Diagnostic accuracy of the Abbott ID NOW SARS-CoV-2 rapid test for the triage of acute medical admissions.

BACKGROUND: Decisions to isolate patients at risk of having coronavirus disease 2019 (COVID-19) in the emergency department (ED) must be rapid and accurate to ensure prompt treatment and maintain patient flow whilst minimising nosocomial spread. Reverse transcription polymerase chain reaction (RT-PCR) assays are too slow to achieve this, and near-patient testing is being used increasingly to facilitate triage. The ID NOW severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) assay is an isothermal nucleic acid amplification near-patient test which targets the RNA-dependent RNA-polymerase gene. AIM: To assess the diagnostic performance of ID NOW as a COVID-19 triage tool for medical admissions from the ED of a large acute hospital. METHODS: All adult acute medical admissions from the ED between 31st March and 31st July 2021 with valid ID NOW and RT-PCR results were included. The diagnostic accuracy of ID NOW [sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV)] was calculated against the laboratory reference standard. Discrepant results were explored further using cycle threshold values and clinical data. FINDINGS: Two percent (124/6050) of medical admissions were SARS-CoV-2 positive on RT-PCR. Compared with PCR, ID NOW had sensitivity and specificity of 83.1% [95% confidence interval (CI) 75.4-88.7] and 99.5% (95% CI 99.3-99.6), respectively. PPV and NPV were 76.9% (95% CI 69.0-83.2) and 99.6% (95% CI 99.5-99.8), respectively. The median time from arrival in the ED to ID NOW result was 59 min. CONCLUSION: ID NOW provides a rapid and reliable adjunct for the safe triage of patients with COVID-19, and can work effectively when integrated into an ED triage algorithm.

First UK trial of Xenex PX-UV, an automated ultraviolet room decontamination device in a clinical haematology and bone marrow transplantation unit.

BACKGROUND: There is growing interest in the use of no-touch automated room decontamination devices within healthcare settings. Xenex PX-UV is an automated room disinfection device using pulsed ultraviolet (UV) C radiation with a short cycle time. AIM: To investigate the microbiological efficacy of this device when deployed for terminal decontamination of isolation rooms within a clinical haematology unit. METHODS: The device was deployed in isolation rooms in a clinical haematology unit. Contact plates were applied to common touch points to determine aerobic total colony counts (TCCs) and samples collected using Polywipe™ sponges for detection of vancomycin-resistant enterococci (VRE). FINDINGS: The device was easy to transport, easy to use, and it disinfected rooms rapidly. There was a 76% reduction in the TCCs following manual cleaning, with an additional 14% reduction following UV disinfection, resulting in an overall reduction of 90% in TCCs. There was a 38% reduction in the number of sites where VRE was detected, from 26 of 80 sites following manual cleaning to 16 of 80 sites with additional UV disinfection. CONCLUSIONS: The Xenex PX-UV device can offer a simple and rapid additional decontamination step for terminal disinfection of patient rooms. However, the microbiological efficacy against VRE was somewhat limited.

Dynamic regulation of partner abundance mediates response of reef coral symbioses to environmental change.

Regulating partner abunclance may allow symmotic organisms to mediate interaction outcomes, facilitating adaptive responses to environmental change. To explore the capacity for-adaptive regulation in an ecologically important endosymbiosis, we studied the population dynamics of symbiotic algae in reef-building corals under different abiotic contexts. We found high natural variability in symbiont abundance in corals across reefs, but this variability converged to different symbiont-specific abundances when colonies were maintained under constant conditions. When conditions changed seasonally, symbiont abundance readjusted to new equilibria. We explain these patterns using an a priori model of symbiotic costs and benefits to the coral host, which shows that the observed changes in symbiont abundance are consistent with the maximization of interaction benefit under different environmental conditions. These results indicate that, while regulating symbiont abundance helps hosts sustain maximum benefit in a dynamic environment, spatiotemporal variation in abiotic factors creates a broad range of symbiont abundances (and interaction outcomes) among corals that may account for observed natural variability in performance (e.g., growth rate) and stress tolerance (e.g., bleaching susceptibility). This cost or benefit framework provides a new perspective on the dynamic regulation of reef coral symbioses and illustrates that the dependence of interaction outcomes on biotic and abiotic contexts may be important in understanding how diverse mutualisms respond to environmental change.

Phytochemical profile of commercially available food plant powders: their potential role in healthier food reformulations.

Reformulation of existing processed food or formulation of new foods using natural products (plant-based) will inherently confer to new products with less calories, fat, salt, phosphates and other synthetic components, and higher amounts of fibre, antioxidants, vitamins and other beneficial components. Plant ingredients, such as food plant powders, are currently being used in food manufacturing, predominantly for flavouring and colouring purposes. To expand their use as a food ingredient, freeze-dried powders representing major vegetable groups were characterised by targeted LC-MS/MS analysis of their phytochemicals. All the plant powders were found to be rich in flavonoids, phenolic acids and derivatives; total content in these compounds varied from around 130 mg kg(-1) (green pea) to around 930 mg kg(-1) (spinach). The food plant powders' phytochemical content represents valuable information for the food industry in the development of healthier novel foods and for the reformulation of existing food products in relation to antioxidants, food preservatives and alternatives to nitrite use.

Outbreak of invasive group A streptococcus infection: contaminated patient curtains and cross-infection on an ear, nose and throat ward.

BACKGROUND: Outbreaks of group A streptococcus (GAS) infections may occur in healthcare settings and have been documented in surgical, obstetrics and gynaecology, and burns units. The environment may serve as a reservoir and facilitate transmission via contaminated equipment. AIM: To describe the investigation and control of an outbreak of healthcare-associated GAS infection on an ear, nose and throat (ENT) ward in a tertiary referral centre. METHODS: Two patients with laryngeal cancer developed invasive GAS infection (bacteraemia) with associated tracheostomy wound cellulitis within a 48 h period. The outbreak team undertook an investigation involving a retrospective review of GAS cases, prospective case finding, healthcare worker screening and sampling of patient curtains. Immediate control measures included source isolation, a thorough rolling clean with a chlorine-based disinfectant and hydrogen peroxide decontamination of patient equipment. FINDINGS: Prospective patient screening identified one additional patient with carriage of GAS from a tracheostomy wound swab. Staff screening identified one healthcare worker who acquired GAS during the outbreak and who subsequently developed pharyngitis. Environmental sampling demonstrated that 10 out of 34 patient curtains on the ward were contaminated with GAS and all isolates were typed as emm-1. CONCLUSION: This is the first outbreak report to demonstrate patient curtains as potential source for GAS cross-transmission, with implications in relation to hand hygiene and frequency of laundering. Based on this report we recommend that during an outbreak of GAS infection all patient curtains should be changed as part of the enhanced decontamination procedures.

Impact of an educational intervention upon the hand hygiene compliance of children.

BACKGROUND: Hand hygiene compliance is the single most effective way to reduce healthcare-associated infections. Children are notoriously vulnerable to infection as well as acting as conduits to transmission. Based on these observations, the authors formulated the hypothesis that behavioural change which improved children's hand hygiene compliance would decrease the spread of infectious diseases. AIM: To create an educational intervention to induce long-term behavioural change culminating in increased hand hygiene compliance of children, and thus a decrease in the rate of infections. METHODS: Focus groups conducted during interactive teaching sessions identified what children felt would help them to increase their hand hygiene compliance. This informed the design of an educational device that was subsequently trialled to measure its effectiveness in increasing hand hygiene compliance. Initial developmental stages were conducted in two schools in the East Midlands with study participants aged 5-8 years; the device was subsequently used in a healthcare setting to assess deployment flexibility. FINDINGS: Focus groups indicated that children enjoyed interactive learning, developed knowledge about cross-transmission of infections, and became motivated to encourage others to improve hand hygiene compliance. Microbiological swabbing verified the presence of pathogens on children's hands and environmental surfaces that could serve as reservoirs of infection, and questionnaires indicated an increase in handwashing following the intervention. CONCLUSION: Educational interventions have the potential to increase hand hygiene and reduce the transmission of infections.

First UK evaluation of an automated ultraviolet-C room decontamination device (Tru-D™).

Tru-D™ is an automated room disinfection device that uses ultraviolet-C radiation to kill micro-organisms. The device was deployed in six side-rooms and an operating theatre. In a cleaned, unoccupied operating theatre, Tru-D eradicated all organisms from the environment. Using artificially seeded Petri dishes with meticillin-resistant Staphylococcus aureus, multi-resistant acinetobacter and vancomycin-resistant enterococci, the mean log10 reductions were between three and four when used at 22,000µWs/cm(2) reflected dose. The device was easy to transport and utilize, and able to disinfect rooms rapidly. This appears to be a practical alternative technology to other 'no-touch' automated room disinfection systems.

Twenty-four-hour observational study of hospital hand hygiene compliance.

This observational study measured healthcare workers' (HCWs'), patients' and visitors' hand hygiene compliance over a 24h period in two hospital wards using the 'five moments of hand hygiene' observation tool. Hand hygiene is considered to be the most effective measure in reducing healthcare-associated infections but studies have reported suboptimal levels of compliance. Most studies have used random observational time-periods for data collection and this has been criticised. We monitored a total of 823 hand hygiene opportunities (HCWs, N=659; patients and visitors, N=164). Among HCWs, compliance was 47% for doctors, 75% for nurses, 78% for allied health professionals, and 59% for ancillary and other staff (P<0.001). There was no difference in compliance between patients and visitors (56% vs 57%, P=0.87). Hand hygiene compliance varied depending on which of the five moments of hygiene HCWs had undertaken (P<0.001), with compliance before an aseptic task being 100% (3/3); after body fluid exposure 93% (86/93); after patient contact 80% (114/142); before patient contact 68% (196/290); and after contact with surroundings 50% (65/129). Lower levels of compliance were found for HCWs working during the early shift (P<0.001). For patients and visitors there was no evidence of an association between moments of hygiene and compliance. Levels of compliance were higher compared with previous reported estimates. Medical staff had the lowest level of compliance and this continues to be a concern which warrants specific future interventions.

Sensitivity of markers of DNA stability and DNA repair activity to folate supplementation in healthy volunteers.

We have previously reported that supplementation with folic acid (1.2 mg day(-1) for 12 week) elicited a significant improvement in the folate status of 61 healthy volunteers. We have examined effects of this supplement on markers of genomic stability. Little is known about the effect of folate supplementation on DNA stability in a cohort, which is not folate deficient. Preintervention, there was a significant inverse association between uracil misincorporation in lymphocyte DNA and red cell folate (P < 0.05). In contrast, there were no associations between folate status and DNA strand breakage, global DNA methylation or DNA base excision repair (measured as the capacity of the lymphocyte extract to repair 8-oxoGua ex vivo). Folate supplementation elicited a significant reduction in uracil misincorporation (P < 0.05), while DNA strand breakage and global DNA methylation remained unchanged. Increasing folate status significantly decreased the base excision repair capacity in those volunteers with the lowest preintervention folate status (P < 0.05). Uracil misincorporation was more sensitive to changes in folate status than other measures of DNA stability and therefore could be considered a specific and functional marker of folate status, which may also be relevant to cancer risk in healthy people.

Workplace protection of air-fed visors used in paint spraying operations.

Air-fed visors are commonly used for protection against exposure to airborne isocyanates during paint spraying. Protection levels for this class of equipment are theoretically adequate, yet isocyanate sensitization in this occupation still occurs. The work reported here set out to establish the level of respiratory protection that is achieved during real paint spraying activities when air-fed visors are used. The work also examined the effects of reduced air supply flow rates on this type of respiratory protection. The workplace study highlighted common problems that occur when attempting to measure protection factors, and process and interpret the collected data. Many of the environments included in this study did not exhibit challenge concentrations high enough to reliably measure the workplace protection factor of this class of device. When detection limits are taken into consideration, the remaining field data suggest that an assigned protection factor in the region of 40 may be appropriate. When well maintained and used in accordance with the manufacturer's instructions, air-fed visors are capable of providing a good level of respiratory protection. The protection given by air-fed visors is strongly dependent on the air flow supplied to them. Laboratory measurements demonstrate that protection falls as the air supply falls. This is a gradual process and does not suddenly occur at any particular air supply flow. Observations made during the field tests indicate that there may be other activities associated with the spraying process that need to be taken into consideration when looking for sources of respiratory sensitization.

Meaningful workplace protection factor measurement: experimental protocols and data treatment.

Workplace performance measurement of respiratory protective equipment (RPE) is fundamental to the understanding of how well wearers are protected. It forms the basis for guidance on which the selection of appropriate equipment is based. However, the measurement of this performance is open to many sources of interference and inaccuracy, reducing the value and relevance of the results, and is most difficult for devices providing the highest levels of protection. In this paper, a method for critically assessing collected workplace protection factor (WPF) data is validated. This method rejects unreliable data, using criteria based on the detection limits of the analytical measurement system. An iterative approach is also described which arrives at a supportable estimate of given non-parametric percentiles of the distribution of measured WPFs [such as the fifth percentile, conventionally taken to be the assigned protection factor (APF)]. Further pragmatic criteria, based on a combination of experimental experience and consideration from first principles, are suggested as the basis for any future studies of RPE performance. These will maximize the chances of valid measurements being made, and also provide insight into the level of confidence which can be placed on any of the results. A consequence of these criteria is that typical working environments and measurement methods are incapable of generating WPF data which can be considered reliable.

The evolution of diabetes information systems.

Diabetes information systems have already evolved rapidly in recent years along a developmental pathway initiated by the St Vincent Declaration, fuelled by the rapid pace of IT development in the 1990s and now endorsed by the emerging NHS information strategy. They will be central to the delivery of 'patient-centred' care and essential to supporting and monitoring the diabetes national service framework implementation. Widespread experience has identified three key principles. Firstly the need for a core data set that supports both service delivery and quality development. Secondly, because of the multiprofessional, multisector nature of diabetes care, there is a need to reconcile information from many diverse sources into unitary diabetes care records. Thirdly the crucial importance of making data collection a by-product of every day care delivery (i.e. no duplicate data entry). The work of many local innovators, allied to the increasing experience of the Diabetes UK sponsored UKDIABS project has generated substantial expertise. With the aid of new extraction/analysis tools such as QUIDS and a consistent approach to assessment, this work has hopefully laid secure foundations for monitoring the implementation of the national service framework. Furthermore, parallel developments under the aegis of the National electronic Library for Health (NeLH) should enable those involved with diabetes care to access relevant knowledge and information with ease. Increasingly user friendly ways by which patients can interact with their electronic records and linked knowledge sources will create many new opportunities. Diabetes information systems are likely to be at the forefront of diabetes care delivery in the future, providing patients and professionals with timely and accurate data for the organization and delivery of care.

Performance of power assisted respirators during simulated asbestos removal.

Protection factors were measured on full face mask power assisted respirators when worn by experienced asbestos removal operatives under simulated asbestos removal work conditions. The sulfur hexafluoride test method as defined in European Standards was employed to determine the leakage into the respirators. Protection factors were measured on a total of 21 test volunteers. The test method allowed protection factors to be related to wearer activities and practices. Poor fitting techniques and simulated reduction in the respirator's performance resulted in a reduction in the protection factor. Visual inspection of the RPE usually worn by the volunteers identified inadequate maintenance. This study re-emphasises that careful selection, facepiece fit testing and correct use and maintenance of RPE are essential to ensure optimum protection to the wearer.

Food intake and body measurements of Atlantic bottlenose dolphins (Tursiops truncates) in captivity.

The food consumption (recorded in kg of individual fish species), body length and mass of 11 Atlantic bottlenose dolphins kept first at Windsor Safari Park, UK (1979-1993/1994), and later at Harderwijk Marine Mammal Park, The Netherlands (1993/1994-1995) are reported. This broad-scale, longitudinal study is based on historical data that were originally recorded for short-term husbandry purposes. The chemical composition and caloric value of the diet were variable and were not recorded. The food intake quantities should therefore be viewed as rough weight estimates of what wild conspecifics might eat (depending on their diet). The average annual food consumption of adult males and non-pregnant, non-lactating females was approximately 2000 kg of fish (estimated at 176 x 10(5) kJ). Food consumption showed little increase during gestation, but was 58-97% higher during lactation than during similar periods in non-reproductive years. All six calves began to eat solid food within a year of birth although suckling continued for 14-37 months after birth. The pattern of food intake of mothers and calves varied substantially between suckling periods. No seasonal changes in food consumption were detected, although there were small seasonal changes in water temperature. Births occurred at various times of year, since the timing of mating varied between years. The animals' body length increased rapidly during the first 3 years of life after which the growth rate decreased. Body length reached asymptote at approximately 270 cm. Adults of both sexes weighed around 260 kg. The relationship between standard body length (in cm) and body mass (in kg), although based on a small sample size (n = 16), can be expressed as body mass = 17.261e(0.0156(body length-100)). Animals weighing 155-225 kg consumed between 2 and 4% of their body mass per day.

The influence of three acoustic alarms on the behaviour of harbour porpoises (Phocoena phocoena) in a floating pen.

Harbour porpoise bycatch may be reduced by deterring porpoises from nets acoustically. In this study, two harbour porpoises were subjected to three acoustic alarms. The effect of each alarm was judged by comparing the animals' position and respiration rate during a test period with that during a baseline period. The XP-10 alarm produced 0.3 s tonal signals randomly selected from a set of 16 with fundamental frequencies between 9 and 15 kHz, with a constant pulse interval of 4.8 s (duty cycle 6%). The 2MP alarm produced 0.3 s tonal signals randomly selected from a set of 16 with similar fundamental frequencies but with random pulse intervals of between 2 and 5 s (duty cycle 8%). The frequency spectra and source levels of the 2MP and XP-10 alarms varied depending on the signal selected. The HS20-80 alarm produced a constant, but asymmetrical frequency modulated sinewave between 20 and 80 kHz with total pulse duration of 0.3 s. with random pulse intervals of between 2 and 5 s (duty cycle 4.6%). The porpoises reacted to all three alarms by swimming away from them and by increasing their respiration rate. The XP-10, which on average had the highest source level, had the strongest effect.