Publications by authors named "Alastair McGregor"

Background: COV-BOOST is a multicentre, randomised, controlled, phase 2 trial of seven COVID-19 vaccines used as a third booster dose in June 2021. Monovalent messenger RNA (mRNA) COVID-19 vaccines were subsequently widely used for the third and fourth-dose vaccination campaigns in high-income countries. Real-world vaccine effectiveness against symptomatic infections following third doses declined during the Omicron wave.

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Background: Some high-income countries have deployed fourth doses of COVID-19 vaccines, but the clinical need, effectiveness, timing, and dose of a fourth dose remain uncertain. We aimed to investigate the safety, reactogenicity, and immunogenicity of fourth-dose boosters against COVID-19.

Methods: The COV-BOOST trial is a multicentre, blinded, phase 2, randomised controlled trial of seven COVID-19 vaccines given as third-dose boosters at 18 sites in the UK.

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Objectives: To evaluate the persistence of immunogenicity three months after third dose boosters.

Methods: COV-BOOST is a multicentre, randomised, controlled, phase 2 trial of seven COVID-19 vaccines used as a third booster dose. The analysis was conducted using all randomised participants who were SARS-CoV-2 naïve during the study.

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Background: Few data exist on the comparative safety and immunogenicity of different COVID-19 vaccines given as a third (booster) dose. To generate data to optimise selection of booster vaccines, we investigated the reactogenicity and immunogenicity of seven different COVID-19 vaccines as a third dose after two doses of ChAdOx1 nCov-19 (Oxford-AstraZeneca; hereafter referred to as ChAd) or BNT162b2 (Pfizer-BioNtech, hearafter referred to as BNT).

Methods: COV-BOOST is a multicentre, randomised, controlled, phase 2 trial of third dose booster vaccination against COVID-19.

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Co-existence of multiple drug allergies and pregnancy often results in vexing dilemmas for physicians. A 21-year-old pregnant woman presented with asymptomatic cervicitis with dual infection with and during her third trimester. She reported a history of generalised rash with mucous membrane involvement following use of both macrolides and penicillins.

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Prospective serosurveillance of severe acute respiratory syndrome coronavirus 2 in 1,069 healthcare workers in London, UK, demonstrated that nucleocapsid antibody titers were stable and sustained for <12 weeks in 312 seropositive participants. This finding was consistent across demographic and clinical variables and contrasts with reports of short-term antibody waning.

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Background: The ChAdOx1 nCoV-19 (AZD1222) vaccine has been approved for emergency use by the UK regulatory authority, Medicines and Healthcare products Regulatory Agency, with a regimen of two standard doses given with an interval of 4-12 weeks. The planned roll-out in the UK will involve vaccinating people in high-risk categories with their first dose immediately, and delivering the second dose 12 weeks later. Here, we provide both a further prespecified pooled analysis of trials of ChAdOx1 nCoV-19 and exploratory analyses of the impact on immunogenicity and efficacy of extending the interval between priming and booster doses.

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Objective: The aim of this paper is to describe evolution, epidemiology and clinical outcomes of COVID-19 in subjects tested at or admitted to hospitals in North West London.

Design: Observational cohort study.

Setting: London North West Healthcare NHS Trust (LNWH).

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Objective: To describe the characteristics and outcomes of patients with a clinical diagnosis of COVID-19 and false-negative SARS-CoV-2 reverse transcription-PCR (RT-PCR), and develop and internally validate a diagnostic risk score to predict risk of COVID-19 (including RT-PCR-negative COVID-19) among medical admissions.

Design: Retrospective cohort study.

Setting: Two hospitals within an acute NHS Trust in London, UK.

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Background: A safe and efficacious vaccine against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), if deployed with high coverage, could contribute to the control of the COVID-19 pandemic. We evaluated the safety and efficacy of the ChAdOx1 nCoV-19 vaccine in a pooled interim analysis of four trials.

Methods: This analysis includes data from four ongoing blinded, randomised, controlled trials done across the UK, Brazil, and South Africa.

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Objectives: To describe the prevalence and nature of bacterial co-infections in COVID-19 patients within 48 hours of hospital admission and assess the appropriateness of empirical antibiotic treatment they received.

Methods: In this retrospective observational cohort study, we included all adult non-pregnant patients who were admitted to two acute hospitals in North West London in March and April 2020 and confirmed to have COVID-19 infection within 2 days of admission. Results of microbiological specimens taken within 48 hours of admission were reviewed and their clinical significance was assessed.

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We describe the London community testing programme developed for COVID-19, audit its effectiveness and report patient acceptability and patient adherence to isolation guidance, based upon a survey conducted with participants.Any patients meeting the Public Health England (PHE) case definition for COVID-19 who did not require hospital admission were eligible for community testing. 2,053 patients with suspected COVID-19 were tested in the community between January and March 2020.

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Introduction: Age-related immunosenescence influences the presentation of tuberculosis (TB) in older patients. Here, we explore the clinical and radiological presentation of TB in the elderly and the factors associated with time to treatment for TB.

Methods: This is a retrospective cohort study comparing the clinical, radiological and demographic characteristics of TB patients aged ≥65 years with TB patients aged 18-64 years in a large cohort of TB patients in the UK.

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This study describes the clinical features of a cohort of imported cases of strongyloidiasis and the performance of standard diagnostic techniques for this condition. A total of 413 cases were identified, of whom 86 had microscopically proven infection. In proven cases, 23% had normal eosinophil counts, 19% had negative -specific serology, and 9.

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Background: We describe the clinical features of a cohort of patients with liver abscesses and investigate relationships between clinical, radiological and microbiological findings and mortality.

Methods: Retrospective review of pyogenic (PLA) or amoebic liver abscesses (ALA) diagnosed and treated at a major infectious diseases department in London over 9 years.

Results: One hundred forty-one patient records were identified; 132 (93.

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Liver fluke infections occur in people worldwide. In some low-income regions, a combination of ecological, agricultural, and culinary factors leads to a very high prevalence of infection but, in higher-income regions, infections are uncommon. Infection is associated with substantial morbidity and several liver fluke species are recognised as biological carcinogens.

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2016 TB National Institute for Health and Care Excellence (NICE) guidelines imply that contacts of extrapulmonary TB do not require screening for latent TB infection. At our high TB prevalence site, we identified 189 active cases of TB for whom there were 698 close contacts. 29.

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A 29-year-old man was admitted with fevers, cough, left-sided chest pain and lethargy for 1 week. He had a cardiac transplant 10 years prior and was on immunosuppressive drugs. He was found to have a pulmonary lesion and went on to develop a lung abscess.

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