Multidrug-Resistant Escherichia coli Remains Susceptible to Metal Ions and Graphene-Based Compounds.

Escherichia coli is listed as a priority 1 pathogen on the World Health Organization (WHO) priority pathogen list. For this list of pathogens, new antibiotics are urgently needed to control the emergence and spread of multidrug-resistant strains. This study assessed eighteen metal ions, graphene, and graphene oxide for their antimicrobial efficacy against E. coli in both planktonic and biofilm growth states and the potential synergy between metal ions and graphene-based compounds. Molybdenum and tin ions exhibited the greatest antimicrobial activity against the planktonic states of the isolates with minimal inhibitory concentrations (MIC) ranging between 13 mg/L and 15.6 mg/L. Graphene oxide had no antimicrobial effect against any of the isolates, while graphene showed a moderate effect against E. coli (MIC, 62.5 mg/L). Combinations of metal ions and graphene-based compounds including tin-graphene, tin-graphene oxide, gold-graphene, platinum-graphene, and platinum-graphene oxide exhibited a synergistic antimicrobial effect (FIC ≤ 0.5), inhibiting the planktonic and biofilm formation of the isolates regardless of their antibiotic-resistant profiles. The bactericidal effect of the metal ions and the synergistic effects when combined with graphene/graphene oxide against medically relevant pathogens demonstrated that the antimicrobial efficacy was increased. Hence, such agents may potentially be used in the production of novel antimicrobial/antiseptic agents.

Malignant rhabdoid tumor of the orbit in an infant.

We present the case of an infant with rapidly progressing orbital tumor that had initial radiological and clinical features of both rhabdomyosarcoma and capillary hemangioma. The patient was eventually diagnosed with malignant rhabdoid tumor of the orbit. We discuss the salient histological and radiological features of our case and review the literature on orbital malignant rhabdoid tumors.

Validated respiratory drug deposition predictions from 2D and 3D medical images with statistical shape models and convolutional neural networks.

For the one billion sufferers of respiratory disease, managing their disease with inhalers crucially influences their quality of life. Generic treatment plans could be improved with the aid of computational models that account for patient-specific features such as breathing pattern, lung pathology and morphology. Therefore, we aim to develop and validate an automated computational framework for patient-specific deposition modelling. To that end, an image processing approach is proposed that could produce 3D patient respiratory geometries from 2D chest X-rays and 3D CT images. We evaluated the airway and lung morphology produced by our image processing framework, and assessed deposition compared to in vivo data. The 2D-to-3D image processing reproduces airway diameter to 9% median error compared to ground truth segmentations, but is sensitive to outliers of up to 33% due to lung outline noise. Predicted regional deposition gave 5% median error compared to in vivo measurements. The proposed framework is capable of providing patient-specific deposition measurements for varying treatments, to determine which treatment would best satisfy the needs imposed by each patient (such as disease and lung/airway morphology). Integration of patient-specific modelling into clinical practice as an additional decision-making tool could optimise treatment plans and lower the burden of respiratory diseases.

Epidemiology, Clinical Features, and Antimicrobial Resistance of Invasive Escherichia Coli Disease in Patients Admitted in Tertiary Care Hospitals.

Background: Invasive Escherichia coli disease (IED), including bloodstream infection, sepsis, and septic shock, can lead to high hospitalization and mortality rates. This multinational study describes the clinical profile of patients with IED in tertiary care hospitals. Methods: We applied clinical criteria of systemic inflammatory response syndrome (SIRS), sepsis, or septic shock to patients hospitalized with culture-confirmed E coli from urine or a presumed sterile site. We assessed a proposed clinical case definition against physician diagnoses. Results: Most patients with IED (N = 902) were adults aged ≥60 years (76.5%); 51.9%, 25.1%, and 23.0% of cases were community-acquired (CA), hospital-acquired (HA), and healthcare-associated (HCA), respectively. The urinary tract was the most common source of infection (52.3%). Systemic inflammatory response syndrome, sepsis, and septic shock were identified in 77.4%, 65.3%, and 14.1% of patients, respectively. Patients >60 years were more likely to exhibit organ dysfunction than those ≤60 years; this trend was not observed for SIRS. The case-fatality rate (CFR) was 20.0% (60-75 years, 21.5%; ≥75 years, 22.2%), with an increase across IED acquisition settings (HA, 28.3%; HCA, 21.7%; CA, 15.2%). Noticeably, 77.8% of patients initiated antibiotic use on the day of culture sample collection. A total of 65.6% and 40.8% of E coli isolates were resistant to ≥1 agent in ≥1 or ≥2 drug class(es). A 96.1% agreement was seen between the proposed clinical case definition and physician's diagnoses of IED. Conclusions: This study contributes valuable, real-world data about IED severity. An accepted case definition could promote timely and accurate diagnosis of IED and inform the development of novel preventative strategies.

Clinical and microbiological investigation into mixed growth urine cultures.

Introduction. Urine samples submitted for investigation of urinary tract infection (UTI) may identify more than one bacterial isolate. These samples may be reported as 'mixed growth urine culture' (MGUC). The clinical significance of MGUC remains controversial.Hypothesis/Gap Statement. The impact of MGUC on patient management is not known and should be assessed. To describe MGUC and assess its impact on patient management.Methodology. Microbiology laboratory reports (Leeds, UK) were retrospectively analysed and urine cultures reported as MGUC from a 1 week period underwent detailed laboratory analysis. Semi-structured interviews of NHS clinicians' response to MGUC reports were explored for emergent themes.Results. In 2018, 12.4 % (14,323/115,664) of urine specimens processed to detect bacterial pathogens were reported as MGUC. Among a total of 200 MGUC samples identified within 1 week in 2019, detailed laboratory analysis identified 459 bacterial isolates. Enterococcus species (30.1 %) and Escherichia coli (27.5 %) were the most frequently isolated and the most frequent organism combination (24 %). In total, 65.5 % cultures contained two organisms and 82.5 % of all MGUC contained at least one Enterobacterales. Interviews found clinicians believed MGUC reports represented detection of many commensal bacteria. Clinicians indicated they were more likely to diagnose and treat a UTI when provided with urine culture reports derived from detailed microbial analysis of MGUC, including identity and antibiotic sensitivity of organisms.Conclusions. This study highlights the potential underuse of information derived from microbiological analysis of urine samples. Interpretive commentary on reports together with education for interpretation of enhanced reports should be explored further to improve outcomes in patients with UTI.

The CABI Trial: an Unblinded Parallel Group Randomised Controlled Feasibility Trial of Long-Course Antibiotic Therapy (28 Days) Compared with Short Course (≤ 10 Days) in the Prevention of Relapse in Adults Treated for Complicated Intra-Abdominal Infection.

PURPOSE: Relapse after complicated intra-abdominal infection (cIAI) remains common after treatment. The optimal antibiotic treatment duration for cIAIs is uncertain, especially in cases where source control is not achieved. We hypothesised that in patients with cIAIs, regardless of source control intervention, there would be a lower relapse rate with long-course antibiotics (28 days) compared with short course (≤ 10 days). We piloted a trial comparing ≤ 10-day with 28-day antibiotic treatment for cIAI. METHODS: A randomised controlled unblinded feasibility trial was conducted. Eligible participants were adult patients with a cIAI that were diagnosed ≤ 6 days prior to screening. Randomisation was to long-course (28 days) or short-course (≤10 days) antibiotic therapy. Choice of antibiotics was determined by the clinical team. Participants were followed up for 90 days. Primary outcomes were willingness of participants to be randomised and feasibility of trial procedures. RESULTS: In total, 172 patients were screened, 84/172 (48.8%) were eligible, and 31/84 (36.9%) were randomised. Patients were assigned to either the short-course arm (18/31, 58.0%) or the long-course arm (13/31, 41.9%). One patient in the short-course arm withdrew after randomisation. In the short-course arm, 4/17 (23.5%) were treated for a cIAI relapse vs 0/13 (0.0%) relapses in the long-course arm. Protocol violations included deviations from protocol-assigned antibiotic duration and interruptions to antibiotic therapy. CONCLUSIONS: This feasibility study identified opportunities to increase recruitment in a full trial. This study demonstrates completion of a randomised controlled trial to further evaluate if the optimum antibiotic duration for cIAIs is feasible. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03265834.

Metal ions and graphene-based compounds as alternative treatment options for burn wounds infected by antibiotic-resistant Pseudomonas aeruginosa.

Burn infections caused by Pseudomonas aeruginosa pose a major complication in wound healing. This study aimed to determine the antimicrobial effect of metal ions, graphene (Gr), and graphene oxide (GO), individually and in combination, against the planktonic and biofilm states of two antimicrobially resistant clinical strains of P. aeruginosa each with different antibiotic resistance profiles. Minimum inhibitory, minimum bactericidal, and fractional inhibitory concentrations were performed to determine the efficacy of the metal ions and graphene composites individually and their synergy in combination. Crystal violet biofilm and XTT assays measured the biofilm inhibition and metabolic activity, respectively. Molybdenum, platinum, tin, gold, and palladium ions exhibited the greatest antimicrobial activity (MIC = 7.8-26.0 mg/L), whilst GO and Gr demonstrated moderate-to-no effect against the planktonic bacterial cells, irrespective of their antibiograms. Biofilms were inhibited by zinc, palladium, silver, and graphene. In combination, silver-graphene and molybdenum-graphene inhibited both the planktonic and biofilm forms of the bacteria making them potential candidates for development into topical antimicrobials for burns patients infected with antibiotic-resistant P. aeruginosa.

Consensus-based antimicrobial resistance and stewardship competencies for UK undergraduate medical students.

BACKGROUND: In the UK there is limited coverage of antimicrobial stewardship across postgraduate curricula and evidence that final year medical students have insufficient and inconsistent antimicrobial stewardship teaching. A national undergraduate curriculum for antimicrobial resistance and stewardship is required to standardize an adequate level of understanding for all future doctors. OBJECTIVES: To provide a UK national consensus on competencies for antimicrobial resistance and stewardship for undergraduate medical education. METHODS: Using the modified Delphi method over two online survey rounds, an expert panel comprising leads for infection teaching from 25 UK medical schools reviewed competency descriptors for antimicrobial resistance and stewardship education. RESULTS: There was a response rate of 100% with all 28 experts who agreed to take part completing both survey rounds. Following the first-round survey, of the initial 55 descriptors, 43 reached consensus (78%). The second-round survey included the 12 descriptors from the first round in which agreement had not been reached, four amended descriptors and 12 new descriptors following qualitative feedback from the panel members. Following the second-round survey, a total of 58 consensus-based competency descriptors within six overarching domains were identified. CONCLUSIONS: The consensus-based competency descriptors defined here can be used to inform standards, design curricula, develop assessment tools and direct UK undergraduate medical education.

Measuring outcomes in complicated intra-abdominal infections.

PURPOSE OF REVIEW: Complicated intra-abdominal infections (cIAIs) are associated with significant morbidity and mortality. Clinical trials should help guide and improve the management of cIAIs. However, inappropriate selection or measurement of outcomes in cIAIs clinical trials can lead to misleading results on the effectiveness of interventions. This review aims to describe how outcomes are reported in randomized controlled trials evaluating antibiotic treatment for cIAIs and discuss how outcome reporting may be improved. RECENT FINDINGS: Commonly used primary outcomes are treatment success or failure, and these outcomes are endorsed by regulatory bodies. However, a consensus objective definition of either is not available and current measures are prone to bias. Variation exists in timing of outcome evaluation and analysis populations, which can lead to further bias. Use of core outcome sets can help standardize outcome reporting. SUMMARY: Inconsistency in outcome selection and reporting can lead to misleading results and impedes meta-analysis of data. Further progress, engaging clinical trialists, regulatory authorities, clinicians and patients is required to achieve consensus on which outcomes should be reported and how and when to measure them.

Management of cervical spine trauma in children.

PURPOSE: Paediatric cervical spine injuries are fortunately a rare entity. However, they do have the potential for devastating neurological sequelae with lifelong impact on the patient and their family. Thus, management ought to be exceptional from the initial evaluation at the scene of the injury, through to definitive management and rehabilitation. METHODS: We set out to review cervical spine injuries in children and advise on current best practice with regards to management. RESULTS: Epidemiology, initial management at the scene of injury, radiological findings and pitfalls of cervical spine trauma are outlined. Strategies for conservative and surgical management are detailed depending on the pattern of injury. The management of spinal cord injuries without radiological abnormality (SCIWORA) and cranio-cervical arterial injuries is also reviewed. CONCLUSIONS: Due to a paucity of evidence in these rare conditions, expert opinion is necessary to guide best practice management and to ensure the best chance of a good outcome for the injured child.

Colo-Pro: a pilot randomised controlled trial to compare standard bolus-dosed cefuroxime prophylaxis to bolus-continuous infusion-dosed cefuroxime prophylaxis for the prevention of infections after colorectal surgery.

Standard bolus-dosed antibiotic prophylaxis may not inhibit growth of antibiotic resistant colonic bacteria, a cause of SSIs after colorectal surgery. An alternative strategy is continuous administration of antibiotic throughout surgery, maintaining concentrations of antibiotics that inhibit growth of resistant bacteria. This study is a pilot comparing bolus-continuous infusion with bolus-dosed cefuroxime prophylaxis in colorectal surgery. This is a pilot randomised controlled trial in which participants received cefuroxime bolus-infusion (intervention arm) targeting free serum cefuroxime concentrations of 64 mg/L, or 1.5 g cefuroxime as a bolus dose four-hourly (standard arm). Patients in both arms received metronidazole (500 mg intravenously). Eligible participants were adults undergoing colorectal surgery expected to last for over 2 h. Results were analysed on an intention-to-treat basis. The study was successfully piloted, with 46% (90/196) of eligible patients recruited and 89% (80/90) of participants completing all components of the protocol. A trialled bolus-continuous dosing regimen was successful in maintaining free serum cefuroxime concentrations of 64 mg/L. No serious adverse reactions were identified. Rates of SSIs (superficial and deep SSIs) were lower in the intervention arm than the standard treatment arm (24% (10/42) vs. 30% (13/43)), as were infection within 30 days of operation (41% (17/43) vs 51% (22/43)) and urinary tract infections (2% (1/42) vs. 9% (4/43)). These infection rates can be used to power future clinical trials. This study demonstrates the feasibility of cefuroxime bolus-continuous infusion of antibiotic prophylaxis trials, and provides safety data for infusions targeting free serum cefuroxime concentrations of 64 mg/L. Trial registration: NCT02445859 .

A systematic review of randomised clinical trials for oral antibiotic treatment of acute pyelonephritis.

There is increasing resistance to the oral antibiotics currently recommended for the treatment of pyelonephritis, and increased healthcare costs are associated with the reliance on alternative intravenous agents. We, therefore, performed a systematic review of randomised controlled trials to determine the clinical efficacy and safety of oral antibiotics for the treatment of pyelonephritis in adults. A search of four major medical databases (MEDLINE, Embase+ Embase classic, CENTRAL and Cochrane Database for Systematic Reviews) in addition to manual reference searching of relevant reviews was conducted. Clinical cure and adverse event rates were reported, and trial quality and bias were assessed. A total of 277 studies were reviewed; five studies matched all eligibility criteria and were included. Antibiotics included were cefaclor, ciprofloxacin, gatifloxacin, levofloxacin, lomefloxacin, loracarbef, norfloxacin, rufloxacin and trimethoprim-sulfamethoxazole. In included studies, the clinical success of the outpatient treatment of pyelonephritis by cefaclor, ciprofloxacin and norfloxacin at 4 to 6 weeks was comparable at between 83 to 95%. Relatively high rates of adverse events were noted in a trial of ciprofloxacin (24%) and trimethoprim-sulfamethoxazole (33%). Significant heterogeneity between all aspects of the trial designs was identified, with all studies having a potential for bias. This review demonstrates a need for high-quality clinical trials into the oral antibiotic treatment of pyelonephritis, with more consistent designs and reporting of outcomes. There are data to support further research into oral norfloxacin and cefaclor for the outpatient treatment of pyelonephritis in adults.

Corrigendum: Landscape of X chromosome inactivation across human tissues.

This corrects the article DOI: 10.1038/nature24265.

Landscape of X chromosome inactivation across human tissues.

X chromosome inactivation (XCI) silences transcription from one of the two X chromosomes in female mammalian cells to balance expression dosage between XX females and XY males. XCI is, however, incomplete in humans: up to one-third of X-chromosomal genes are expressed from both the active and inactive X chromosomes (Xa and Xi, respectively) in female cells, with the degree of 'escape' from inactivation varying between genes and individuals. The extent to which XCI is shared between cells and tissues remains poorly characterized, as does the degree to which incomplete XCI manifests as detectable sex differences in gene expression and phenotypic traits. Here we describe a systematic survey of XCI, integrating over 5,500 transcriptomes from 449 individuals spanning 29 tissues from GTEx (v6p release) and 940 single-cell transcriptomes, combined with genomic sequence data. We show that XCI at 683 X-chromosomal genes is generally uniform across human tissues, but identify examples of heterogeneity between tissues, individuals and cells. We show that incomplete XCI affects at least 23% of X-chromosomal genes, identify seven genes that escape XCI with support from multiple lines of evidence and demonstrate that escape from XCI results in sex biases in gene expression, establishing incomplete XCI as a mechanism that is likely to introduce phenotypic diversity. Overall, this updated catalogue of XCI across human tissues helps to increase our understanding of the extent and impact of the incompleteness in the maintenance of XCI.

Covert dissemination of carbapenemase-producing Klebsiella pneumoniae (KPC) in a successfully controlled outbreak: long- and short-read whole-genome sequencing demonstrate multiple genetic modes of transmission.

BACKGROUND: Carbapenemase-producing Enterobacteriaceae (CPE), including KPC-producing Klebsiella pneumoniae (KPC-Kpn), are an increasing threat to patient safety. OBJECTIVES: To use WGS to investigate the extent and complexity of carbapenemase gene dissemination in a controlled KPC outbreak. MATERIALS AND METHODS: Enterobacteriaceae with reduced ertapenem susceptibility recovered from rectal screening swabs/clinical samples, during a 3 month KPC outbreak (2013-14), were investigated for carbapenemase production, antimicrobial susceptibility, variable-number-tandem-repeat profile and WGS [short-read (Illumina), long-read (MinION)]. Short-read sequences were used for MLST and plasmid/Tn4401 fingerprinting, and long-read sequence assemblies for plasmid identification. Phylogenetic analysis used IQTree followed by ClonalFrameML, and outbreak transmission dynamics were inferred using SCOTTI. RESULTS: Twenty patients harboured KPC-positive isolates (6 infected, 14 colonized), and 23 distinct KPC-producing Enterobacteriaceae were identified. Four distinct KPC plasmids were characterized but of 20 KPC-Kpn (from six STs), 17 isolates shared a single pKpQIL-D2 KPC plasmid. All isolates had an identical transposon (Tn4401a), except one KPC-Kpn (ST661) with a single nucleotide variant. A sporadic case of KPC-Kpn (ST491) with Tn4401a-carrying pKpQIL-D2 plasmid was identified 10 months before the outbreak. This plasmid was later seen in two other species and other KPC-Kpn (ST14,ST661) including clonal spread of KPC-Kpn (ST661) from a symptomatic case to nine ward contacts. CONCLUSIONS: WGS of outbreak KPC isolates demonstrated blaKPC dissemination via horizontal transposition (Tn4401a), plasmid spread (pKpQIL-D2) and clonal spread (K. pneumoniae ST661). Despite rapid outbreak control, considerable dissemination of blaKPC still occurred among K. pneumoniae and other Enterobacteriaceae, emphasizing its high transmission potential and the need for enhanced control efforts.

Structural changes in cell wall pectins during strawberry fruit development.

Strawberry (Fragaria × anannasa Duch.) is one of the most important soft fruit. Rapid loss of firmness occurs during the ripening process, resulting in a short shelf life and high economic losses. To get insight into the role of pectin matrix in the softening process, cell walls from strawberry fruit at two developmental stages, unripe-green and ripe-red, were extracted and sequentially fractionated with different solvents to obtain fractions enriched in a specific component. The yield of cell wall material as well as the per fresh weight contents of the different fractions decreased in ripe fruit. The largest reduction was observed in the pectic fractions extracted with a chelating agent (trans-1,2- diaminocyclohexane-N,N,N'N'-tetraacetic acid, CDTA fraction) and those covalently bound to the wall (extracted with Na2CO3). Uronic acid content of these two fractions also decreased significantly during ripening, but the amount of soluble pectins extracted with phenol:acetic acid:water (PAW) and water increased in ripe fruit. Fourier transform infrared spectroscopy of the different fractions showed that the degree of esterification decreased in CDTA pectins but increased in soluble fractions at ripen stage. The chromatographic analysis of pectin fractions by gel filtration revealed that CDTA, water and, mainly PAW polyuronides were depolymerised in ripe fruit. By contrast, the size of Na2CO3 pectins was not modified. The nanostructural characteristics of CDTA and Na2CO3 pectins were analysed by atomic force microscopy (AFM). Isolated pectic chains present in the CDTA fractions were significantly longer and more branched in samples from green fruit than those from red fruit. No differences in contour length were observed in Na2CO3 strands between samples of both stages. However, the percentage of branched chains decreased from 19.7% in unripe samples to 3.4% in ripe fruit. The number of pectin aggregates was higher in green fruit samples of both fractions. These results show that the nanostructural complexity of pectins present in CDTA and Na2CO3 fractions diminishes during fruit development, and this correlates with the solubilisation of pectins and the softening of the fruit.

Paternally Inherited DLK1 Deletion Associated With Familial Central Precocious Puberty.

Context: Central precocious puberty (CPP) results from premature activation of the hypothalamic-pituitary-gonadal axis. Few genetic causes of CPP have been identified, with the most common being mutations in the paternally expressed imprinted gene MKRN3. Objective: To identify the genetic etiology of CPP in a large multigenerational family. Design: Linkage analysis followed by whole-genome sequencing was performed in a family with five female members with nonsyndromic CPP. Detailed phenotyping was performed at the time of initial diagnosis and long-term follow-up, and circulating levels of Delta-like 1 homolog (DLK1) were measured in affected individuals. Expression of DLK1 was measured in mouse hypothalamus and in kisspeptin-secreting neuronal cell lines in vitro. Setting: Endocrine clinic of an academic medical center. Patients: Patients with familial CPP were studied. Results: A complex defect of DLK1 (∼14-kb deletion and 269-bp duplication) was identified in this family. This deletion included the 5' untranslated region and the first exon of DLK1, including the translational start site. Only family members who inherited the defect from their father have precocious puberty, consistent with the known imprinting of DLK1. The patients did not demonstrate additional features of the imprinted disorder Temple syndrome except for increased fat mass. Serum DLK1 levels were undetectable in all affected individuals. Dlk1 was expressed in mouse hypothalamus and in kisspeptin neuron-derived cell lines. Conclusion: We identified a genomic defect in DLK1 associated with isolated familial CPP. MKRN3 and DLK1 are both paternally expressed imprinted genes. These findings suggest a role of genomic imprinting in regulating the timing of human puberty.

Unravelling the nanostructure of strawberry fruit pectins by endo-polygalacturonase digestion and atomic force microscopy.

Pectins analysed by AFM are visualized as individual chains, branched or unbranched, and aggregates. To investigate the nature of these structures, sodium carbonate soluble pectins from strawberry fruits were digested with endo-polygalacturonase M2 from Aspergillus aculeatus and visualized by AFM. A gradual decrease in the length of chains was observed as result of the treatment, reaching a minimum LN value of 22nm. The branches were not visible after 2h of enzymatic incubation. The size of complexes also diminished significantly with the enzymatic digestion. A treatment to hydrolyse rhamnogalacturonan II borate diester bonds neither affected chains length or branching nor complex size but reduced the density of aggregates. These results suggest that chains are formed by a mixture of homogalacturonan and more complex molecules composed by a homogalacturonan unit linked to an endo-PG resistant unit. Homogalacturonan is a structural component of the complexes and rhamnogalacturonan II could be involved in their formation.

Acute norovirus gastroenteritis in children in a highly rotavirus-vaccinated population in Northeast Brazil.

BACKGROUND: Gastroenteritis is one of the most important causes of morbidity and mortality in children and an important etiological agent is norovirus. OBJECTIVE: We describe the occurrence and characteristics of norovirus diarrhoea in children from Sergipe, Northeast-Brazil, over two consecutive periods of three years following rotavirus vaccine introduction. STUDY DESIGN: A cross sectional hospital-based survey conducted from October-2006 to September-2009 and from July-2011 to January-2013. Acute diarrhoea cases had a stool sample collected and tested for norovirus by RT-PCR and positive samples were sequenced. RESULTS: In total 280 (19.6%) of 1432 samples were norovirus positive, including 204 (18.3%) of 1113 samples collected during the first period and 76 (23.9%) of 318 collected during the second period. The proportion of children with norovirus infection increased significantly through the second study period (χ2 for trend=6.7; p=0.009), was more frequent in rotavirus vaccinated and in younger children (p<0.001). Of 280 norovirus-positive specimens, 188 (67.1%) were sequenced. Of these, 12 were genogroup I and 176 genogroup II. The main genotype was GII.4 (149/188, 79.3%), followed by GII.2 (6, 3.2%) and GII.6 (5, 2.6%). CONCLUSION: Norovirus annual detection rates increased over the study period. The detection of norovirus was higher among young children.