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Shiga toxin-producing Escherichia coli (STEC) infection can cause serious illness including haemolytic uraemic syndrome. The role of socio-economic status (SES) in differential clinical presentation and exposure to potential risk factors amongst STEC cases has not previously been reported in England. We conducted an observational study using a dataset of all STEC cases identified in England, 2010–2015. Odds ratios for clinical characteristics of cases and foodborne, waterborne and environmental risk factors were estimated using logistic regression, stratified by SES, adjusting for baseline demographic factors. Incidence was higher in the highest SES group compared to the lowest (RR 1.54, 95% CI 1.19–2.00). Odds of Accident and Emergency attendance (OR 1.35, 95% CI 1.10–1.75) and hospitalisation (OR 1.71, 95% CI 1.36–2.15) because of illness were higher in the most disadvantaged compared to the least, suggesting potential lower ascertainment of milder cases or delayed care-seeking behaviour in disadvantaged groups. Advantaged individuals were significantly more likely to report salad/fruit/vegetable/herb consumption (OR 1.59, 95% CI 1.16–2.17), non-UK or UK travel (OR 1.76, 95% CI 1.40–2.27; OR 1.85, 95% CI 1.35–2.56) and environmental exposures (walking in a paddock, OR 1.82, 95% CI 1.22–2.70; soil contact, OR 1.52, 95% CI 2.13–1.09) suggesting other unmeasured risks, such as person-to-person transmission, could be more important in the most disadvantaged group.
Oats can be processed in a variety of ways ranging from minimally processed such as steel-cut oats (SCO), to mildly processed such as large-flake oats (old fashioned oats, OFO), moderately processed such as instant oats (IO) or highly processed in ready-to-eat oat cereals such as Honey Nut Cheerios (HNC). Although processing is believed to increase glycaemic and insulinaemic responses, the effect of oat processing in these respects is unclear. Thus, we compared the glycaemic and insulinaemic responses elicited by 628 kJ portions of SCO, OFO, IO and HNC and a portion of Cream of Rice cereal (CR) containing the same amount of available-carbohydrate (23 g) as the oatmeals. Healthy males (n 18) and females (n 12) completed this randomised, cross-over trial. Blood was taken fasting and at intervals for 3 h following test-meal consumption. Glucose and insulin peak-rises and incremental AUC (iAUC) were subjected to repeated-measures ANOVA using Tukey’s test (two-sided P<0·05) to compare individual means. Glucose peak-rise (primary endpoint, mean (sem) mmol/l) after OFO, 2·19 (sem 0·11), was significantly less than after CR, 2·61 (sem 0·13); and glucose peak-rise after SCO, 1·93 (sem 0·13), was significantly less than after CR, HNC, 2·49 (sem 0·13) and IO 2·47 (sem 0·13). Glucose iAUC was significantly lower after SCO than CR and HNC. Insulin peak rise was similar among the test meals, but insulin iAUC was significantly less after SCO than IO. Thus, the results show that oat processing affects glycaemic and insulinaemic responses with lower responses associated with less processing.
A set of experimentally obtained “d” values is subject to a variety of random and systematic errors, some of which are inherent to a given diffractometer configuration and some of which may result from incorrect alignment of the diffractometer or technique in establishing peak positions and subsequent calculation of “d” values. In a previous paper (1) we have discussed the problems involved in the identification and control of errors in the computer controlled diffractometer and in that paper we indicated that it is useful to differentiate between different types of two-theta values. Firstly the Theoretical 20 values are those values which are dependant only on the size and distribution of atoms in the unit cell of the phase. The Practical 20 values on the other hand result when aberrations inherent in a given diffractometer geometry are convoluted with the Theoretical 20 values. In terms of their typical magnitudes the most important of these aberrations in decreasing order are: Specimen Displacement, Axial Divergence, Flat Specimen and Transparency Errors. Other inherent errors include refraction and the effects of focal line and receiving slit widths etc., but these latter effects are generally considered small. At the second level, Experimental 20 values also depend on misalignment errors. The third level errors accrue in the conversion of the experimental 20 value to “d” spacing. These errors may arise simply from round-off errors or from more fundamental reasons arising from the polychromatic nature of the source and uncertainties in the wavelength of the diffracted radiation.
During the past three years we have undertaken the development of a complete X-Ray Powder Diffraction, facility with the goal of fully integrating experimental and analytical procedures. Such an approach potentially offers substantially improved performance over previously existing systems by virtue of its internal self-consistency and it opens the possibility of significantly extending analytic procedures for both qualitative and quantitative analyses. Our work to date has resulted in improved performance and significant extensions in both areas, and today I will report on those advances in the area of qualitative analysis.
Growth failure is prevalent among infants with CHD. A Standardized Clinical Assessment and Management Plan was introduced at Boston Children’s Hospital’s cardiac medical ward to identify patients with growth failure, evaluate relevant contributing conditions, and recommend a management plan including collaboration with nutrition physicians.
The objective of this study was to determine whether enrolled patients had improved growth compared with historical controls.
A total of 29 patients were enrolled in the period July, 2013–June, 2014. In all, 42 historical controls who met eligibility criteria for enrolment were selected for comparison from patients admitted to the same ward in the period June, 2010–June, 2011. Patients with CHD aged <1 year , with growth failure defined as weight-for-age z-score <−2, or failure to sustain adequate weight gain were eligible for participation. Primary outcome was change in weight-for-age z-score from enrolment to most recent weight measurement among patients with at least 6 months of follow-up.
Control patients were older at baseline admission weight (118 versus 95 days, p=0.33), and had a higher weight-for-age z-score, −2.9 (−3.1, −2.6) versus −3.7 (−4.3, −3.0) (p=0.02), compared with enrolled patients. Enrolled patients had greater gain in weight-for-age z-score, 2.7 (2.0, 3.4) versus 1.8 (1.5, 2.2) (p=0.03), from baseline to most recent follow-up.
Patients enrolled in a nutrition-focused protocol had greater weight improvement than historical controls. Identification of growth failure and collaboration with a nutrition support team was associated with improved weight gain among CHD patients experiencing growth failure. CHD programmes should consider a structural approach, including nutrition expertise to address growth failure.
A total of 592 people reported gastrointestinal illness following attendance at Street Spice, a food festival held in Newcastle-upon-Tyne, North East England in February/March 2013. Epidemiological, microbiological and environmental investigations were undertaken to identify the source and prevent further cases. Several epidemiological analyses were conducted; a cohort study; a follow-up survey of cases and capture re-capture to estimate the true burden of cases. Indistinguishable isolates of Salmonella Agona phage type 40 were identified in cases and on fresh curry leaves used in one of the accompaniments served at the event. Molecular testing indicated entero-aggregative Escherichia coli and Shigella also contributed to the burden of illness. Analytical studies found strong associations between illness and eating food from a particular stall and with food items including coconut chutney which contained fresh curry leaves. Further investigation of the food supply chain and food preparation techniques identified a lack of clear instruction on the use of fresh uncooked curry leaves in finished dishes and uncertainty about their status as a ready-to-eat product. We describe the investigation of one of the largest outbreaks of food poisoning in England, involving several gastrointestinal pathogens including a strain of Salmonella Agona not previously seen in the UK.
Tuberculosis (TB) is the leading global infectious cause of death. Understanding TB transmission is critical to creating policies and monitoring the disease with the end goal of TB elimination. To our knowledge, there has been no systematic review of key transmission parameters for TB. We carried out a systematic review of the published literature to identify studies estimating either of the two key TB transmission parameters: the serial interval (SI) and the reproductive number. We identified five publications that estimated the SI and 56 publications that estimated the reproductive number. The SI estimates from four studies were: 0.57, 1.42, 1.44 and 1.65 years; the fifth paper presented age-specific estimates ranging from 20 to 30 years (for infants <1 year old) to <5 years (for adults). The reproductive number estimates ranged from 0.24 in the Netherlands (during 1933–2007) to 4.3 in China in 2012. We found a limited number of publications and many high TB burden settings were not represented. Certain features of TB dynamics, such as slow transmission, complicated parameter estimation, require novel methods. Additional efforts to estimate these parameters for TB are needed so that we can monitor and evaluate interventions designed to achieve TB elimination.
Smartphones are increasingly used to access clinical decision support, and many medical applications provide antimicrobial prescribing guidance. However, these applications do not account for local antibiotic resistance patterns and formularies. We implemented an institution-specific antimicrobial stewardship smartphone application and studied patterns of use over a 1-year period.
We evaluated the appropriateness of antibiotic prescriptions for acute sinusitis and pharyngitis. Overall, 81% of antibiotic prescriptions for acute sinusitis were inappropriate and 48% of antibiotic prescriptions for pharyngitis were inappropriate. Types of prescribing errors differed between the 2 infections, including lack of an indication for antibiotics and excessive duration in ~50% of sinusitis cases and incorrect antibiotic dose in ~33% of pharyngitis cases.
Introduction: It is estimated that up to 30% of medical services in Canada are potentially unnecessary, not supported by current evidence or may cause patient harm. This type of practice negatively impacts patients and the healthcare system. Evidence suggests that medical education strongly impacts resource utilization in future practice. Our objective was to integrate Choosing Wisely (CW) recommendations into the undergraduate medical education curriculum to improve students understanding of resource stewardship in their pre-clerkship training. Methods: Post-course survey data and written feedback were collected from the Cumming School of Medicines 2019 class. Qualitative analysis of written feedback was used to identify perceived strengths and areas of improvement to inform additional changes for the 2020 class through a Plan-Do-Study-Act (PDSA) cycle. Results: The post-course survey was completed by 143 students. 60% reported the inclusion of CW improved their ability to develop a clinical management plan. Using the information gathered from the qualitative analysis, we made the following changes for the 2020 class: create an introductory lecture on resource stewardship, incorporate relevant CW recommendations into case study learning objectives, and create standardized slides on CW recommendations for lecturers. Feedback from the 2020 class revealed that the changes were well received and students reported feeling more comfortable with resource stewardship concepts. Conclusion: This data reveals that our efforts have increased students confidence in creating a management plan that integrates resource stewardship and patient safety, and elicited strong faculty support. We will continue to integrate these changes and to obtain student and faculty feedback to help inform additional iterative changes for the subsequent cohort. Our findings are valuable for other medical schools across Canada seeking to incorporate CW material.
In August 2015, Public Health England detected an outbreak of Shiga toxin-producing Escherichia coli (STEC) serotype O157:H7 caused by contaminated salad leaves in a mixed leaf prepacked salad product from a national retailer. The implicated leaves were cultivated at five different farms and the zoonotic source of the outbreak strain was not determined. In March 2016, additional isolates from new cases were identified that shared a recent common ancestor with the outbreak strain. A case–case study involving the cases identified in 2016 revealed that ovine exposures were associated with illness (n = 16; AOR 8·24; 95% CI 1·55–39·74). By mapping the recent movement of sheep and lambs across the United Kingdom, epidemiological links were established between the cases reporting ovine exposures. Given the close phylogenetic relationship between the outbreak strain and the isolates from cases with ovine exposures, it is plausible that ovine faeces may have contaminated the salad leaves via untreated irrigation water or run-off from fields nearby. Timely and targeted veterinary and environmental sampling should be considered during foodborne outbreaks of STEC, particularly where ready to eat vegetables and salads are implicated.
A time-course study was conducted to resolve discrepancies in the literature and better define aspects of the Eimeria maxima life cycle such, as sites of development and both morphology and number of asexual stages. Broiler chickens were inoculated orally with five million E. maxima oocysts (APU1), and were necropsied at regular intervals from 12 to 120 h p.i. Small intestine tissue sections and smears were examined for developmental stages. The jejunum contained the highest numbers of developmental stages. At 12 h p.i., sporozoites were observed inside a parasitophorous vacuole (PV) in the epithelial villi and the lamina propria. By 24 h, sporozoites enclosed by a PV were observed in enterocytes of the glands of Lieberkühn. At 48 h p.i., sporozoites, elongated immature and mature schizonts, were all seen in the glands with merozoites budding off from a residual body. By 60 h, second-generation, sausage-shaped schizonts containing up to 12 merozoites were observed around a residual body in the villar tip of invaded enterocytes. At 72 and 96 h, profuse schizogony associated with third- and fourth-generation schizonts was observed throughout the villus. At 120 h, another generation (fifth) of schizonts were seen in villar tips as well as in subepithelium where gamonts and oocysts were also present; a few gamonts were in epithelium. Our finding of maximum parasitization of E. maxima in jejunum is important because this region is critical for nutrient absorption and weight gain.
The polarization behaviour of radar waves transmitted through two Antarctic ice shelves has been investigated using a step frequency radar with a centre frequency of 300 MHz and a bandwidth of 150 MHz. One site was on Brunt Ice Shelf at a site near Halley station, and 17 sites were on George VI Ice Shelf near the southern ice front. Birefringence in the ice dominated the behaviour on Brunt Ice Shelf, where the anisotropy in the effective permittivity was found to be about 0.14%. On George VI Ice Shelf, a highly anisotropic reflecting surface was the controlling feature, suggesting a fluted ice-shelf base formed by oceanographic currents.
Limitations of access have long restricted exploration and investigation of the cavities beneath ice shelves to a small number of drillholes. Studies of sea-ice underwater morphology are limited largely to scientific utilization of submarines. Remotely operated vehicles, tethered to a mother ship by umbilical cable, have been deployed to investigate tidewater-glacier and ice-shelf margins, but their range is often restricted. The development of free-flying autonomous underwater vehicles (AUVs) with ranges of tens to hundreds of kilometres enables extensive missions to take place beneath sea ice and floating ice shelves. Autosub2 is a 3600 kg, 6.7 m long AUV, with a 1600 m operating depth and range of 400 km, based on the earlier Autosub1 which had a 500 m depth limit. A single direct-drive d.c. motor and five-bladed propeller produce speeds of 1–2 m s−1. Rear-mounted rudder and stern-plane control yaw, pitch and depth. The vehicle has three sections. The front and rear sections are free-flooding, built around aluminium extrusion space-frames covered with glass-fibre reinforced plastic panels. The central section has a set of carbon-fibre reinforced plastic pressure vessels. Four tubes contain batteries powering the vehicle. The other three house vehicle-control systems and sensors. The rear section houses subsystems for navigation, control actuation and propulsion and scientific sensors (e.g. digital camera, upward-looking 300 kHz acoustic Doppler current profiler, 200 kHz multibeam receiver). The front section contains forward-looking collision sensor, emergency abort, the homing systems, Argos satellite data and location transmitters and flashing lights for relocation as well as science sensors (e.g. twin conductivity–temperature–depth instruments, multibeam transmitter, sub-bottom profiler, AquaLab water sampler). Payload restrictions mean that a subset of scientific instruments is actually in place on any given dive. The scientific instruments carried on Autosub are described and examples of observational data collected from each sensor in Arctic or Antarctic waters are given (e.g. of roughness at the underside of floating ice shelves and sea ice).
We present newly acquired airborne radar data showing ice thickness and surface elevation for Pine Island Glacier, Antarctica. These data, when combined with earlier measurements, suggest the presence of a lightly grounded area immediately above the grounding line of Pine Island Glacier. We identify this region as an “ice plain”. It lies close to the centre line of the glacier, has an elevation above buoyancy of <50 m and extends inland for >28 km. The upstream edge of the ice plain is defined by a “coupling line”. The configuration of the ice plain implies that nearby thinning of the ice stream would result in substantial grounding-line retreat. We suggest that the grounding-line retreat of Pine Island Glacier, observed between 1992 and 1996, probably commenced sometime after 1981.
For most common infections requiring hospitalization, antibiotic treatment is completed after hospital discharge. Postdischarge therapy is often unnecessarily broad spectrum and prolonged. We developed an intervention to improve antibiotic selection and shorten treatment durations.
Single center, quasi-experimental retrospective cohort study
Patients prescribed oral antibiotics at hospital discharge before (July 2012–June 2013) and after (October 2014–February 2015) an intervention consisting of (1) institutional guidance for oral step-down antibiotic selection and duration of therapy and (2) pharmacy audit of discharge prescriptions with real-time prescribing recommendations to providers. The primary outcomes measured were total prescribed duration of therapy and use of antibiotics with broad gram-negative activity (ie, fluoroquinolones or amoxicillin-clavulanate).
Overall, 300 cases from the preintervention period and 200 cases from the intervention period were included. Compared with the preintervention period, the use of antibiotics with broad gram-negative activity decreased during the intervention (51% vs 40%; P=.02), particularly fluoroquinolones (38% vs 25%; P=.002). The total duration of therapy decreased from a median of 10 days (interquartile range [IQR], 7–13 days) to 9 days (IQR, 6–13 days) but did not reach statistical significance (P=.13). However, the duration prescribed at discharge declined from 6 days (IQR, 4–10 days) to 5 days (IQR, 3–7 days) (P=.003). During the intervention, there was a nonsignificant increase in the overall appropriateness of discharge prescriptions from 52% to 66% (P=.15).
A multifaceted intervention to optimize antibiotic prescribing at hospital discharge was associated with less frequent use of antibiotics with broad gram-negative activity and shorter postdischarge treatment durations.
We calculate the present ice budget for Antarctica from measurements of accumulation minus iceberg calving, run-off and in situ melting beneath the floating ice shelves. The resulting negative mass balance of 469 Gt year−1 differs substantially from other recent estimates but some components are subject to high temporal variability and budget uncertainties of 20–50%. Annual accumulation from an earlier review is adjusted to include the Antarctic Peninsula for a total of 2144 Gt year−1. An iceberg production rate of 2016 Gt year−1 is obtained from the volume of large icebergs calculated from satellite images since 1978, and from the results of an international iceberg census project. Ice-shelf melting of 544 Gt year−1 is derived from physical and geochemical observations of meltwater outflow, glaciological field studies and modeling of the sub-ice ocean circulation. The highest melt rates occur near ice fronts and deep within sub-ice cavities. Run-off from the ice-sheet surface and from beneath the grounded ice is taken to be 53 Gt year−1. Less than half of the negative mass balance need come from the grounded ice to account for the unattributed 0.45 mm year−1 in the IPCC “best estimate” of the recent global sea-level rise.
To evaluate changes in outpatient fluoroquinolone (FQ) and nitrofurantoin (NFT) use and resistance among E. coli isolates after a change in institutional guidance to use NFT over FQs for acute uncomplicated cystitis.
We compared 2 time periods: January 2003–June 2007 when FQs were recommended as first-line therapy, and July 2007–December 2012, when NFT was recommended. The main outcomes were changes in FQ and NFT use and FQ- and NFT-resistant E. coli by time-series analysis.
Overall, 5,714 adults treated for acute cystitis and 11,367 outpatient E. coli isolates were included in the analysis. After the change in prescribing guidance, there was an immediate 26% (95% CI, 20%–32%) decrease in FQ use (P<.001), and a nonsignificant 6% (95% CI, −2% to 15%) increase in NFT use (P=.12); these changes were sustained over the postintervention period. Oral cephalosporin use also increased during the postintervention period. There was a significant decrease in FQ-resistant E. coli of −0.4% per quarter (95% CI, −0.6% to −0.1%; P=.004) between the pre- and postintervention periods; however, a change in the trend of NFT-resistant E. coli was not observed.
In an integrated healthcare system, a change in institutional guidance for acute uncomplicated cystitis was associated with a reduction in FQ use, which may have contributed to a stabilization in FQ-resistant E. coli. Increased nitrofurantoin use was not associated with a change in NFT resistance.
In October 2014, Public Health England (PHE) identified cases of Shiga toxin-producing Escherichia coli (STEC) serogroup O157 sharing a multiple locus variable-number tandem repeat analysis (MLVA) profile. We conducted a case-control study using multivariable logistic regression to calculate adjusted odds ratios (aOR) and 95% confidence intervals (CI) testing a range of exposures. Cases were defined as laboratory-confirmed STEC O157 with the implicated MLVA profile, were UK residents aged ⩾18 years with symptom onset between 25 September and 30 October 2014, and had no history of travel abroad within 5 days of symptom onset. One hundred and two cases were identified. Cases were mostly female (65%; median age 49, range 2–92 years). It was the second largest outbreak seen in England, to date, and a case-control study was conducted using market research panel controls and online survey methods. These methods were instrumental in the rapid data collection and analysis necessary to allow traceback investigations for short shelf-life products. This is a new method of control recruitment and this is the first in which it was a standalone recruitment method. The case-control study suggested a strong association between consumption of a ready-to-eat food and disease (aOR 28, 95% CI 5·0–157) from one retailer. No reactive microbiological testing of food items during the outbreak was possible due to the short shelf-life of the product. Collaboration with industrial bodies is needed to ensure timely traceback exercises to identify contamination events and initiate appropriate and focused microbiological testing and implement control measures.