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1.
Epidemiol Infect ; 150: e201, 2022 Nov 04.
Article in English | MEDLINE | ID: covidwho-2150942

ABSTRACT

The objectives of this study were to define risk factors for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in University of Cambridge (UoC) students during a period of increased incidence in October and November 2020. The study design was a survey.Routine public health surveillance identified an increase in the numbers of UoC students with confirmed SARS-CoV-2 positivity in the 10 days after a national lockdown was announced in the UK on 5th November 2020. Cases were identified both through symptom-triggered testing and a universal asymptomatic testing programme. An online questionnaire was sent to all UoC students on 25 November to investigate risk factors for testing positive in the period after 30th October 2020. This asked about symptoms, SARS-CoV-2 test results, aspects of university life, and attendance at social events in the week prior to lockdown. Univariate and multivariable analyses were undertaken evaluating potential risk factors for SARS-CoV-2 positivity.Among 3980 students responding to the questionnaire, 99 (2.5%) reported testing SARS-CoV-2 positive in the period studied; 28 (28%) were asymptomatic. We found strong independent associations with SARS-CoV-2 positivity and attendance at two social settings in the City of Cambridge (adjusted odds ratio favouring disease 13.0 (95% CI 6.2-26.9) and 14.2 (95% CI 2.9-70)), with weaker evidence of association with three further social settings. By contrast, we did not observe strong independent associations between disease risk and accommodation type or attendance at a range of activities associated with the university curriculum.To conclude attendance at social settings can facilitate widespread SARS-CoV-2 transmission in university students. Constraint of transmission in higher education settings needs to emphasise risks outside university premises, as well as a COVID-safe environment within university premises.

2.
Br Dent J ; 233(8): 653-658, 2022 10.
Article in English | MEDLINE | ID: covidwho-2096673

ABSTRACT

Introduction The COVID-19 pandemic impacted significantly on dental service delivery across England.Objective To explore how and why the pandemic affected antibiotic prescribing by primary care dentists.Methods Mixed-methods study: secondary analysis of routinely collected NHS dental antibiotic prescribing data from before and during the pandemic; and an online survey of dentists (NHS and private) across England's regions.Results Dental antibiotic prescribing increased 22% in the pandemic's first year, with regional variation from a 12.1% increase in London to 29.1% in East of England. Of 159 dentists surveyed, 60% had prescribed 'many more' antibiotics. Some urgent dental centres required antibiotics before accepting referrals, irrespective of clinical appropriateness. Diagnosing remotely was hard. Antibiotics were used to delay aerosol generating procedures and fill gaps in services. Widespread frustration existed.Discussion Maintaining access to urgent dental care during a future pandemic would include availability of high-grade personal protective equipment for dental teams. Everyone must understand the impact of restricted dental access on antibiotic overprescribing and hence antibiotic resistance.Conclusion Reduced dental access and changes in dental service delivery because of the pandemic increased antibiotic prescribing. Ensuring uninterrupted access for all to effective urgent dental care is an important element of global efforts to tackle antibiotic resistance.


Subject(s)
Anti-Bacterial Agents , COVID-19 Drug Treatment , COVID-19 , Humans , Anti-Bacterial Agents/therapeutic use , COVID-19/epidemiology , Pandemics , England/epidemiology , Referral and Consultation
3.
Sci Rep ; 12(1): 4599, 2022 03 29.
Article in English | MEDLINE | ID: covidwho-1931433

ABSTRACT

Dehydration of the upper airways increases risks of respiratory diseases from COVID-19 to asthma and COPD. We find in human volunteer studies involving 464 human subjects in Germany, the US, and India that respiratory droplet generation increases by up to 4 orders of magnitude in dehydration-associated states of advanced age (n = 357), elevated BMI-age (n = 148), strenuous exercise (n = 20) and SARS-CoV-2 infection (n = 87), and falls with hydration of the nose, larynx and trachea by calcium-rich hypertonic salts. We also find in a protocol of exercise-induced airway dehydration that hydration of the airways by calcium-rich salts increases oxygenation relative to a non-treatment control (P < 0.05). In a random control study of COVID-19 positive subjects (n = 40), thrice-a-day delivery of the calcium-rich hypertonic salts (active) suppressed respiratory droplet generation by 51% ± 11% and increased oxygen saturation over three days of treatment by 48.08% ± 9.61% (P < 0.001), while no changes were observed in the nasal-saline control group. Self-reported symptoms significantly declined in the active group and did not decline in the control group. Hydration of the upper airways appears promising as a non-drug approach for reducing risks of respiratory diseases such as COVID-19.


Subject(s)
COVID-19 , Larynx , Exercise , Humans , SARS-CoV-2 , Trachea
4.
Molecular Frontiers Journal ; 5(1n02), 2021.
Article in English | ProQuest Central | ID: covidwho-1752914

ABSTRACT

Dry air alters salt and water balance in the upper airways and increases the risks of COVID-19 among other respiratory diseases. We explored whether such upper airway variations in salt and water balance might alter respiratory droplet generation and potentially contribute to observed impacts of airway hydration on respiratory disease. In a randomized 4-arm study of 21 healthy human subjects we found that the breathing of humid air, the wearing of cotton masks, and the delivery of (sodium, calcium, and magnesium chloride) salt droplets sized to deposit in the nose, trachea, and main bronchi similarly reduce the exhalation of respiratory droplets by approximately 50% (P < 0.05) within 10 minutes following hydration. Respiratory droplet generation returns to relatively high baseline levels within 60–90 minutes on return to dry air in all cases other than on exposure to divalent (calcium and magnesium) salts, where suppression continues for 4–5 hours. We also found via a preliminary ecological regression analysis of COVID-19 cases in the United States between January 2020 and March 2021 that exposure to elevated airborne salt on (Gulf and Pacific) US coastlines appears to suppress by approximately 25%–30% (P < 0.05) COVID-19 incidence and deaths per capita relative to inland counties — accounting for ten potential confounding environmental, physiological, and behavioral variables including humidity. We conclude that the hydration of the upper airways by exposure to humidity, the wearing of masks, or the breathing of airborne salts that deposit in the upper airways diminish respiratory droplet generation and may reduce the risks of COVID-19 incidence and symptoms.

5.
Healthcare (Basel) ; 10(2)2022 Feb 15.
Article in English | MEDLINE | ID: covidwho-1686696

ABSTRACT

COVID-19 is a recent major event, adding to planet Earth's contexts of chaos, crime, injustice, illness, and violence. The HeartMath system has produced research evidence for scientific interventions that alter contexts characterized by chaos and stress, promoting health, coherence, and interconnectedness. This study provides an updated overview of HeartMath as an interdisciplinary, scientific, coherent, integral heart-based healthcare system, operated locally through various initiatives and globally through the Global Coherence Initiative. The HeartMath approach integrates ancient and contemporary, indigenous and mainstream, popular and folk, Eastern, Western, and African forms of healing. The HeartMath interdisciplinary, personal, social, and global vision and mission have considerable theoretical and practical potential for promoting planetary health, education, and development.

6.
Gut ; 70(Suppl 4):A177-A178, 2021.
Article in English | ProQuest Central | ID: covidwho-1506131

ABSTRACT

PTH-14 Figure 1Comparison of percentage of compliance between hospital and home faecal calprotectin test request[Figure omitted. See PDF]ConclusionThe improvement in FC testing compliance with rapid home testing kit compared to laboratory based testing illustrates the benefit of adapting home testing as the standard in future. The considerable increase in compliance by home testing may be due less disruption to patient’s personal life i.e., ability to undergo testing at home, symptoms such as faecal incontinence preventing patients delivering samples to hospital and COVID pandemic compelling patients to stay at home. Adopting rapid FC home testing as standard provides patients with increased locus of control regarding their care, providing health care professionals with rapid results, thus, will improve management of IBD. The ability for patients to perform home test has obvious advantages during the COVID pandemic.ReferencesSands BE. Biomarkers of Inflammation in Inflammatory Bowel Disease. Gastroenterology. 2015 Oct;149(5):1275-1285.e2.Maréchal C, Aimone-Gastin I, Baumann C, Dirrenberger B, Guéant JL, Peyrin-Biroulet L. Compliance with the faecal calprotectin test in patients with inflammatory bowel disease. United European Gastroenterol J. 2017 Aug;5(5):702-707

7.
Sustainability ; 13(17):9981, 2021.
Article in English | MDPI | ID: covidwho-1390773

ABSTRACT

A scientometric analysis of extant literature is conducted to elucidate upon the practicality of teleworking throughout industry as a prelude to prescribing a bespoke conceptual adoption model that embeds innovative digital technologies to facilitate teleworking for construction professionals. The model is premised upon the Royal Institute of British Architects (RIBA) work stages and illustrates how technologies are being used at each incremental stage. An interpretivist philosophy and inductive reasoning were adopted using a sample of longitudinal secondary data contained within pertinent extant literature, where each publication constitutes a unit of analysis. The qualitative scientometric software VOSviewer and Voyant Tools were utilised to examine emergent research trends, with further manual review of prominent papers contained within the sample dataset. Four distinct historical advances are delineated in a timeline that describes the evolution of home working from the 1970s through to the present day (and during the global COVID-19 pandemic). Key milestones delineated indicate how technological advances have created new opportunities for teleworking. The research indicates that an acceleration of digital advances has engendered modernity in contemporary work location patterns and that these offer potentials to reduce the environmental impact of anthropogenic activities. This unique study highlights how COVID-19 and available digital technologies have shaped the future of teleworking from home and the potential environmental impact of such. This concludes by signposting directions for future research into the adoption of teleworking at the organisational level and establishing the cost and environmental savings to businesses from abandoning the traditional model of employer-based working.

8.
J Oral Rehabil ; 48(1): 61-72, 2021 Jan.
Article in English | MEDLINE | ID: covidwho-1388335

ABSTRACT

BACKGROUND: Dental procedures often produce aerosol and splatter which have the potential to transmit pathogens such as SARS-CoV-2. The existing literature is limited. OBJECTIVE(S): To develop a robust, reliable and valid methodology to evaluate distribution and persistence of dental aerosol and splatter, including the evaluation of clinical procedures. METHODS: Fluorescein was introduced into the irrigation reservoirs of a high-speed air-turbine, ultrasonic scaler and 3-in-1 spray, and procedures were performed on a mannequin in triplicate. Filter papers were placed in the immediate environment. The impact of dental suction and assistant presence were also evaluated. Samples were analysed using photographic image analysis and spectrofluorometric analysis. Descriptive statistics were calculated and Pearson's correlation for comparison of analytic methods. RESULTS: All procedures were aerosol and splatter generating. Contamination was highest closest to the source, remaining high to 1-1.5 m. Contamination was detectable at the maximum distance measured (4 m) for high-speed air-turbine with maximum relative fluorescence units (RFU) being: 46,091 at 0.5 m, 3,541 at 1.0 m and 1,695 at 4 m. There was uneven spatial distribution with highest levels of contamination opposite the operator. Very low levels of contamination (≤0.1% of original) were detected at 30 and 60 minutes post-procedure. Suction reduced contamination by 67-75% at 0.5-1.5 m. Mannequin and operator were heavily contaminated. The two analytic methods showed good correlation (r = 0.930, n = 244, P < .001). CONCLUSION: Dental procedures have potential to deposit aerosol and splatter at some distance from the source, being effectively cleared by 30 minutes in our setting.


Subject(s)
COVID-19 , SARS-CoV-2 , Aerosols , Delivery of Health Care , Dental Scaling , Humans
9.
Proc Natl Acad Sci U S A ; 118(27)2021 07 06.
Article in English | MEDLINE | ID: covidwho-1310839
10.
J Dent ; 112: 103746, 2021 09.
Article in English | MEDLINE | ID: covidwho-1307028

ABSTRACT

OBJECTIVES: High-speed dental instruments produce aerosol and droplets. The objective of this study was to evaluate aerosol and droplet production from a novel electric micromotor handpiece (without compressed air coolant) in real world clinical settings. METHODS: 10-minute upper incisor crown preparations were performed in triplicate in an open-plan clinic with mechanical ventilation providing 3.45 air changes per hour. A 1:5 ratio electric micromotor handpiece which allows water coolant without compressed air (Ti-Max Z95L, NSK) was used at three speeds: 60,000 (60 K), 120,000 (120 K), and 200,000 (200 K) revolutions per minute. Coolant solutions contained fluorescein sodium as a tracer (2.65 mmol L - 1). High-speed air-turbine positive control, and negative control conditions were conducted. Aerosol production was evaluated at 3 locations (0.5 m, 1.5 m, and 1.7 m) using: (1) an optical particle counter (OPC; 3016-IAQ, Lighthouse) to detect all aerosol; and (2) a liquid cyclone air sampler (BioSampler, SKC Ltd.) to detect aerosolised fluorescein, which was quantified by spectrofluorometric analysis. Settled droplets were detected by spectrofluorometric analysis of filter papers placed onto a rig across the open-plan clinic. RESULTS: Local (within treatment bay) settled droplet contamination was elevated above negative control for all conditions, with no difference between conditions. Settled droplet contamination was not detected above negative controls outside the treatment bay for any condition. Aerosol detection at 1.5 m and 1.7 m, was only increased for the air-turbine positive control condition. At 0.5 m, aerosol levels were highly elevated for the air-turbine, minimally elevated for 200 K and 120 K, and not elevated for 60 K. CONCLUSIONS: Electric micromotor handpieces which use water-jet coolant alone without compressed air produce localised (within treatment bay) droplet contamination, but are unlikely to produce aerosol contamination beyond the immediate treatment area (1.5 m), allowing them to be used safely in most open-plan clinic settings.


Subject(s)
Dental High-Speed Equipment , Aerosols
11.
Buildings ; 11(7):282, 2021.
Article in English | MDPI | ID: covidwho-1288805

ABSTRACT

Physical contact and respiratory droplet transmission have been widely regarded as the main routes of COVID-19 infection. However, mounting evidence has unveiled the risk of aerosol transmission of the virus. Whereas caution has been taken to avoid this risk in association with clinical facilities, facilities such as spa pools and Jacuzzis, which are characterized by bubble-aerosol generation, high bather loads, and limited turnover rates, may promote aerosol transmission. Focusing on these non-clinical facilities in the built environment, a review study was undertaken. First, the typical water disinfection and ventilation-aided operations for the facilities were illustrated. Second, cross comparisons were made between the applicable standards and guidelines of the World Health Organization and countries including Australia, Canada, China, the United Kingdom, and the United States. The similarities and differences in their water quality specifications, ventilation requirements, and air quality enhancement measures were identified;there were no specific regulations for preventing aerosol transmission at those aerosol-generating facilities. Third, a qualitative review of research publications revealed the emergence of studies on potential air-borne transmission of COVID-19, but research on built facilities posing high risks of aerosol transmission remains scant. This study’s results inform key directions for future research on abating aerosol transmission of COVID-19: the development of bespoke personal protective equipment and engineering and management controls on water quality, ventilation, and air quality.

12.
QRB Discov ; 1: e5, 2020.
Article in English | MEDLINE | ID: covidwho-1287738

ABSTRACT

We propose the nasal administration of calcium-enriched physiological salts as a new hygienic intervention with possible therapeutic application as a response to the rapid and tenacious spread of COVID-19. We test the effectiveness of these salts against viral and bacterial pathogens in animals and humans. We find that aerosol administration of these salts to the airways diminishes the exhalation of the small particles that face masks fail to filter and, in the case of an influenza swine model, completely block airborne transmission of disease. In a study of 10 human volunteers (5 less than 65 years and 5 older than 65 years), we show that delivery of a nasal saline comprising calcium and sodium salts quickly (within 15 min) and durably (up to at least 6 h) diminishes exhaled particles from the human airways. Being predominantly smaller than 1 µm, these particles are below the size effectively filtered by conventional masks. The suppression of exhaled droplets by the nasal delivery of calcium-rich saline with aerosol droplet size of around 10 µm suggests the upper airways as a primary source of bioaerosol generation. The suppression effect is especially pronounced (99%) among those who exhale large numbers of particles. In our study, we found this high-particle exhalation group to correlate with advanced age. We argue for a new hygienic practice of nasal cleansing by a calcium-rich saline aerosol, to complement the washing of hands with ordinary soap, use of a face mask, and social distancing.

13.
Br Dent J ; 229(11): 736, 2020 12.
Article in English | MEDLINE | ID: covidwho-1241909
14.
Clin Transl Immunology ; 10(4): e1269, 2021.
Article in English | MEDLINE | ID: covidwho-1162553

ABSTRACT

OBJECTIVES: Efforts to develop and deploy effective vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continue at pace. Here, we describe rational antigen design through to manufacturability and vaccine efficacy of a prefusion-stabilised spike (S) protein, Sclamp, in combination with the licensed adjuvant MF59 'MF59C.1' (Seqirus, Parkville, Australia). METHODS: A panel recombinant Sclamp proteins were produced in Chinese hamster ovary and screened in vitro to select a lead vaccine candidate. The structure of this antigen was determined by cryo-electron microscopy and assessed in mouse immunogenicity studies, hamster challenge studies and safety and toxicology studies in rat. RESULTS: In mice, the Sclamp vaccine elicits high levels of neutralising antibodies, as well as broadly reactive and polyfunctional S-specific CD4+ and cytotoxic CD8+ T cells in vivo. In the Syrian hamster challenge model (n = 70), vaccination results in reduced viral load within the lung, protection from pulmonary disease and decreased viral shedding in daily throat swabs which correlated strongly with the neutralising antibody level. CONCLUSION: The SARS-CoV-2 Sclamp vaccine candidate is compatible with large-scale commercial manufacture, stable at 2-8°C. When formulated with MF59 adjuvant, it elicits neutralising antibodies and T-cell responses and provides protection in animal challenge models.

15.
Proc Natl Acad Sci U S A ; 118(8)2021 02 23.
Article in English | MEDLINE | ID: covidwho-1075324

ABSTRACT

COVID-19 transmits by droplets generated from surfaces of airway mucus during processes of respiration within hosts infected by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus. We studied respiratory droplet generation and exhalation in human and nonhuman primate subjects with and without COVID-19 infection to explore whether SARS-CoV-2 infection, and other changes in physiological state, translate into observable evolution of numbers and sizes of exhaled respiratory droplets in healthy and diseased subjects. In our observational cohort study of the exhaled breath particles of 194 healthy human subjects, and in our experimental infection study of eight nonhuman primates infected, by aerosol, with SARS-CoV-2, we found that exhaled aerosol particles vary between subjects by three orders of magnitude, with exhaled respiratory droplet number increasing with degree of COVID-19 infection and elevated BMI-years. We observed that 18% of human subjects (35) accounted for 80% of the exhaled bioaerosol of the group (194), reflecting a superspreader distribution of bioaerosol analogous to a classical 20:80 superspreader of infection distribution. These findings suggest that quantitative assessment and control of exhaled aerosol may be critical to slowing the airborne spread of COVID-19 in the absence of an effective and widely disseminated vaccine.


Subject(s)
COVID-19/physiopathology , COVID-19/transmission , Exhalation/physiology , Obesity/physiopathology , Aerosols , Age Factors , Animals , Body Mass Index , COVID-19/epidemiology , COVID-19/virology , Cohort Studies , Humans , Mucus/chemistry , Mucus/virology , Obesity/epidemiology , Obesity/virology , Particle Size , Primates , Respiratory System/metabolism , SARS-CoV-2/isolation & purification , Viral Load
16.
Br Dent J ; 2021 Jan 08.
Article in English | MEDLINE | ID: covidwho-1014999

ABSTRACT

Introduction Dental procedures produce splatter and aerosol which have potential to spread pathogens such as SARS-CoV-2. Mixed evidence exists on the aerosol-generating potential of orthodontic procedures. The aim of this study was to evaluate splatter and/or settled aerosol contamination during orthodontic debonding.Material and methods Fluorescein dye was introduced into the oral cavity of a mannequin. Orthodontic debonding was undertaken with surrounding samples collected. Composite bonding cement was removed using a speed-increasing handpiece with dental suction. A positive control condition included a water-cooled, high-speed air-turbine crown preparation. Samples were analysed using digital image analysis and spectrofluorometric analysis.Results Contamination across the eight-metre experimental rig was 3% of the positive control on spectrofluorometric analysis and 0% on image analysis. Contamination of the operator, assistant and mannequin was 8%, 25% and 28% of the positive control, respectively.Discussion Splatter and settled aerosol from orthodontic debonding is distributed mainly within the immediate locality of the mannequin. Widespread contamination was not observed.Conclusions Orthodontic debonding is unlikely to produce widespread contamination via splatter and settled aerosol, but localised contamination is likely. This highlights the importance of personal protective equipment for the operator, assistant and patient. Further work is required to examine suspended aerosol.

17.
J Dent ; 105: 103565, 2021 02.
Article in English | MEDLINE | ID: covidwho-997116

ABSTRACT

OBJECTIVES: Identify splatter/aerosol distribution from dental procedures in an open plan clinic and explore aerosol settling time after dental procedures. METHODS: In two experimental designs using simulated dental procedures on a mannequin, fluorescein dye was introduced: (1) into the irrigation system of an air-turbine handpiece; (2) into the mannequin's mouth. Filter papers were placed in an open plan clinic to collect fluorescein. An 8-metre diameter rig was used to investigate aerosol settling time. Analysis was by fluorescence photography and spectrofluorometry. RESULTS: Contamination distribution varied across the clinic depending on conditions. Unmitigated procedures have the potential to deposit contamination at large distances. Medium volume dental suction (159 L/min air) reduced contamination in the procedural bay by 53%, and in other areas by 81-83%. Low volume suction (40 L/min air) was similar. Cross-ventilation reduced contamination in adjacent and distant areas by 80-89%. In the most realistic model (fluorescein in mouth, medium volume suction), samples in distant bays (≥5 m head-to-head chair distance) gave very low or zero readings (< 0.0016% of the fluorescein used during the procedure). Almost all (99.99%) of the splatter detected was retained within the procedural bay/walkway. After 10 min, very little additional aerosol settled. CONCLUSIONS: Cross-infection risk from dental procedures in an open plan clinic appears small when bays are ≥ 5 m apart. Dilution effects from instrument water spray were observed, and dental suction is of benefit. Most settled aerosol is detected within 10 min indicating environmental cleaning may be appropriate after this. CLINICAL SIGNIFICANCE: Aerosols produced by dental procedures have the potential to contaminate distant sites and the majority of settled aerosol is detectable after 10 min. Dental suction and ventilation have a substantial beneficial effect. Contamination is likely to be minimal in open plan clinics at distances of 5 m or more.


Subject(s)
COVID-19 , Pandemics , Aerosols , Humans , SARS-CoV-2 , Suction
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