Comparing the longer-term effectiveness of a single dose of the Pfizer-BioNTech and Oxford-AstraZeneca COVID-19 vaccines across the age spectrum.

Background: A single dose strategy may be adequate to confer population level immunity and protection against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, especially in low- and middle-income countries where vaccine supply remains limited. We compared the effectiveness of a single dose strategy of the Oxford-AstraZeneca or Pfizer-BioNTech vaccines against SARS-CoV-2 infection across all age groups and over an extended follow-up period. Methods: Individuals vaccinated in North-West London, UK, with either the first dose of the Oxford-AstraZeneca or Pfizer-BioNTech vaccines between January 12, 2021 and March 09, 2021, were matched to each other by demographic and clinical characteristics. Each vaccinated individual was additionally matched to an unvaccinated control. Study outcomes included SARS-CoV-2 infection of any severity, COVID-19 hospitalisation, COVID-19 death, and all-cause mortality. Findings: Amongst matched individuals, 63,608 were in each of the vaccine groups and 127,216 were unvaccinated. Between 14 and 84 days of follow-up after matching, there were 534 SARS-CoV-2 infections, 65 COVID-19 hospitalisations, and 190 deaths, of which 29 were categorized as due to COVID-19. The incidence rate ratio (IRR) for SARS-CoV-2 infection was 0.85 (95% confidence interval [CI], 0.69 to 1.05) for Oxford-Astra-Zeneca, and 0.69 (0.55 to 0.86) for Pfizer-BioNTech. The IRR for both vaccines was the same at 0.25 (0.09 to 0.55) and 0.14 (0.02 to 0.58) for reducing COVID-19 hospitalization and COVID-19 mortality, respectively. The IRR for all-cause mortality was 0.25 (0.15 to 0.39) and 0.18 (0.10 to 0.30) for the Oxford-Astra-Zeneca and Pfizer-BioNTech vaccines, respectively. Age was an effect modifier of the association between vaccination and SARS-CoV-2 infection of any severity; lower hazard ratios for increasing age. Interpretation: A single dose strategy, for both vaccines, was effective at reducing COVID-19 mortality and hospitalization rates. The magnitude of vaccine effectiveness was comparatively lower for SARS-CoV-2 infection, although this was variable across the age range, with higher effectiveness seen with older adults. Our results have important implications for health system planning -especially in low resource settings where vaccine supply remains constrained.

Deep recurrent reinforced learning model to compare the efficacy of targeted local versus national measures on the spread of COVID-19 in the UK.

OBJECTIVES: To prevent the emergence of new waves of COVID-19 caseload and associated mortalities, it is imperative to understand better the efficacy of various control measures on the national and local development of this pandemic in space-time, characterise hotspot regions of high risk, quantify the impact of under-reported measures such as international travel and project the likely effect of control measures in the coming weeks. METHODS: We applied a deep recurrent reinforced learning based model to evaluate and predict the spatiotemporal effect of a combination of control measures on COVID-19 cases and mortality at the local authority (LA) and national scale in England, using data from week 5 to 46 of 2020, including an expert curated control measure matrix, official statistics/government data and a secure web dashboard to vary magnitude of control measures. RESULTS: Model predictions of the number of cases and mortality of COVID-19 in the upcoming 5 weeks closely matched the actual values (cases: root mean squared error (RMSE): 700.88, mean absolute error (MAE): 453.05, mean absolute percentage error (MAPE): 0.46, correlation coefficient 0.42; mortality: RMSE 14.91, MAE 10.05, MAPE 0.39, correlation coefficient 0.68). Local lockdown with social distancing (LD_SD) (overall rank 3) was found to be ineffective in preventing outbreak rebound following lockdown easing compared with national lockdown (overall rank 2), based on prediction using simulated control measures. The ranking of the effectiveness of adjunctive measures for LD_SD were found to be consistent across hotspot and non-hotspot regions. Adjunctive measures found to be most effective were international travel and quarantine restrictions. CONCLUSIONS: This study highlights the importance of using adjunctive measures in addition to LD_SD following lockdown easing and suggests the potential importance of controlling international travel and applying travel quarantines. Further work is required to assess the effect of variant strains and vaccination measures.

The ongoing impact of COVID-19 on adult cardiac surgery and suggestions for safe continuation throughout the pandemic: a review of expert opinions.

OBJECTIVES: To establish the impact of the COVID-19 pandemic on adult cardiac surgery by reviewing current data and use this to establish methods for safely continuing to carry out surgery. METHODS: Conduction of a literature search via PubMed using the search terms: '(adult cardiac OR cardiothoracic OR surgery OR minimally invasive OR sternotomy OR hemi-sternotomy OR aortic valve OR mitral valve OR elective OR emergency) AND (COVID-19 or coronavirus OR SARS-CoV-2 OR 2019-nCoV OR 2019 novel coronavirus OR pandemic)'. Thirty-two articles were selected. RESULTS: Cardiac surgery patients have an increased risk of complications from COVID-19 and require vital finite resources such as intensive care beds, also required by COVID-19 patients. Thus reducing their admission and potential hospital-acquired infection with COVID-19 is paramount. During the peak, only emergencies such as acute aortic dissections were treated, triaging patients according to surgical priority and cancelling all elective procedures. Screening and 2-week quarantine prior to admission were essential changes, alongside additional levels of PPE. Focus was on reducing length of stay and switching to day-cases to reduce post-operative transmission risk, whilst several hospitals adopted 'hot' and 'cold' operating theatres for covid-confirmed and covid-negative patients. CONCLUSIONS: This paper suggests a 'CARDIO' approach for reintroducing elective procedures: 'Care, Assess, Re-Evaluate, Develop, Implement, Overcome'; prioritising the mental and physical health of the workforce, learning from and sharing experiences and objectively prioritising patients to improve case load.

A nationwide survey of UK cardiac surgeons' view on clinical decision making during the coronavirus disease 2019 (COVID-19) pandemic.

BACKGROUND: No firm recommendations are currently available to guide decision making for patients requiring cardiac surgery during the coronavirus disease 2019 (COVID-19) pandemic. Systematic appraisal of senior surgeons' consensus can be used to generate interim recommendations until data from clinical observations become available. Hence, we aimed to collect and quantitatively appraise nationwide UK consultants' opinions on clinical decision making for patients requiring cardiac surgery during the COVID-19 pandemic. METHODS: We E-mailed a Web-based questionnaire to all consultant cardiac surgeons through the Society for Cardiothoracic Surgery in Great Britain and Ireland mailing list on the April 17, 2020, and we predetermined to close the survey on the April 21, 2020. This survey was primarily designed to gather information on UK surgeons' opinions using 12 items. Strong consensus was predefined as an opinion shared by at least 60% of responding consultants. RESULTS: A total of 86 consultant surgeons undertook the survey. All UK cardiac units were represented by at least 1 consultant. Strong consensus was achieved for the following key questions: (1) before any hospital admission for cardiac surgery, nasopharyngeal swab, polymerase chain reaction, and computed tomography of the chest should be performed; (2) the use of full personal protective equipment should to be adopted in every case by the theater team regardless of the patient's COVID-19 status; (3) the risk of COVID-19 exposure for patients undergoing heart surgery should be considered moderate to high and likely to increase mortality if it occurs; and (4) cardiac procedures should be decided based on a rapidly convened multidisciplinary team discussion for every patient. The majority believed that both aortic and mitral surgery should be considered in selected cases. The role of coronary artery bypass graft surgery during the pandemic was controversial. CONCLUSIONS: In this unprecedented pandemic period, this survey provides information for generating interim recommendations until data from clinical observations become available.