibiotic shunt group (cause-specific hazard ratio [csHR] 0·38, 97·5% CI 0·18-0·80, p=0·0038) and 31 (6%) of 526 patients in the silver shunt group (0·99, 0·56-1·74, p=0·96). 135 (25%) patients in the standard shunt group, 127 (23%) in the antibiotic shunt group, and 134 (36%) in the silver shunt group had adverse events, which were not life-threatening and were mostly related to valve or catheter function. INTERPRETATION: The BASICS trial provides evidence to support the adoption of antibiotic shunts in UK patients who are having their first ventriculoperitoneal shunt insertion. This practice will benefit patients of all ages by reducing the risk and harm of shunt infection. FUNDING: UK National Institute for Health Research Health Technology Assessment programme.

Controlling Legionella pneumophila in water systems at reduced hot water temperatures with copper and silver ionization.

BACKGROUND: Hospital-acquired Legionnaires' disease is associated with the presence of Legionella pneumophila in hospital water systems. In the United Kingdom, the Department of Health recommends maintaining hot water temperatures >55°C and cold water temperatures <20°C at the point of delivery to prevent proliferation of L pneumophila in water systems. In this study, we evaluated the efficacy of copper and silver ionization to control L pneumophila at deliberately reduced hot water temperatures (43°C) within a newly installed water system in a new building linked to a large health care facility in the United Kingdom. METHODS: One thousand, five hundred ninety-eight water samples were collected between September 2011 and June 2017. Samples were tested using accredited methods for L pneumophila, copper and silver ion levels, and total viable counts. Energy consumption and water usage data were also collected to permit carbon emission calculations. RESULTS: The results of 1,598 routine samples from September 2011 to June 2017, and the recordings of temperatures at outlets in this facility, demonstrated effective (100%) L pneumophila control throughout the study period with an average hot water temperature of 42°C. The energy savings and reduction of carbon emissions were calculated to amount to 33% and 24%, respectively, compared to an equivalent temperature-controlled system. Water system management interventions were required to achieve consistently adequate levels of copper and silver across outlets. CONCLUSIONS: This study demonstrated that it is possible to control L pneumophila independent of temperature when copper and silver ionization is introduced into a new building in conjunction with an appropriately managed water system.

Use of Whole-Genome Sequencing of Adenovirus in Immunocompromised Pediatric Patients to Identify Nosocomial Transmission and Mixed-Genotype Infection.

Background: Adenoviruses are significant pathogens for the immunocompromised, arising from primary infection or reinfection. Serotyping is insufficient to support nosocomial transmission investigations. We investigate whether whole-genome sequencing (WGS) provides clinically relevant information on transmission among patients in a pediatric tertiary hospital. Methods: We developed a target-enriched adenovirus WGS technique for clinical samples and retrospectively sequenced 107 adenovirus-positive residual diagnostic samples, including viremias (>5 × 104 copies/mL), from 37 patients collected January 2011-March 2016. Whole-genome sequencing was used to determine genotype and for phylogenetic analysis. Results: Adenovirus sequences were recovered from 105 of 107 samples. Full genome sequences were recovered from all 20 nonspecies C samples and from 36 of 85 species C viruses, with partial genome sequences recovered from the rest. Whole-genome phylogenetic analysis suggested linkage of 3 genotype A31 cases and uncovered an unsuspected epidemiological link to an A31 infection first detected on the same ward 4 years earlier. In 9 samples from 1 patient who died, we identified a mixed genotype adenovirus infection. Conclusions: Adenovirus WGS from clinical samples is possible and useful for genotyping and molecular epidemiology. Whole-genome sequencing identified likely nosocomial transmission with greater resolution than conventional genotyping and distinguished between adenovirus disease due to single or multiple genotypes.

Development and implementation of a cleaning standard algorithm to monitor the efficiency of terminal cleaning in removing adenovirus within a pediatric hematopoietic stem cell transplantation unit.

Adenovirus infections within the hematopoietic stem cell transplantation setting can lead to high rates of mortality and hospital-acquired cases have been associated with environmental reservoirs. To establish both location and levels of environmental adenovirus contamination, 48 cubicles containing 794 surfaces were screened postterminal clean over a 4-year period. After initial cleaning 23% of these sites had detectable adenovirus. These data were then used to develop and implement a cleaning standard algorithm for terminal cleaning that was implemented to ensure cubicles were adenovirus-free before the next patient admission.

Biochemical and microbial contamination of surgical devices: a quantitative analysis.

Reusable devices are required to be safety processed prior to patient use, including cleaning and disinfection and sterilization. In developing and testing cleaning processes, it is important to understand the levels of soils typically present on devices after surgical use. Previous soil investigations have focused on microbial contamination levels; less is known about biochemical contamination. In this study, microbial and biochemical contamination on a range of surgical instrumentation after patient use were investigated. Analysis included bacteria levels, total organic carbon, protein, and hemoglobin. The highest levels of soil contamination were caused by protein, in contrast with bacteria levels being a minor component of instrument soiling. This study provides a better understanding of the microbial and biochemical levels of soils that are typically present in used surgical devices. These levels can be used to develop artificial test soils for testing cleaning efficacy under laboratory conditions and to further evaluate patient risks from inadequate cleaning.

Routine monitoring of adenovirus and norovirus within the health care environment.

This study investigated the presence of adenovirus and norovirus on ward surfaces using real-time polymerase chain reaction (PCR) to assist in the development of evidence-based infection control policy. Screening was carried out weekly for 6 months in the common areas of 2 pediatric wards. Additionally, a one-off screening was undertaken for adenovirus and norovirus on a day unit and for adenovirus only in patient cubicles while occupied. Over the 6-month screening of common areas, 2.4% of samples were positive for adenovirus or norovirus. In rooms occupied with adenovirus-infected children, all cubicle screening sites and almost all swabs were contaminated with adenovirus. In the day unit, 13% of samples were positive. Cleaning and environmental interaction strategies must therefore be designed to control nosocomial transmission of viruses outside of outbreak scenarios.

How clean is clean--is a new microbiology standard required?

The role of environment in the spread of nosocomial infection has been acknowledged. One way to control the spread of infection is to control and monitor patient environments to prevent transmission. Studies applying the suggested aerobic colony count standards to monitor environmental contamination were undertaken over an 18-month period at both a London pediatric hospital and in adult intensive care units. The resulting data demonstrate that a large proportion of sites screened for bacterial contamination would fail if using the criteria suggested by previous authors-particularly those sites closest to patients-suggesting a new standard might be required.

Molecular techniques for diagnosing prosthetic joint infections.

Prosthetic joint infections (PJI) can be broadly classed into two groups: those where there is a strong clinical suspicion of infection and those with clinical uncertainty, including 'aseptic loosening'. Confirmation of infection and identification of the causative organism along with provision of antibiotic susceptibility data are important stages in the management of PJI. Conventional microbiological culture and susceptibility testing is usually sufficient to provide this. However, it may fail due to prior antimicrobial treatment or the presence of unusual and fastidious organisms. Molecular techniques, in particular specific real-time and broad-range PCR, are available for diagnostic use in suspected PJI. In this review, we describe the techniques available, their current strengths, limitations and future development. Real-time pathogen-specific and broad-range PCR (with single sequence determination) are suitable for use as part of the routine diagnostic algorithm for clinically suspected PJI. Further development of broad-range PCR with high-throughput (next-generation) sequencing is necessary to understand the microbiome of the prosthetic joint further before this technique can be used for routine diagnostics in clinically unsuspected PJI, including aseptic loosening.

Long subcutaneous tunnelling reduces infection rates in paediatric external ventricular drains.

PURPOSE: The aim of this study is to report the efficacy of long subcutaneous tunnelling of external ventricular drains in reducing rates of infection and catheter displacement in a paediatric population. METHODS: In children requiring external ventricular drainage, a long-tunnelled drain was placed and managed according to a locally agreed guideline. End points were novel CSF infection incurred during the time of drainage and re-operation to re-site displaced catheters. Data were compared to other published series. RESULTS: One hundred eighty-one long-tunnelled external ventricular drains (LTEVDs) were inserted. The mean age was 6.6 years (range 0-15.5 years). Reasons for insertion included intraventricular haemorrhage (47 %), infection (27 %), tumour-related hydrocephalus (7.2 %), as a temporising measure (17 %) and trauma (2.2 %). The overall new infection rate for LTEVD was 2.76 %. If the 48 cases where LTEVDs were inserted to treat an existing infection are excluded, the infection rate was 3.8 % (5/133). The mean duration of insertion was 10 days (range 0-42 days). Four LTEVDs (2.2 %) were inadvertently dislodged, requiring reinsertion. Thirteen patients required removal of EVD alone. There was a significant difference (p < 0.05) when comparing our infection rate to 14 publications of infection rates in short-tunnelled EVDs; however, there was no difference when comparing our data to three publications using LTEVDs. CONCLUSION: The use of an antibiotic-impregnated LTEVD, managed according to a predefined guideline, is associated with significantly reduced infection and displacement rates when compared with contemporary series. It is suggested that this reduction is of both clinical and economic benefits.

The important role of sink location in handwashing compliance and microbial sink contamination.

Handwashing is one of the most important means of reducing the spread of infection. In this study, we investigated how sink location and visibility influences handwashing and microbial contamination detected on clinical sinks in 3 pediatric intensive care units. We conclude that the visibility of sinks directly impacts on handwashing frequency and duration and also impacts on levels of bacterial contamination on and around the sink area.

The British antibiotic and silver-impregnated catheters for ventriculoperitoneal shunts multi-centre randomised controlled trial (the BASICS trial): study protocol.

BACKGROUND: Insertion of a ventriculoperitoneal shunt (VPS) for the treatment of hydrocephalus is one of the most common neurosurgical procedures in the UK, but failures caused by infection occur in approximately 8% of primary cases. VPS infection is associated with considerable morbidity and mortality and its management results in substantial cost to the health service. Antibiotic-impregnated (rifampicin and clindamycin) and silver-impregnated VPS have been developed to reduce infection rates. Whilst there is some evidence showing that such devices may lead to a reduction in VPS infection, there are no randomised controlled trials (RCTs) to support their routine use. METHODS/DESIGN: Overall, 1,200 patients will be recruited from 17 regional neurosurgical units in the UK and Ireland. Patients of any age undergoing insertion of their first VPS are eligible. Patients with previous indwelling VPS, active and on-going cerebrospinal fluid (CSF) or peritoneal infection, multiloculated hydrocephalus requiring multiple VPS or neuroendoscopy, and ventriculoatrial or ventriculopleural shunt planned will be excluded. Patients will be randomised 1:1:1 to either standard silicone (comparator), antibiotic-impregnated, or silver-impregnated VPS. The primary outcome measure is time to VPS infection. Secondary outcome measures include time to VPS failure of any cause, reason for VPS failure (infection, mechanical failure, or patient failure), types of bacterial VPS infection (organism type and antibiotic resistance), and incremental cost per VPS failure averted. DISCUSSION: The British antibiotic and silver-impregnated catheters for ventriculoperitoneal shunts multi-centre randomised controlled trial (the BASICS trial) is the first multi-centre RCT designed to determine whether antibiotic or silver-impregnated VPS reduce early shunt infection compared to standard silicone VPS. The results of this study will be used to inform current neurosurgical practice and may potentially benefit patients undergoing shunt surgery in the future. TRIAL REGISTRATION: International Standard Randomised Controlled Trial Number: ISRCTN49474281.

Effect of introduction of antibiotic-impregnated shunt catheters on cerebrospinal fluid shunt infection in children: a large single-center retrospective study.

OBJECT: Infection after both primary and revision shunt surgeries remains a major problem in pediatric neurosurgical practice. Antibiotic-impregnated shunt (AIS) tubing has been proposed to reduce infection rates. The authors report their experience with AIS catheters in their large pediatric neurosurgery department. METHODS: The authors conducted a retrospective case review of consecutive shunt operations performed before (1993-2003) and after (2005-2009) introduction of AIS tubing, with analysis of shunt infection rates and causative organisms identified. RESULTS: The historical control group consisted of 1592 consecutive shunt operations (657 primary insertions), and the AIS study group consisted of 500 consecutive shunt operations (184 primary insertions). Patients ranged in age from 0-17 years. In the historical group, 135 infections were identified (8.4%). In the AIS study group, 25 infections were identified (5%), representing a significant reduction (p < 0.005). The latency to diagnosis of infection was 23 days in the historical group and 139 days in the AIS study group. The infection rates in infants 0-6 months of age were 12.2% (historical group) and 6.7% (AIS group, p < 0.005), and in infants 7-12 months of age the rates were 7.9% (historical group) and 2.7% (AIS group, p < 0.005). In the historical control group, the frequency rank order of causative organisms was coagulase-negative staphylococcus (51.9%), Staphylococcus aureus (31.6%), streptococcus or enterococcus spp. (8.8%), gram-negative organisms (4.4%), and Propionibacterium acnes (2.2%). Organisms responsible for infections in AIS were S. aureus (40%), followed by streptococcus or enterococcus spp. (20%), P. acnes and coagulase-negative staphylococcus (both 16%), and gram-negative organisms (4%). No unusually antibiotic-resistant bacteria were identified in either group. The authors further subdivided the AIS group into those undergoing primary AIS insertion (Subgroup 1), those undergoing revision of non-AIS systems using AIS components (Subgroup 2), and those undergoing revision of AIS systems using AIS components (Subgroup 3). Infection rates were 1.6% in Subgroup 1, 2.5% in Subgroup 2, and 11.7% in Subgroup 3. Staphylococcus aureus was the most common organism identified in infections of the Subgroups 2 and 3. CONCLUSIONS: Use of AIS tubing significantly improves shunt infection rates in both general pediatric and infant populations with no evidence of increased antibiotic resistance, which is in agreement with previous studies. However, the increased infection rate in revision surgery in children with AIS catheters in situ raises questions about their long-term application.

Healthcare environments and spatial variability of healthcare associated infection risk: cross-sectional surveys.

Prevalence of healthcare associated infections remains high in patients in intensive care units (ICU), estimated at 23.4% in 2011. It is important to reduce the overall risk while minimizing the cost and disruption to service provision by targeted infection control interventions. The aim of this study was to develop a monitoring tool to analyze the spatial variability of bacteriological contamination within the healthcare environment to assist in the planning of interventions. Within three cross-sectional surveys, in two ICU wards, air and surface samples from different heights and locations were analyzed. Surface sampling was carried out with tryptic Soy Agar contact plates and Total Viable Counts (TVC) were calculated at 48 hrs (incubation at 37 °C). TVCs were analyzed using Poisson Generalized Additive Mixed Model for surface type analysis, and for spatial analysis. Through three cross-sectional survey, 370 samples were collected. Contamination varied from place-to-place, height-to-height, and by surface type. Hard-to-reach surfaces, such as bed wheels and floor area under beds, were generally more contaminated, but the height level at which maximal TVCs were found changed between cross-sectional surveys. Bedside locations and bed occupation were risk factors for contamination. Air sampling identified clusters of contamination around the nursing station and surface sampling identified contamination clusters at numerous bed locations. By investigating dynamic hospital wards, the methodology employed in this study will be useful to monitor contamination variability within the healthcare environment and should help to assist in the planning of interventions.

Next-generation whole genome sequencing identifies the direction of norovirus transmission in linked patients.

BACKGROUND: Noroviruses are a highly transmissible and major cause of nosocomial gastroenteritis resulting in bed and hospital-ward closures. Where hospital outbreaks are suspected, it is important to determine the routes of spread so that appropriate infection-control procedures can be implemented. To investigate a cluster of norovirus cases occurring in children undergoing bone marrow transplant, we undertook norovirus genome sequencing by next-generation methods. Detailed comparison of sequence data from 2 linked cases enabled us to identify the likely direction of spread. METHODS: Norovirus complementary DNA was amplified by overlapping polymerase chain reaction (PCR) from 13 stool samples from 5 diagnostic real-time PCR-positive patients. The amplicons were sequenced by Roche 454, the genomes assembled by de novo assembly, and the data analyzed phylogenetically. RESULTS: Phylogenetic analysis indicated that patients were infected by viruses similar to 4 distinct GII.4 subtypes and 2 patients were linked by the same virus. Of the 14 sites at which there were differences between the consensus sequences of the 2 linked viral genomes, 9 had minor variants present within one or the other patient. Further analysis confirmed that minor variants at all 9 sites in patient B w ere present as the consensus sequence in patient A. CONCLUSIONS: Phylogenetic analysis excluded a common source of infection in this apparent outbreak. Two of 3 patients on the same ward had closely related viruses, raising the possibility of cross-infection despite protective isolation. Analysis of deep sequencing data enabled us to establish the likely direction of nosocomial transmission.