Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 25
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-22283578

RESUMO

BackgroundLow-dose corticosteroids have been shown to reduce mortality for hypoxic COVID-19 patients requiring oxygen or ventilatory support (non-invasive mechanical ventilation, invasive mechanical ventilation or extra-corporeal membrane oxygenation). We evaluated the use of a higher dose of corticosteroids in this patient group. MethodsThis randomised, controlled, open-label platform trial (Randomised Evaluation of COVID-19 Therapy [RECOVERY]) is assessing multiple possible treatments in patients hospitalised for COVID-19. Eligible and consenting adult patients with clinical evidence of hypoxia (i.e. receiving oxygen or with oxygen saturation <92% on room air) were randomly allocated (1:1) to either usual care with higher dose corticosteroids (dexamethasone 20 mg once daily for 5 days followed by 10 mg once daily for 5 days or until discharge if sooner) or usual standard of care alone (which includes dexamethasone 6 mg once daily for 10 days or until discharge if sooner). The primary outcome was 28-day mortality. On 11 May 2022, the independent Data Monitoring Committee recommended stopping recruitment of patients receiving no oxygen or simple oxygen only to this comparison due to safety concerns. We report the results for these participants only. Recruitment of patients receiving ventilatory support continues. The RECOVERY trial is registered with ISRCTN (50189673) and clinicaltrials.gov (NCT04381936). FindingsBetween 25 May 2021 and 12 May 2022, 1272 COVID-19 patients with hypoxia and receiving no oxygen (1%) or simple oxygen only (99%) were randomly allocated to receive usual care plus higher dose corticosteroids versus usual care alone (of whom 87% received low dose corticosteroids during the follow-up period). Of those randomised, 745 (59%) were in Asia, 512 (40%) in the UK and 15 (1%) in Africa. 248 (19%) had diabetes mellitus. Overall, 121 (18%) of 659 patients allocated to higher dose corticosteroids versus 75 (12%) of 613 patients allocated to usual care died within 28 days (rate ratio [RR] 1{middle dot}56; 95% CI 1{middle dot}18-2{middle dot}06; p=0{middle dot}0020). There was also an excess of pneumonia reported to be due to non-COVID infection (10% vs. 6%; absolute difference 3.7%; 95% CI 0.7-6.6) and an increase in hyperglycaemia requiring increased insulin dose (22% vs. 14%; absolute difference 7.4%; 95% CI 3.2-11.5). InterpretationIn patients hospitalised for COVID-19 with clinical hypoxia but requiring either no oxygen or simple oxygen only, higher dose corticosteroids significantly increased the risk of death compared to usual care, which included low dose corticosteroids. The RECOVERY trial continues to assess the effects of higher dose corticosteroids in patients hospitalised with COVID-19 who require non-invasive ventilation, invasive mechanical ventilation or extra-corporeal membrane oxygenation. FundingUK Research and Innovation (Medical Research Council) and National Institute of Health and Care Research (Grant ref: MC_PC_19056), and Wellcome Trust (Grant Ref: 222406/Z/20/Z).

2.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-22280285

RESUMO

BackgroundDimethyl fumarate (DMF) is an anti-inflammatory drug that has been proposed as a treatment for patients hospitalised with COVID-19 MethodsThis randomised, controlled, open-label platform trial (Randomised Evaluation of COVID-19 Therapy [RECOVERY]), is assessing multiple possible treatments in patients hospitalised for COVID-19. In this initial assessment of DMF, performed at 27 UK hospitals, eligible and consenting adults were randomly allocated (1:1) to either usual standard of care alone or usual standard of care plus DMF 120mg twice daily for 2 days followed by 240mg twice daily for 8 days, or until discharge if sooner. The primary outcome was clinical status on day 5 measured on a seven-point ordinal scale, assessed using a proportional odds model. Secondary outcomes were time to sustained improvement in clinical status, time to discharge, day 5 peripheral blood oxygenation, day 5 C-reactive protein, and improvement in day 10 clinical status. The trial is registered with ISRCTN (50189673) and clinicaltrials.gov (NCT04381936). FindingsBetween 2 March 2021 and 18 November 2021, 713 patients were enrolled in the DMF evaluation, of whom 356 were randomly allocated to receive usual care plus DMF, and 357 to usual care alone. 95% of patients were receiving corticosteroids as part of routine care. There was no evidence of a beneficial effect of DMF on clinical status at day 5 (common odds ratio of unfavourable outcome 1.12; 95% CI 0.85-1.46; p=0.42). There was no significant effect of DMF on any secondary outcome. As expected, DMF caused flushing and gastrointestinal symptoms, each in around 6% of patients, but no new adverse effects were identified. InterpretationIn adults hospitalised with COVID-19, DMF was not associated with an improvement in clinical outcomes. FundingUK Research and Innovation (Medical Research Council) and National Institute of Health Research (Grant ref: MC_PC_19056).

3.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-22275865

RESUMO

Both infection and vaccination, alone or in combination, generate antibody and T cell responses against SARSCoV2. However, the maintenance of such responses, and hence protection from disease, requires careful characterisation. In a large prospective study of UK healthcare workers (Protective immunity from T cells in Healthcare workers (PITCH), within the larger SARSCoV2 immunity and reinfection evaluation (SIREN) study) we previously observed that prior infection impacted strongly on subsequent cellular and humoral immunity induced after long and short dosing intervals of BNT162b2 (Pfizer/BioNTech) vaccination. Here, we report longer follow up of 684 HCWs in this cohort over 6-9 months following two doses of BNT162b2 or AZD1222 (Oxford/AstraZeneca) vaccination and up to 6 months following a subsequent mRNA booster vaccination. We make three observations: Firstly, the dynamics of humoral and cellular responses differ; binding and neutralising antibodies declined whereas T and memory B cell responses were maintained after the second vaccine dose. Secondly, vaccine boosting restored IgG levels, broadened neutralising activity against variants of concern including omicron BA.1, BA.2 and BA.5, and boosted T cell responses above the 6 month level post dose 2. Thirdly, prior infection maintained its impact driving larger as well as broader T cell responses compared with never-infected people, a feature maintained until 6 months after the third dose. In conclusion, broadly cross-reactive T cell responses are well maintained over time, especially in those with combined vaccine and infection-induced immunity (hybrid immunity), and may contribute to continued protection against severe disease.

4.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-22271623

RESUMO

BackgroundWe evaluated the use of baricitinib, a Janus kinase (JAK) 1/2 inhibitor, for the treatment of patients admitted to hospital because of COVID-19. MethodsThis randomised, controlled, open-label platform trial (Randomised Evaluation of COVID-19 Therapy [RECOVERY]), is assessing multiple possible treatments in patients hospitalised for COVID-19. Eligible and consenting patients were randomly allocated (1:1) to either usual standard of care alone (usual care group) or usual care plus baricitinib 4 mg once daily by mouth for 10 days or until discharge if sooner (baricitinib group). The primary outcome was 28-day mortality assessed in the intention-to-treat population. A meta-analysis was conducted that included the results from the RECOVERY trial and all previous randomised controlled trials of baricitinib or other JAK inhibitor in patients hospitalised with COVID-19. The RECOVERY trial is registered with ISRCTN (50189673) and clinicaltrials.gov (NCT04381936). FindingsBetween 2 February 2021 and 29 December 2021, 8156 patients were randomly allocated to receive usual care plus baricitinib versus usual care alone. At randomisation, 95% of patients were receiving corticosteroids and 23% receiving tocilizumab (with planned use within the next 24 hours recorded for a further 9%). Overall, 513 (12%) of 4148 patients allocated to baricitinib versus 546 (14%) of 4008 patients allocated to usual care died within 28 days (age-adjusted rate ratio 0{middle dot}87; 95% CI 0{middle dot}77-0{middle dot}98; p=0{middle dot}026). This 13% proportional reduction in mortality was somewhat smaller than that seen in a meta-analysis of 8 previous trials of a JAK inhibitor (involving 3732 patients and 425 deaths) in which allocation to a JAK inhibitor was associated with a 43% proportional reduction in mortality (rate ratio 0.57; 95% CI 0.45-0.72). Including the results from RECOVERY into an updated meta-analysis of all 9 completed trials (involving 11,888 randomised patients and 1484 deaths) allocation to baricitinib or other JAK inhibitor was associated with a 20% proportional reduction in mortality (rate ratio 0.80; 95% CI 0.71-0.89; p<0.001). In RECOVERY, there was no significant excess in death or infection due to non-COVID-19 causes and no excess of thrombosis, or other safety outcomes. InterpretationIn patients hospitalised for COVID-19, baricitinib significantly reduced the risk of death but the size of benefit was somewhat smaller than that suggested by previous trials. The total randomised evidence to date suggests that JAK inhibitors (chiefly baricitinib) reduce mortality in patients hospitalised for COVID-19 by about one-fifth. FundingUK Research and Innovation (Medical Research Council) and National Institute of Health Research (Grant ref: MC_PC_19056).

5.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-22270447

RESUMO

BackgroundT cell responses to SARS-CoV-2 following infection and vaccination are less characterised than antibody responses, due to a more complex experimental pathway. MethodsWe measured T cell responses in 108 healthcare workers (HCWs) in an observational cohort study, using the commercialised Oxford Immunotec T-SPOT Discovery SARS-CoV-2 assay (OI T-SPOT) and the PITCH ELISpot protocol established for academic research settings. ResultsBoth assays detected T cell responses to SARS-CoV-2 spike, membrane and nucleocapsid proteins. Responses were significantly lower when reported by OI T-SPOT than by PITCH ELISpot. Four weeks after two doses of either Pfizer/BioNTech BNT162b or ChAdOx1 nCoV-19 AZD1222 vaccine, the responder rate was 63% for OI T-SPOT Panels1+2 (peptides representing SARS-CoV-2 spike protein excluding regions present in seasonal coronaviruses), 69% for OI T-SPOT Panel 14 (peptides representing the entire SARS-CoV-2 spike), and 94% for the PITCH ELISpot assay. The two OI T-SPOT panels correlated strongly with each other showing that either readout quantifies spike-specific T cell responses, although the correlation between the OI T-SPOT panels and the PITCH ELISpot was moderate. ConclusionThe standardisation, relative scalability and longer interval between blood acquisition and processing are advantages of the commercial OI T-SPOT assay. However, the OI T-SPOT assay measures T cell responses at a significantly lower magnitude compared to the PITCH ELISpot assay, detecting T cell responses in a lower proportion of vaccinees. This has implications for the reporting of low-level T cell responses that may be observed in patient populations and for the assessment of T cell durability after vaccination.

6.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-21265499

RESUMO

The COVID-19 pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a global crisis with unprecedented challenges for public health. Vaccinations against SARS-CoV-2 have slowed the incidence of new infections and reduced disease severity. As the time-of-day of vaccination has been reported to influence host immune responses to multiple pathogens, we quantified the influence of SARS-CoV-2 vaccination time, vaccine type, age, sex, and days post-vaccination on anti-Spike antibody responses in healthcare workers. The magnitude of the anti-Spike antibody response associated with the time-of-day of vaccination, vaccine type, participant age, sex, and days post vaccination. These results may be relevant for optimizing SARS-CoV-2 vaccine efficacy.

7.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-21259028

RESUMO

BackgroundDespite robust efforts, patients and staff acquire SARS-CoV-2 infection in hospitals. In this retrospective cohort study, we investigated whether whole-genome sequencing (WGS) could enhance the epidemiological investigation of healthcare-associated SARS-CoV-2 acquisition. Methods and findingsFrom 17-November-2020 to 5-January-2021, 803 inpatients and 329 staff were diagnosed with SARS-CoV-2 infection across four teaching hospitals in Oxfordshire, UK. We classified cases according to epidemiological definitions, sought epidemiological evidence of a potential source for each nosocomial infection, and evaluated if epidemiologically-linked cases had genomic evidence supporting transmission. We compared epidemiological and genomic outbreak identification. Using national epidemiological definitions, 109/803 (14%) inpatient infections were classified as definite/probable nosocomial, 615 (77%) as community-acquired and 79 (10%) as indeterminate. There was strong epidemiological evidence to support definite/probable cases as nosocomial: 107/109 (98%) had a prior-negative PCR in the same hospital stay before testing positive, and 101(93%) shared time and space with known infected patients/staff. Many indeterminate cases were likely infected in hospital: 53/79 (67%) had a prior-negative PCR and 75 (95%) contact with a potential source. 89/615 (11% of all 803 patients) with apparent community-onset had a recent hospital exposure. WGS highlighted SARS-CoV-2 is mainly imported into hospitals: within 764 samples sequenced 607 genomic clusters were identified (>1 SNP distinct). Only 43/607 (7%) clusters contained evidence of onward transmission (subsequent cases within [≤]1 SNP). 20/21 epidemiologically-identified outbreaks contained multiple genomic introductions. Most (80%) nosocomial acquisition occurred in rapid super-spreading events in settings with a mix of COVID-19 and non-COVID-19 patients. Hospitals not routinely admitting COVID-19 patients had low rates of transmission. Undiagnosed/unsequenced individuals prevent genomic data from excluding nosocomial acquisition. ConclusionsOur findings suggest current surveillance definitions underestimate nosocomial acquisition and reveal most nosocomial transmission occurs from a relatively limited number of highly infectious individuals.

8.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-21258542

RESUMO

BackgroundREGEN-COV is a combination of 2 monoclonal antibodies (casirivimab and imdevimab) that bind to two different sites on the receptor binding domain of the SARS-CoV-2 spike protein. We aimed to evaluate the efficacy and safety of REGEN-COV in patients admitted to hospital with COVID-19. MethodsIn this randomised, controlled, open-label platform trial, several possible treatments were compared with usual care in patients hospitalised with COVID-19. Eligible and consenting patients were randomly allocated (1:1) to either usual standard of care alone (usual care group) or usual care plus a single dose of REGEN-COV 8g (casirivimab 4g and imdevimab 4g) by intravenous infusion (REGEN-COV group). The primary outcome was 28-day mortality assessed first among patients without detectable antibodies to SARS-CoV-2 at randomisation (seronegative) and then in the overall population. The trial is registered with ISRCTN (50189673) and clinicaltrials.gov (NCT04381936). FindingsBetween 18 September 2020 and 22 May 2021, 9785 patients were randomly allocated to receive usual care plus REGEN-COV or usual care alone, including 3153 (32%) seronegative patients, 5272 (54%) seropositive patients and 1360 (14%) patients with unknown baseline antibody status. In the primary efficacy population of seronegative patients, 396 (24%) of 1633 patients allocated to REGEN-COV and 451 (30%) of 1520 patients allocated to usual care died within 28 days (rate ratio 0{middle dot}80; 95% CI 0{middle dot}70-0{middle dot}91; p=0{middle dot}0010). In an analysis involving all randomised patients (regardless of baseline antibody status), 944 (20%) of 4839 patients allocated to REGEN-COV and 1026 (21%) of 4946 patients allocated to usual care died within 28 days (rate ratio 0{middle dot}94; 95% CI 0{middle dot}86-1{middle dot}03; p=0{middle dot}17). The proportional effect of REGEN-COV on mortality differed significantly between seropositive and seronegative patients (p value for heterogeneity = 0{middle dot}001). InterpretationIn patients hospitalised with COVID-19, the monoclonal antibody combination of casirivimab and imdevimab (REGEN-COV) reduced 28-day mortality among patients who were seronegative at baseline. FundingUK Research and Innovation (Medical Research Council) and National Institute of Health Research (Grant ref: MC_PC_19056).

9.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-21258132

RESUMO

BackgroundAspirin has been proposed as a treatment for COVID-19 on the basis of its antithrombotic properties. MethodsIn this randomised, controlled, open-label platform trial, several possible treatments were compared with usual care in patients hospitalised with COVID-19. Eligible and consenting adults were randomly allocated in a 1:1 ratio to either usual standard of care plus 150mg aspirin once daily until discharge or usual standard of care alone using web-based simple (unstratified) randomisation with allocation concealment. The primary outcome was 28-day mortality. The trial is registered with ISRCTN (50189673) and clinicaltrials.gov (NCT04381936). FindingsBetween 01 November 2020 and 21 March 2021, 7351 patients were randomly allocated to receive aspirin and 7541 patients to receive usual care alone. Overall, 1222 (17%) patients allocated to aspirin and 1299 (17%) patients allocated to usual care died within 28 days (rate ratio 0{middle dot}96; 95% confidence interval [CI] 0{middle dot}89-1{middle dot}04; p=0{middle dot}35). Consistent results were seen in all pre-specified subgroups of patients. Patients allocated to aspirin had a slightly shorter duration of hospitalisation (median 8 vs. 9 days) and a higher proportion were discharged from hospital alive within 28 days (75% vs. 74%; rate ratio 1{middle dot}06; 95% CI 1{middle dot}02-1{middle dot}10; p=0{middle dot}0062). Among those not on invasive mechanical ventilation at baseline, there was no significant difference in the proportion meeting the composite endpoint of invasive mechanical ventilation or death (21% vs. 22%; risk ratio 0{middle dot}96; 95% CI 0{middle dot}90-1{middle dot}03; p=0{middle dot}23). Aspirin use was associated with an absolute reduction in thrombotic events of 0.6% (SE 0.4%) and an absolute increase in major bleeding events of 0.6% (SE 0.2%). InterpretationIn patients hospitalised with COVID-19, aspirin was not associated with reductions in 28-day mortality or in the risk of progressing to invasive mechanical ventilation or death but was associated with a small increase in the rate of being discharged alive within 28 days. FundingUK Research and Innovation (Medical Research Council), National Institute of Health Research (Grant ref: MC_PC_19056), and the Wellcome Trust (Grant Ref: 222406/Z/20/Z) through the COVID-19 Therapeutics Accelerator.

10.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-21257267

RESUMO

BackgroundColchicine has been proposed as a treatment for COVID-19 on the basis of its anti-inflammatory actions. MethodsIn this randomised, controlled, open-label trial, several possible treatments were compared with usual care in patients hospitalised with COVID-19. Eligible and consenting adults were randomly allocated in a 1:1 ratio to either usual standard of care alone or usual standard of care plus colchicine twice daily for 10 days or until discharge (or one of the other treatment arms) using web-based simple (unstratified) randomisation with allocation concealment. The primary outcome was 28-day mortality. The trial is registered with ISRCTN (50189673) and clinicaltrials.gov (NCT04381936). FindingsBetween 27 November 2020 and 4 March 2021, 5610 patients were randomly allocated to receive colchicine and 5730 patients to receive usual care alone. Overall, 1173 (21%) patients allocated to colchicine and 1190 (21%) patients allocated to usual care died within 28 days (rate ratio 1.01; 95% confidence interval [CI] 0.93-1.10; p=0.77). Consistent results were seen in all pre-specified subgroups of patients. There was no significant difference in duration of hospitalisation (median 10 days vs. 10 days) or the proportion of patients discharged from hospital alive within 28 days (70% vs. 70%; rate ratio 0.98; 95% CI 0.94-1.03; p=0.44). Among those not on invasive mechanical ventilation at baseline, there was no significant difference in the proportion meeting the composite endpoint of invasive mechanical ventilation or death (25% vs. 25%; risk ratio 1.02; 95% CI 0.96-1.09; p=0.47). InterpretationIn adults hospitalised with COVID-19, colchicine was not associated with reductions in 28-day mortality, duration of hospital stay, or risk of progressing to invasive mechanical ventilation or death. FundingUK Research and Innovation (Medical Research Council) and National Institute of Health Research (Grant ref: MC_PC_19056). Wellcome Trust (Grant Ref: 222406/Z/20/Z) through the COVID-19 Therapeutics Accelerator.

11.
- The COvid-19 Multi-omics Blood ATlas (COMBAT) Consortium; David J Ahern; Zhichao Ai; Mark Ainsworth; Chris Allan; Alice Allcock; Azim Ansari; Carolina V Arancibia-Carcamo; Dominik Aschenbrenner; Moustafa Attar; J. Kenneth Baillie; Eleanor Barnes; Rachael Bashford-Rogers; Archana Bashyal; Sally Beer; Georgina Berridge; Amy Beveridge; Sagida Bibi; Tihana Bicanic; Luke Blackwell; Paul Bowness; Andrew Brent; Andrew Brown; John Broxholme; David Buck; Katie L Burnham; Helen Byrne; Susana Camara; Ivan Candido Ferreira; Philip Charles; Wentao Chen; Yi-Ling Chen; Amanda Chong; Elizabeth Clutterbuck; Mark Coles; Christopher P Conlon; Richard Cornall; Adam P Cribbs; Fabiola Curion; Emma E Davenport; Neil Davidson; Simon Davis; Calliope Dendrou; Julie Dequaire; Lea Dib; James Docker; Christina Dold; Tao Dong; Damien Downes; Alexander Drakesmith; Susanna J Dunachie; David A Duncan; Chris Eijsbouts; Robert Esnouf; Alexis Espinosa; Rachel Etherington; Benjamin Fairfax; Rory Fairhead; Hai Fang; Shayan Fassih; Sally Felle; Maria Fernandez Mendoza; Ricardo Ferreira; Roman Fischer; Thomas Foord; Aden Forrow; John Frater; Anastasia Fries; Veronica Gallardo Sanchez; Lucy Garner; Clementine Geeves; Dominique Georgiou; Leila Godfrey; Tanya Golubchik; Maria Gomez Vazquez; Angie Green; Hong Harper; Heather A Harrington; Raphael Heilig; Svenja Hester; Jennifer Hill; Charles Hinds; Clare Hird; Ling-Pei Ho; Renee Hoekzema; Benjamin Hollis; Jim Hughes; Paula Hutton; Matthew Jackson; Ashwin Jainarayanan; Anna James-Bott; Kathrin Jansen; Katie Jeffery; Elizabeth Jones; Luke Jostins; Georgina Kerr; David Kim; Paul Klenerman; Julian C Knight; Vinod Kumar; Piyush Kumar Sharma; Prathiba Kurupati; Andrew Kwok; Angela Lee; Aline Linder; Teresa Lockett; Lorne Lonie; Maria Lopopolo; Martyna Lukoseviciute; Jian Luo; Spyridoula Marinou; Brian Marsden; Jose Martinez; Philippa Matthews; Michalina Mazurczyk; Simon McGowan; Stuart McKechnie; Adam Mead; Alexander J Mentzer; Yuxin Mi; Claudia Monaco; Ruddy Montadon; Giorgio Napolitani; Isar Nassiri; Alex Novak; Darragh O'Brien; Daniel O'Connor; Denise O'Donnell; Graham Ogg; Lauren Overend; Inhye Park; Ian Pavord; Yanchun Peng; Frank Penkava; Mariana Pereira Pinho; Elena Perez; Andrew J Pollard; Fiona Powrie; Bethan Psaila; T. Phuong Quan; Emmanouela Repapi; Santiago Revale; Laura Silva-Reyes; Jean-Baptiste Richard; Charlotte Rich-Griffin; Thomas Ritter; Christine S Rollier; Matthew Rowland; Fabian Ruehle; Mariolina Salio; Stephen N Sansom; Alberto Santos Delgado; Tatjana Sauka-Spengler; Ron Schwessinger; Giuseppe Scozzafava; Gavin Screaton; Anna Seigal; Malcolm G Semple; Martin Sergeant; Christina Simoglou Karali; David Sims; Donal Skelly; Hubert Slawinski; Alberto Sobrinodiaz; Nikolaos Sousos; Lizzie Stafford; Lisa Stockdale; Marie Strickland; Otto Sumray; Bo Sun; Chelsea Taylor; Stephen Taylor; Adan Taylor; Supat Thongjuea; Hannah Thraves; John A Todd; Adriana Tomic; Orion Tong; Amy Trebes; Dominik Trzupek; Felicia A Tucci; Lance Turtle; Irina Udalova; Holm Uhlig; Erinke van Grinsven; Iolanda Vendrell; Marije Verheul; Alexandru Voda; Guanlin Wang; Lihui Wang; Dapeng Wang; Peter Watkinson; Robert Watson; Michael Weinberger; Justin Whalley; Lorna Witty; Katherine Wray; Luzheng Xue; Hing Yuen Yeung; Zixi Yin; Rebecca K Young; Jonathan Youngs; Ping Zhang; Yasemin-Xiomara Zurke.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-21256877

RESUMO

Treatment of severe COVID-19 is currently limited by clinical heterogeneity and incomplete understanding of potentially druggable immune mediators of disease. To advance this, we present a comprehensive multi-omic blood atlas in patients with varying COVID-19 severity and compare with influenza, sepsis and healthy volunteers. We identify immune signatures and correlates of host response. Hallmarks of disease severity revealed cells, their inflammatory mediators and networks as potential therapeutic targets, including progenitor cells and specific myeloid and lymphocyte subsets, features of the immune repertoire, acute phase response, metabolism and coagulation. Persisting immune activation involving AP-1/p38MAPK was a specific feature of COVID-19. The plasma proteome enabled sub-phenotyping into patient clusters, predictive of severity and outcome. Tensor and matrix decomposition of the overall dataset revealed feature groupings linked with disease severity and specificity. Our systems-based integrative approach and blood atlas will inform future drug development, clinical trial design and personalised medicine approaches for COVID-19.

12.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-21256245

RESUMO

BackgroundSARS-CoV-2 can spread efficiently in hospitals, but the transmission pathways amongst patients and healthcare workers are unclear. MethodsWe analysed data from four teaching hospitals in Oxfordshire, UK, from January to October 2020. Associations between infectious SARS-CoV-2 individuals and infection risk were quantified using logistic, generalised additive and linear mixed models. Cases were classified as community- or hospital-acquired using likely incubation periods. ResultsNine-hundred and twenty of 66184 patients who were hospitalised during the study period had a positive SARS-CoV-2 PCR test within the same period (1%). Out of these, 571 patients had their first positive PCR tests while hospitalised (62%), and 97 of these occurred at least seven days after admission (11%). Amongst the 5596 healthcare workers, 615 (11%) tested positive during the study period using PCR or serological tests. For susceptible patients, one day in the same ward with another patient with hospital-acquired SARS-CoV-2 was associated with an additional eight infections per 1000 susceptible patients (95%CrI 6-10). Exposure to an infectious patient with community-acquired COVID-19 or to an infectious healthcare worker was associated with substantially lower infection risks (2/1000 susceptible patients/day, 95%CrI 1-2). As for healthcare worker infections, exposure to an infectious patient with hospital-acquired SARS-CoV-2 or to an infectious healthcare worker were both associated with an additional one infection per 1000 susceptible healthcare workers per day (95%CrI 1-2). Exposure to an infectious patient with community-acquired SARS-CoV-2 was associated with half this risk (0.5/1000 susceptible healthcare workers/day, 95%CrI 0.3-0.7). InterpretationExposure to patients with hospital-acquired SARS-CoV-2 poses a substantial infection risk. Infection control measures to limit nosocomial transmission must be optimised to protect both staff and patients from SARS-CoV-2 infection. FundingNational Institute for Health Research Health Protection Research Unit (NIHR HPRU) in Healthcare Associated Infections and Antimicrobial Resistance at Oxford University in partnership with Public Health England (PHE) (NIHR200915). Medical Research Council, Nosocomial transmission of SARS-CoV-2 (MR/V028456/1). Research in contextO_ST_ABSEvidence before this studyC_ST_ABSWe searched the PubMed database using the search terms ("COVID-19" OR "SARS-CoV-2") AND ("nosocomial" OR "hospital") AND ("transmission") in either the abstracts or titles, for English-language articles published up to March 31, 2021. This returned 748 results, out of which ten reported transmission events in the hospital setting quantitatively. These publications can be broadly categorised to epidemiological descriptions of isolated outbreaks (5) or contact tracing of patients exposed to infected healthcare workers (1), retrospective cohort studies involving a particular group of patients, e.g., patients who underwent surgical procedures (2), and using genomic sequencing to identify transmission clusters (2). None of the studies reported the comparative transmission rates of SARS-CoV-2 amongst patients and staff. Added value of this studyThis study reports the analysis of a large observational dataset collected from a group of hospitals in the UK over eight months, consisting of both hospitalised patients and healthcare workers. Based on these detailed individual-level data, we quantified the associations between patient and healthcare worker characteristics and risks for acquiring nosocomial SARS-CoV-2 infection after adjusting for their exposures to SARS-CoV-2. Over the study period, we describe how risk of acquisition changes both with calendar time and over a patients hospital stay. By linking the presence of infected and susceptible patients and healthcare workers by time and ward locations, we quantify the relative importance of the transmission pathways for both the susceptible patients and healthcare workers. Implications of all the available evidenceNosocomial transmission of SARS-CoV-2 is common. Identifying the drivers of SARS-CoV-2 transmissions in the hospital setting is essential for designing infection prevention and control policies to minimise the added pressure from such events on our health systems. We found that newly infected patients who acquired SARS-CoV-2 in the hospital pose the highest risk of onward transmission to other patients and healthcare workers. Infection control and prevention efforts need to be enhanced around these patients to prevent further transmissions and studies assessing the effectiveness of these policies are needed.

13.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-21254061

RESUMO

ObjectivesWe investigate determinants of SARS-CoV-2 anti-spike IgG responses in healthcare workers (HCWs) following one or two doses of Pfizer-BioNTech or Oxford-AstraZeneca vaccines. MethodsHCWs participating in regular SARS-CoV-2 PCR and antibody testing were invited for serological testing prior to first and second vaccination, and 4 weeks post-vaccination if receiving a 12-week dosing interval. Quantitative post-vaccination anti-spike antibody responses were measured using the Abbott SARS-CoV-2 IgG II Quant assay (detection threshold: [≥]50 AU/ml). We used multivariable logistic regression to identify predictors of seropositivity and generalised additive models to track antibody responses over time. ResultsVaccine uptake was 80%, but less in lower-paid roles and Black, south Asian and minority ethnic groups. 3570/3610(98.9%) HCWs were seropositive >14 days post-first vaccination and prior to second vaccination, 2706/2720(99.5%) after Pfizer-BioNTech and 864/890(97.1%) following Oxford-AstraZeneca vaccines. Previously infected and younger HCWs were more likely to test seropositive post-first vaccination, with no evidence of differences by sex or ethnicity. All 470 HCWs tested >14 days after second vaccine were seropositive. Quantitative antibody responses were higher after previous infection: median(IQR) >21 days post-first Pfizer-BioNTech 14,604(7644-22,291) AU/ml vs. 1028(564-1985) AU/ml without prior infection (p<0.001). Oxford-AstraZeneca vaccine recipients had lower readings post-first dose compared to Pfizer-BioNTech, with and without previous infection, 10,095(5354-17,096) and 435(203-962) AU/ml respectively (both p<0.001 vs. Pfizer-BioNTech). Antibody responses post-second vaccination were similar to those after prior infection and one vaccine dose. ConclusionsVaccination leads to detectable anti-spike antibodies in nearly all adult HCWs. Whether differences in response impact vaccine efficacy needs further study.

14.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-21253218

RESUMO

BackgroundNatural and vaccine-induced immunity will play a key role in controlling the SARS-CoV-2 pandemic. SARS-CoV-2 variants have the potential to evade natural and vaccine-induced immunity. MethodsIn a longitudinal cohort study of healthcare workers (HCWs) in Oxfordshire, UK, we investigated the protection from symptomatic and asymptomatic PCR-confirmed SARS-CoV-2 infection conferred by vaccination (Pfizer-BioNTech BNT162b2, Oxford-AstraZeneca ChAdOx1 nCOV-19) and prior infection (determined using anti-spike antibody status), using Poisson regression adjusted for age, sex, temporal changes in incidence and role. We estimated protection conferred after one versus two vaccinations and from infections with the B.1.1.7 variant identified using whole genome sequencing. Results13,109 HCWs participated; 8285 received the Pfizer-BioNTech vaccine (1407 two doses) and 2738 the Oxford-AstraZeneca vaccine (49 two doses). Compared to unvaccinated seronegative HCWs, natural immunity and two vaccination doses provided similar protection against symptomatic infection: no HCW vaccinated twice had symptomatic infection, and incidence was 98% lower in seropositive HCWs (adjusted incidence rate ratio 0.02 [95%CI <0.01-0.18]). Two vaccine doses or seropositivity reduced the incidence of any PCR-positive result with or without symptoms by 90% (0.10 [0.02-0.38]) and 85% (0.15 [0.08-0.26]) respectively. Single-dose vaccination reduced the incidence of symptomatic infection by 67% (0.33 [0.21-0.52]) and any PCR-positive result by 64% (0.36 [0.26-0.50]). There was no evidence of differences in immunity induced by natural infection and vaccination for infections with S-gene target failure and B.1.1.7. ConclusionNatural infection resulting in detectable anti-spike antibodies and two vaccine doses both provide robust protection against SARS-CoV-2 infection, including against the B.1.1.7 variant. SummaryNatural infection resulting in detectable anti-spike antibodies and two vaccine doses both provided [≥] 85% protection against symptomatic and asymptomatic SARS-CoV-2 infection in healthcare workers, including against the B.1.1.7 variant. Single dose vaccination reduced symptomatic infection by 67%.

15.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-21252736

RESUMO

BackgroundTreatment of COVID-19 patients with plasma containing anti-SARS-CoV-2 antibodies may have a beneficial effect on clinical outcomes. We aimed to evaluate the safety and efficacy of convalescent plasma in patients admitted to hospital with COVID-19. MethodsIn this randomised, controlled, open-label, platform trial (Randomised Evaluation of COVID-19 Therapy [RECOVERY]) several possible treatments are being compared with usual care in patients hospitalised with COVID-19 in the UK. Eligible and consenting patients were randomly allocated to receive either usual care plus high titre convalescent plasma or usual care alone. The primary outcome was 28-day mortality. FindingsBetween 28 May 2020 and 15 January 2021, 5795 patients were randomly allocated to receive convalescent plasma and 5763 to usual care alone. There was no significant difference in 28-day mortality between the two groups: 1398 (24%) of 5795 patients allocated convalescent plasma and 1408 (24%) of 5763 patients allocated usual care died within 28 days (rate ratio [RR] 1{middle dot}00; 95% confidence interval [CI] 0{middle dot}93 to 1{middle dot}07; p=0{middle dot}93). The 28-day mortality rate ratio was similar in all prespecified subgroups of patients, including in those patients without detectable SARS-CoV-2 antibodies at randomisation. Allocation to convalescent plasma had no significant effect on the proportion of patients discharged from hospital within 28 days (66% vs. 67%; rate ratio 0{middle dot}98; 95% CI 0{middle dot}94-1{middle dot}03, p=0{middle dot}50). Among those not on invasive mechanical ventilation at baseline, there was no significant difference in the proportion meeting the composite endpoint of progression to invasive mechanical ventilation or death (28% vs. 29%; rate ratio 0{middle dot}99; 95% CI 0{middle dot}93-1{middle dot}05, p=0{middle dot}79). InterpretationAmong patients hospitalised with COVID-19, high-titre convalescent plasma did not improve survival or other prespecified clinical outcomes. FundingUK Research and Innovation (Medical Research Council) and National Institute of Health Research (Grant refs: MC_PC_19056; COV19-RECPLA).

16.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-21249258

RESUMO

Findings: Between 23 April 2020 and 25 January 2021, 4116 adults were included in the assessment of tocilizumab, including 562 (14%) patients receiving invasive mechanical ventilation, 1686 (41%) receiving non-invasive respiratory support, and. 1868 (45%) receiving no respiratory support other than oxygen. Median CRP was 143 [IQR 107-205] mg/L and 3385 (82%) patients were receiving systemic corticosteroids at randomisation. Overall, 596 (29%) of the 2022 patients allocated tocilizumab and 694 (33%) of the 2094 patients allocated to usual care died within 28 days (rate ratio 0.86; 95% confidence interval [CI] 0.77-0.96; p=0.007). Consistent results were seen in all pre-specified subgroups of patients, including those receiving systemic corticosteroids. Patients allocated to tocilizumab were more likely to be discharged from hospital alive within 28 days (54% vs. 47%; rate ratio 1.23; 95% CI 1.12-1.34; p<0.0001). Among those not receiving invasive mechanical ventilation at baseline, patients allocated tocilizumab were less likely to reach the composite endpoint of invasive mechanical ventilation or death (33% vs. 38%; risk ratio 0.85; 95% CI 0.78-0.93; p=0.0005). Interpretation: In hospitalised COVID-19 patients with hypoxia and systemic inflammation, tocilizumab improved survival and other clinical outcomes regardless of the level of respiratory support received and in addition to the use of systemic corticosteroids.

17.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-20245944

RESUMO

BackgroundAzithromycin has been proposed as a treatment for COVID-19 on the basis of its immunomodulatory actions. We evaluated the efficacy and safety of azithromycin in hospitalised patients with COVID-19. MethodsIn this randomised, controlled, open-label, adaptive platform trial, several possible treatments were compared with usual care in patients hospitalised with COVID-19 in the UK. Eligible and consenting patients were randomly allocated to either usual standard of care alone or usual standard of care plus azithromycin 500 mg once daily by mouth or intravenously for 10 days or until discharge (or one of the other treatment arms). Patients were twice as likely to be randomised to usual care as to any of the active treatment groups. The primary outcome was 28-day mortality. The trial is registered with ISRCTN (50189673) and clinicaltrials.gov (NCT04381936). FindingsBetween 7 April and 27 November 2020, 2582 patients were randomly allocated to receive azithromycin and 5182 patients to receive usual care alone. Overall, 496 (19%) patients allocated to azithromycin and 997 (19%) patients allocated to usual care died within 28 days (rate ratio 1{middle dot}00; 95% confidence interval [CI] 0{middle dot}90-1{middle dot}12; p=0{middle dot}99). Consistent results were seen in all pre-specified subgroups of patients. There was no difference in duration of hospitalisation (median 12 days vs. 13 days) or the proportion of patients discharged from hospital alive within 28 days (60% vs. 59%; rate ratio 1{middle dot}03; 95% CI 0{middle dot}97-1{middle dot}10; p=0{middle dot}29). Among those not on invasive mechanical ventilation at baseline, there was no difference in the proportion meeting the composite endpoint of invasive mechanical ventilation or death (21% vs. 22%; risk ratio 0{middle dot}97; 95% CI 0{middle dot}89-1{middle dot}07; p=0{middle dot}54). InterpretationIn patients hospitalised with COVID-19, azithromycin did not provide any clinical benefit. Azithromycin use in patients hospitalised with COVID-19 should be restricted to patients where there is a clear antimicrobial indication. FundingUK Research and Innovation (Medical Research Council) and National Institute of Health Research (Grant ref: MC_PC_19056).

18.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-20234369

RESUMO

BackgroundIt is critical to understand whether infection with Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) protects from subsequent reinfection. MethodsWe investigated the incidence of SARS-CoV-2 PCR-positive results in seropositive and seronegative healthcare workers (HCWs) attending asymptomatic and symptomatic staff testing at Oxford University Hospitals, UK. Baseline antibody status was determined using anti-spike and/or anti-nucleocapsid IgG assays and staff followed for up to 30 weeks. We used Poisson regression to estimate the relative incidence of PCR-positive results and new symptomatic infection by antibody status, accounting for age, gender and changes in incidence over time. ResultsA total of 12219 HCWs participated and had anti-spike IgG measured, 11052 were followed up after negative and 1246 after positive antibody results including 79 who seroconverted during follow up. 89 PCR-confirmed symptomatic infections occurred in seronegative individuals (0.46 cases per 10,000 days at risk) and no symptomatic infections in those with anti-spike antibodies. Additionally, 76 (0.40/10,000 days at risk) anti-spike IgG seronegative individuals had PCR-positive tests in asymptomatic screening, compared to 3 (0.21/10,000 days at risk) seropositive individuals. Overall, positive baseline anti-spike antibodies were associated with lower rates of PCR-positivity (with or without symptoms) (adjusted rate ratio 0.24 [95%CI 0.08-0.76, p=0.015]). Rate ratios were similar using anti-nucleocapsid IgG alone or combined with anti-spike IgG to determine baseline status. ConclusionsPrior SARS-CoV-2 infection that generated antibody responses offered protection from reinfection for most people in the six months following infection. Further work is required to determine the long-term duration and correlates of post-infection immunity.

19.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-20224824

RESUMO

BackgroundSARS-CoV-2 IgG antibody measurements can be used to estimate the proportion of a population exposed or infected and may be informative about the risk of future infection. Previous estimates of the duration of antibody responses vary. MethodsWe present 6 months of data from a longitudinal seroprevalence study of 3217 UK healthcare workers (HCWs). Serial measurements of IgG antibodies to SARS-CoV-2 nucleocapsid were obtained. Bayesian mixed linear models were used to investigate antibody waning and associations with age, gender, ethnicity, previous symptoms and PCR results. ResultsIn this cohort of working age HCWs, antibody levels rose to a peak at 24 (95% credibility interval, CrI 19-31) days post-first positive PCR test, before beginning to fall. Considering 452 IgG seropositive HCWs over a median of 121 days (maximum 171 days) from their maximum positive IgG titre, the mean estimated antibody half-life was 85 (95%CrI, 81-90) days. The estimated mean time to loss of a positive antibody result was 137 (95%CrI 127-148) days. We observed variation between individuals; higher maximum observed IgG titres were associated with longer estimated antibody half-lives. Increasing age, Asian ethnicity and prior self-reported symptoms were independently associated with higher maximum antibody levels, and increasing age and a positive PCR test undertaken for symptoms with longer antibody half-lives. ConclusionIgG antibody levels to SARS-CoV-2 nucleocapsid wane within months, and faster in younger adults and those without symptoms. Ongoing longitudinal studies are required to track the long-term duration of antibody levels and their association with immunity to SARS-CoV-2 reinfection. SummarySerially measured SARS-CoV-2 anti-nucleocapsid IgG titres from 452 seropositive healthcare workers demonstrate levels fall by half in 85 days. From a peak result, detectable antibodies last a mean 137 days. Levels fall faster in younger adults and following asymptomatic infection.

20.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-20174193

RESUMO

3.BackgroundAccess to rapid diagnosis is key to the control and management of SARS-CoV-2. Reverse Transcriptase-Polymerase Chain Reaction (RT-PCR) testing usually requires a centralised laboratory and significant infrastructure. We describe the development and diagnostic accuracy assessment of a novel, rapid point-of-care RT-PCR test, the DnaNudge(R) platform CovidNudge test, which requires no laboratory handling or sample pre-processing. MethodsNasopharyngeal swabs are inserted directly into a cartridge which contains all reagents and components required for RT-PCR reactions, including multiple technical replicates of seven SARS-CoV-2 gene targets (rdrp1, rdrp2, e-gene, n-gene, n1, n2 and n3) and human ribonuclease P (RNaseP) as positive control. Between April and May 2020, swab samples were tested in parallel using the CovidNudge direct-to-cartridge platform and standard laboratory RT-PCR using swabs in viral transport medium. Samples were collected from three groups: self-referred healthcare workers with suspected COVID-19 (Group 1, n=280/386; 73%); patients attending the emergency department with suspected COVID-19 (Group 2, n=15/386; 4%) and hospital inpatient admissions with or without suspected COVID-19 (Group 3, n=91/386; 23%). ResultsOf 386 paired samples tested across all groups, 67 tested positive on the CovidNudge platform and 71 with standard laboratory RT-PCR. The sensitivity of the test varied by group (Group 1 93% [84-98%], Group 2 100% [48-100%] and Group 3 100% [29-100%], giving an average sensitivity of 94.4% (95% confidence interval 86-98%) and an overall specificity of 100% (95%CI 99-100%; Group 1 100% [98-100%]; Group 2 100% [69-100%] and Group 3 100% [96-100%]). Point of care testing performance was comparable during a period of high (25%) and low (3%) background prevalence. Amplification of the viral nucleocapsid (n1, n2, n3) targets were most sensitive for detection of SARS-CoV2, with the assay able to detect 1x104 viral particles in a single swab. ConclusionsThe CovidNudge platform offers a sensitive, specific and rapid point of care test for the presence of SARS-CoV-2 without laboratory handling or sample pre-processing. The implementation of such a device could be used to enable rapid decisions for clinical care and testing programs. 4. RESEARCH IN CONTEXTO_ST_ABSEvidence before this studyC_ST_ABSThe WHO has highlighted the development of rapid, point-of-care diagnostics for detection of SARS-CoV-2 as a key priority to tackle COVID-19. The Foundation for Innovative Diagnostics (FIND) has identified over 90 point-of-care, near patient or mobile tests for viral detection of SARS-CoV-2. However, the most widely available rapid tests to date require some sample handling which limits their use at point-of-care. In addition, pressure on supply chains is restricting access to current diagnostics and alternatives are needed urgently. Added value of this studyWe describe the development and clinical validation of COVID nudge, a novel point-of-care RT-PCR diagnostic, evaluated during the first wave of the SARS-CoV-2 epidemic. The platform is able to achieve high analytic sensitivity and specificity from dry swabs within a self-contained cartridge. The lack of downstream sample handling makes it suitable for use in a range of clinical settings, without need for a laboratory or specialized operator. Multiplexed assays within the cartridge allow inclusion of a positive human control, which reduces the false negative testing rate due to insufficient sampling. Implication of the available evidencePoint-of-care testing can relieve pressure on centralized laboratories and increase overall testing capacity, complementing existing approaches. These findings support a role for COVID Nudge as part of strategies to improve access to rapid diagnostics to SARS-CoV-2. Since May 2020, the system has been implemented in UK hospitals and is being rolled out nationwide.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA