• COVID-19
• Research dataclose
• Research softwareclose
• Other research productsclose
• 2013-2022close
• Restricted close
• Other ORP type close
• English close

An extended brief overviewing a bread swath of responses from higher educational institutions worldwide, to the COVID-19 pandemic.

Background: Our March 2021 edition of this review showed thoracic imaging computed tomography (CT) to be sensitive and moderately specific in diagnosing COVID-19 pneumonia. This new edition is an update of the review. Objectives: Our objectives were to evaluate the diagnostic accuracy of thoracic imaging in people with suspected COVID-19; assess the rate of positive imaging in people who had an initial reverse transcriptase polymerase chain reaction (RT-PCR) negative result and a positive RT-PCR result on follow-up; and evaluate the accuracy of thoracic imaging for screening COVID-19 in asymptomatic individuals. The secondary objective was to assess threshold effects of index test positivity on accuracy. Search methods: We searched the COVID-19 Living Evidence Database from the University of Bern, the Cochrane COVID-19 Study Register, The Stephen B. Thacker CDC Library, and repositories of COVID-19 publications through to 17 February 2021. We did not apply any language restrictions. Selection criteria: We included diagnostic accuracy studies of all designs, except for case-control, that recruited participants of any age group suspected to have COVID-19. Studies had to assess chest CT, chest X-ray, or ultrasound of the lungs for the diagnosis of COVID-19, use a reference standard that included RT-PCR, and report estimates of test accuracy or provide data from which we could compute estimates. We excluded studies that used imaging as part of the reference standard and studies that excluded participants with normal index test results. Data collection and analysis: The review authors independently and in duplicate screened articles, extracted data and assessed risk of bias and applicability concerns using QUADAS-2. We presented sensitivity and specificity per study on paired forest plots, and summarized pooled estimates in tables. We used a bivariate meta-analysis model where appropriate. Main results: We included 98 studies in this review. Of these, 94 were included for evaluating the diagnostic accuracy of thoracic imaging in the evaluation of people with suspected COVID-19. Eight studies were included for assessing the rate of positive imaging in individuals with initial RT-PCR negative results and positive RT-PCR results on follow-up, and 10 studies were included for evaluating the accuracy of thoracic imaging for imagining asymptomatic individuals. For all 98 included studies, risk of bias was high or unclear in 52 (53%) studies with respect to participant selection, in 64 (65%) studies with respect to reference standard, in 46 (47%) studies with respect to index test, and in 48 (49%) studies with respect to flow and timing. Concerns about the applicability of the evidence to: participants were high or unclear in eight (8%) studies; index test were high or unclear in seven (7%) studies; and reference standard were high or unclear in seven (7%) studies. Imaging in people with suspected COVID-19. We included 94 studies. Eighty-seven studies evaluated one imaging modality, and seven studies evaluated two imaging modalities. All studies used RT-PCR alone or in combination with other criteria (for example, clinical signs and symptoms, positive contacts) as the reference standard for the diagnosis of COVID-19. For chest CT (69 studies, 28285 participants, 14,342 (51%) cases), sensitivities ranged from 45% to 100%, and specificities from 10% to 99%. The pooled sensitivity of chest CT was 86.9% (95% confidence interval (CI) 83.6 to 89.6), and pooled specificity was 78.3% (95% CI 73.7 to 82.3). Definition for index test positivity was a source of heterogeneity for sensitivity, but not specificity. Reference standard was not a source of heterogeneity. For chest X-ray (17 studies, 8529 participants, 5303 (62%) cases), the sensitivity ranged from 44% to 94% and specificity from 24 to 93%. The pooled sensitivity of chest X-ray was 73.1% (95% CI 64. to -80.5), and pooled specificity was 73.3% (95% CI 61.9 to 82.2). Definition for index test positivity was not found to be a source of heterogeneity. Definition for index test positivity and reference standard were not found to be sources of heterogeneity. For ultrasound of the lungs (15 studies, 2410 participants, 1158 (48%) cases), the sensitivity ranged from 73% to 94% and the specificity ranged from 21% to 98%. The pooled sensitivity of ultrasound was 88.9% (95% CI 84.9 to 92.0), and the pooled specificity was 72.2% (95% CI 58.8 to 82.5). Definition for index test positivity and reference standard were not found to be sources of heterogeneity. Indirect comparisons of modalities evaluated across all 94 studies indicated that chest CT and ultrasound gave higher sensitivity estimates than X-ray (P = 0.0003 and P = 0.001, respectively). Chest CT and ultrasound gave similar sensitivities (P=0.42). All modalities had similar specificities (CT versus X-ray P = 0.36; CT versus ultrasound P = 0.32; X-ray versus ultrasound P = 0.89). Imaging in PCR-negative people who subsequently became positive. For rate of positive imaging in individuals with initial RT-PCR negative results, we included 8 studies (7 CT, 1 ultrasound) with a total of 198 participants suspected of having COVID-19, all of whom had a final diagnosis of COVID-19. Most studies (7/8) evaluated CT. Of 177 participants with initially negative RT-PCR who had positive RT-PCR results on follow-up testing, 75.8% (95% CI 45.3 to 92.2) had positive CT findings. Imaging in asymptomatic PCR-positive people. For imaging asymptomatic individuals, we included 10 studies (7 CT, 1 X-ray, 2 ultrasound) with a total of 3548 asymptomatic participants, of whom 364 (10%) had a final diagnosis of COVID-19. For chest CT (7 studies, 3134 participants, 315 (10%) cases), the pooled sensitivity was 55.7% (95% CI 35.4 to 74.3) and the pooled specificity was 91.1% (95% CI 82.6 to 95.7). Authors' conclusions: Chest CT and ultrasound of the lungs are sensitive and moderately specific in diagnosing COVID-19. Chest X-ray is moderately sensitive and moderately specific in diagnosing COVID-19. Thus, chest CT and ultrasound may have more utility for ruling out COVID-19 than for differentiating SARS-CoV-2 infection from other causes of respiratory illness. The uncertainty resulting from high or unclear risk of bias and the heterogeneity of included studies limit our ability to confidently draw conclusions based on our results.

ImagineThe internet stops workingelectricity is cutthe many screens which connect you to the world turn blackyou no longer have access to your bank accountor functioning credits cardsthe walls behind which you retreated fade awayand you find yourself under the open skynow you are like menothing but a “dangerous body” on the streetwhat can you do now?what must you do now?out in the open where an invisible virus lurks?you roamroam the city forfoodinformationand means to protect those you love

Abstract In this work, we formulate and analyze a new mathematical model for COVID-19 epidemic with isolated class in fractional order. This model is described by a system of fractional-order differential equations model and includes five classes, namely, S (susceptible class), E (exposed class), I (infected class), Q (isolated class), and R (recovered class). Dynamics and numerical approximations for the proposed fractional-order model are studied. Firstly, positivity and boundedness of the model are established. Secondly, the basic reproduction number of the model is calculated by using the next generation matrix approach. Then, asymptotic stability of the model is investigated. Lastly, we apply the adaptive predictor–corrector algorithm and fourth-order Runge–Kutta (RK4) method to simulate the proposed model. Consequently, a set of numerical simulations are performed to support the validity of the theoretical results. The numerical simulations indicate that there is a good agreement between theoretical results and numerical ones.

Purpose – The COVID-19 has brought with it valuable opportunities for the retail sector. Notably, online channels have assumed a key role for businesses that can rely less on physical channels due to the pandemic’s restrictions. Within this context, the study aims to identify the main antecedents leading to the formation of the male and female customers’ continuance intention of using online food delivery services (OFDS) in the restaurant industry. Design/methodology/approach – A web-based self-completion survey and a subsequent structural equation modelling have been employed on a sample of 360 participants. Findings – Findings reveal that perceived healthiness, quarantine procedures, perceived hygiene, perceived ease of app use and attitude significantly influence continuance intention. Moreover, the moderator analysis corroborates that male consumers’ continuance intention is mainly influenced by perceived healthiness, quarantine procedures and perceived hygiene. Conversely, female customers’ continuance intention is predicated on perceived healthiness and attitude. Research limitations/implications – Although the adoption of a sample of young customers (18–29 years) guarantees good research internal validity, findings are not generalizable. Practical implications – The study provides valuable contributions for restaurants related to the (1) creation/management of their own OFDS platforms; (2) selection of the right third-party platforms. Originality/value – The paper is one of the first studies examining the predictors impacting on customers’ OFDS continuance intention in the COVID-19 context by also focusing on gender differences.

Interviews from Manara DF, Villa G, Korelic L, Arrigoni C, Dellafiore F, Milani V, Ghizzardi G, Magon A, Giannetta N, Caruso R. One-week longitudinal daily description of moral distress, coping, and general health in healthcare workers during the first wave of the COVID-19 outbreak in Italy: A quantitative diary study. Acta Biomed. 2021 Oct 5;92(S6):e2021461. doi: 10.23750/abm.v92iS6.12313. PMID: 34739455. Abstract Background and aim of the work .The fluctuation from day to day within a working week of moral distress, coping, and general health of frontline healthcare workers (HCWs) in facing the challenges of the COVID-19 pandemic has been poorly studied. This study described the weekly fluctuation from day to day of moral distress, coping, and general health in frontline HCWs who worked during the first epidemic wave (May-June 2020) of the COVID-19 pandemic in Italy. Methods: This study has an intensive longitudinal design, and a convenience sampling procedure was employed to enroll physicians, nurses, allied health professions, and healthcare assistants. Data collection was performed using diary encompassed four sections: a socio-demographic form (required only at the baseline data collection) and three scales to assess moral distress, coping, and general health. Results: Results confirmed poor perceived health and mild moral distress in frontline HCWs, especially in HCWs with offspring, during the initial phases of the COVID-19 pandemic and the stability of their daily perception over a working week regarding moral distress, general health, and avoidant coping strategy, while approach coping strategy reported a slight fluctuation over time. Conclusions: Accordingly, on the one hand, these results confirm that outcomes regarding mental health and moral distress are pretty stable and provide insights, on the other hand, regarding the possible organizational interventions to support approach coping strategy as it seems more susceptible to variation over time.