Erratum to "Outbreak of New Delhi Metallo-Beta-lactamase Carbapenemase Producing Enterobacterales on a bone marrow transplant unit: Role of the environment" Infect Prev Pract, Vol. 3 (June 2021) Article Number: 100125.

[This corrects the article DOI: 10.1016/j.infpip.2021.100125.].

The E3 ubiquitin ligase HECTD1 contributes to cell proliferation through an effect on mitosis.

The cell cycle is tightly regulated by protein phosphorylation and ubiquitylation events. During mitosis, the multi-subunit cullin-RING E3 ubiquitin ligase APC/c functions as a molecular switch which signals for one cell to divide into two daughter cells, through the ubiquitylation and proteasomal degradation of mitotic cyclins. The contributions of other E3 ligase families during cell cycle progression remain less well understood. Similarly, the roles of ubiquitin chain types beyond homotypic K48 chains in S-phase or branched K11/K48 chains during mitosis, also remain to be fully determined. Our recent findings that HECTD1 ubiquitin ligase activity assembles branched K29/K48 ubiquitin linkages prompted us to evaluate HECTD1 function during the cell cycle. We used transient knockdown and genetic knockout to show that HECTD1 depletion in HEK293T and HeLa cells decreases cell number and we established that this is mediated through loss of ubiquitin ligase activity. Interestingly, we found that HECTD1 depletion increases the proportion of cells with aligned chromosomes (Prometa/Metaphase) and we confirmed this molecularly using phospho-Histone H3 (Ser28) as a marker of mitosis. Time-lapse microscopy of NEBD to anaphase onset established that HECTD1-depleted cells take on average longer to go through mitosis. In line with this data, HECTD1 depletion reduced the activity of the Spindle Assembly Checkpoint, and BUB3, a component of the Mitosis Checkpoint Complex, was identified as novel HECTD1 interactor. BUB3, BUBR1 or MAD2 protein levels remained unchanged in HECTD1-depleted cells. Overall, this study reveals a novel putative role for HECTD1 during mitosis and warrants further work to elucidate the mechanisms involved.

Outbreak of New Delhi Metallo-Beta-lactamase Carbapenemase Producing Enterobacterales on a bone marrow transplant unit: Role of the environment.

BACKGROUND: Carbapenemase Producing Enterobacterales (CPE) are a global health concern. Nosocomial outbreaks have been reported globally with patient-to-patient transmission felt to be the most frequent route of cross-transmission. AIM: To describe the investigation and control of an outbreak of healthcare-associated New Delhi Metallo-beta-lactamase (NDM) CPE on a haematology ward, over 2 months. METHODS: Four patients acquired CPE; all had gastrointestinal tract colonisation with two subsequently developing bacteraemias. The outbreak team performed a retrospective review, prospective case finding and environmental sampling using swabs, settle plates, air and water sampling. Immediate control measures were implemented including appropriate isolation of cases and additional ward cleaning with chlorine disinfectant, ultra-violet light decontamination and hydrogen peroxide. FINDINGS: Following two cases of nosocomial acquired CPE prospective case finding identified two further cases. 4.6% of the initial environmental samples were positive for CPE including from waste water sites, the ward sluice and the ward kitchen. Three of the four CPE isolates were identical on pulse field gel electrophoresis (PFGE) typing. Detection of the CPE from the ward kitchen environmental samples suggests a possible role for cross transmission. CONCLUSION: This is the first CPE outbreak report to highlight the role of a ward kitchen as a possible source of cross-transmission. In view of this we suggest ward kitchens are reviewed and investigated in nosocomial CPE outbreaks.

Utility of the FebriDx point-of-care assay in supporting a triage algorithm for medical admissions with possible COVID-19: an observational cohort study.

OBJECTIVE: To evaluate a triage algorithm used to identify and isolate patients with suspected COVID-19 among medical patients needing admission to hospital using simple clinical criteria and the FebriDx assay. DESIGN: Retrospective observational cohort. SETTING: Large acute National Health Service hospital in London, UK. PARTICIPANTS: All medical admissions from the emergency department between 10 August 2020 and 4 November 2020 with a valid SARS-CoV-2 RT-PCR result. INTERVENTIONS: Medical admissions were triaged as likely, possible or unlikely COVID-19 based on clinical criteria. Patients triaged as possible COVID-19 underwent FebriDx lateral flow assay on capillary blood, and those positive for myxovirus resistance protein A (a host response protein) were managed as likely COVID-19. PRIMARY OUTCOME MEASURES: Diagnostic accuracy (sensitivity, specificity and predictive values) of the algorithm and the FebriDx assay using SARS-CoV-2 RT-PCR from nasopharyngeal swabs as the reference standard. RESULTS: 4.0% (136) of 3443 medical admissions had RT-PCR confirmed COVID-19. Prevalence of COVID-19 was 46% (80/175) in those triaged as likely, 4.1% (50/1225) in possible and 0.3% (6/2033) in unlikely COVID-19. Using a SARS-CoV-2 RT-PCR reference standard, clinical triage had sensitivity of 96% (95% CI 91% to 98%) and specificity of 61.5% (95% CI 59.8% to 63.1%), while the triage algorithm including FebriDx had sensitivity of 93% (95% CI 87% to 96%) and specificity of 86.4% (95% CI 85.2% to 87.5%). While 2033 patients were deemed not to require isolation using clinical criteria alone, the addition of FebriDx to clinical triage allowed a further 826 patients to be released from isolation, reducing the need for isolation rooms by 9.5 per day, 95% CI 8.9 to 10.2. Ten patients missed by the algorithm had mild or asymptomatic COVID-19. CONCLUSIONS: A triage algorithm including the FebriDx assay had good sensitivity and was useful to 'rule-out' COVID-19 among medical admissions to hospital.

The deubiquitinase TRABID stabilizes the K29/K48-specific E3 ubiquitin ligase HECTD1.

Ubiquitin is a versatile posttranslational modification, which is covalently attached to protein targets either as a single moiety or as a ubiquitin chain. In contrast to K48 and K63-linked chains, which have been extensively studied, the regulation and function of most atypical ubiquitin chains are only starting to emerge. The deubiquitinase TRABID/ZRANB1 is tuned for the recognition and cleavage of K29 and K33-linked chains. Yet, substrates of TRABID and the cellular functions of these atypical ubiquitin signals remain unclear. We determined the interactome of two TRABID constructs rendered catalytic dead either through a point mutation in the catalytic cysteine residue or through removal of the OTU catalytic domain. We identified 50 proteins trapped by both constructs and which therefore represent candidate substrates of TRABID. The E3 ubiquitin ligase HECTD1 was then validated as a substrate of TRABID and used UbiCREST and Ub-AQUA proteomics to show that HECTD1 preferentially assembles K29- and K48-linked ubiquitin chains. Further in vitro autoubiquitination assays using ubiquitin mutants established that while HECTD1 can assemble short homotypic K29 and K48-linked chains, it requires branching at K29/K48 in order to achieve its full ubiquitin ligase activity. We next used transient knockdown and genetic knockout of TRABID in mammalian cells in order to determine the functional relationship between TRABID and HECTD1. This revealed that upon TRABID depletion, HECTD1 is readily degraded. Thus, this study identifies HECTD1 as a mammalian E3 ligase that assembles branched K29/K48 chains and also establishes TRABID-HECTD1 as a DUB/E3 pair regulating K29 linkages.

Improving children's and their visitors' hand hygiene compliance.

BACKGROUND: Numerous interventions have tried to improve healthcare workers' hand hygiene compliance. However, little attention has been paid to children's and their visitors' compliance. AIM: To test whether interactive educational interventions increase children's and visitors' compliance with hand hygiene. METHODS: This was a cluster randomised study of hand hygiene compliance before and after the introduction of educational interventions. Observations were compared for different moments of hygiene and times of the day. Qualitative data in the form of questionnaire-based structured interviews were obtained. FINDINGS: Hand hygiene compliance increased by 24.4% (P < 0.001) following the educational interventions, with children's compliance reaching 40.8% and visitors' being 50.8%. Compliance varied depending on which of the five moments of hygiene was observed (P < 0.001), with the highest compliance being 'after body fluid exposure' (72.7%). Responses from questionnaires showed educational interventions raised awareness of the importance of hand hygiene (69%, 57%) compared to those who had not experienced the educational intervention (50%). CONCLUSION: Educational interventions may result in a significant increase in children's and visitors' hand hygiene (P < 0.001).

An observational study of hand hygiene adherence following the introduction of an education intervention.

Hand hygiene adherence needs to be increased and sustained in order to prevent and reduce healthcare associated infections. We implemented an educational intervention and observed the adherence of healthcare workers, patients and visitors over 24 hour periods at four observation points. For healthcare workers a total of 2,294 opportunities were observed and for patients and visitors, a total of 597 opportunities were observed. Healthcare worker adherence increased following the introduction of the educational intervention, with 53.0% (282/532) adherence at baseline (observation point 1), and was sustained varying between 67.7% and 70.8% in the post-intervention points (p=0.0007). The greatest increase in adherence was observed between baseline and the observation point 2. Adherence varied according to type of opportunity (p<0.0001) with the lowest level of adherence observed after contact with patient surroundings, however there was no obvious trend across the observation points. There was an interaction between point of study and ward (p=0.0001). For patients and visitors, adherence did differ according to the point of study (p=0.0074) with adherence prior to the intervention being 49.1% and then ranging from 43.5-61.8%. We suggest that future educational interventions should be implemented as this study implies that there is potential for increased and sustained adherence to hand hygiene protocols.

An observational study of hand hygiene compliance in paediatric wards.

AIMS AND OBJECTIVES: To measure healthcare workers', children's and visitors' hand hygiene compliance in a paediatric oncology ward and a paediatric respiratory ward in an English hospital. BACKGROUND: Children are especially vulnerable to healthcare-associated infections, yet few studies have reported on hand hygiene compliance in paediatric clinical areas. DESIGN: This was an observational study. METHOD: We measured hand hygiene compliance over an eight-hour period in two hospital wards using the 'five moments of hand hygiene' observation tool. We monitored a total of 407 hand hygiene opportunities. RESULTS: Overall opportunities for compliance were 74% for healthcare workers (n = 315) and children and visitors 23% (n = 92). Compliance was 84% for allied health professionals, 81% for doctors, 75% for nurses and 73% for ancillary and other staff. Hand hygiene compliance varied depending on which of the five moments of hygiene healthcare workers were undertaking (p < 0·001), with compliance before child contact 90% (140/155); after child contact 78% (89/114); after body fluid exposure 75% (3/4); and after surroundings contact 36% (15/42). For healthcare workers and visitors, there was no evidence of an association between time of day and their hand hygiene compliance, and for visitors to the oncology ward, hand hygiene compliance was higher (p < 0·05). CONCLUSION: Owing to the nature of the clinical environments, we are unable to draw conclusions about children's hand hygiene compliance; however, visitors' compliance was low. Among healthcare workers, levels of compliance were higher compared with previous reported estimates. RELEVANCE TO CLINICAL PRACTICE: Visitors had the lowest level of compliance yet owing to the nature of the clinical environments, nearly a quarter of care is delivered by them rather than healthcare workers, and so, this offers opportunities for specific future interventions aimed at families and carers.

The potential of pulsed low intensity ultrasound to stimulate chondrocytes matrix synthesis in agarose and monolayer cultures.

Pulsed low intensity ultrasound (PLIUS) has been used successfully for bone fracture repair and has therefore been suggested for cartilage regeneration. However, previous in vitro studies with chondrocytes show conflicting results as to the effect of PLIUS on the elaboration of extracellular matrix. This study tests the hypothesis that PLIUS, applied for 20 min/day, stimulates the synthesis of sulphated glycosaminoglycan (sGAG) by adult bovine articular chondrocytes cultured in either monolayer or agarose constructs. For both culture models, PLIUS at either 30 or 100 mW/cm(2) intensity had no net effect on the total sGAG content. Although PLIUS at 100 mW/cm(2) did induce a 20% increase in sGAG content at day 2 of culture in agarose, this response was lost by day 5. Intensities of 200 and 300 mW/cm(2) resulted in cell death probably due to heating from the ultrasound transducers. The lack of a sustained up-regulation of sGAG synthesis may reflect the suggestion that PLIUS only induces a stimulatory effect in the presence of a tissue injury response. These results suggest that PLIUS has a limited potential to provide an effective method of stimulating matrix production as part of a tissue engineering strategy for cartilage repair.

How knowledgeable are nurses about C. difficile?

Jacqueline Randle and colleagues report the results of their small-scale study of infection control link professionals' knowledge about Clostridium difficile and how they use this knowledge in practice.