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1.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-22277678

RESUMO

SUMMARYO_ST_ABSBackground & AimsC_ST_ABSVitamin D deficiency has been reported to associate with impaired development of antigen-specific responses following vaccination. We aimed to determine whether vitamin D supplements might boost immunogenicity and efficacy of SARS-CoV-2 vaccination. MethodsWe conducted three sub-studies nested within the CORONAVIT randomised controlled trial, which investigated effects of offering vitamin D supplements at a dose of 800 IU/day or 3200 IU/day vs. no offer on risk of acute respiratory infections, including COVID-19, in UK adults with circulating 25-hydroxyvitamin D concentrations <75 nmol/L. Sub-study 1 (n=2808) investigated effects of vitamin D supplementation on risk of breakthrough SARS-CoV-2 infection following two doses of SARS-CoV-2 vaccine. Sub-study 2 (n=1853) investigated effects of vitamin D supplementation on titres of combined IgG, IgA and IgM (IgGAM) anti-Spike antibodies in eluates of dried blood spots collected after SARS-CoV-2 vaccination. Sub-study 3 (n=100) investigated effects of vitamin D supplementation on neutralising antibody and cellular responses in venous blood samples collected after SARS-CoV-2 vaccination. Results1945/2808 (69.3%) sub-study 1 participants received two doses of ChAdOx1 nCoV-19 (Oxford-AstraZeneca); the remainder received two doses of BNT162b2 (Pfizer). Vitamin D supplementation did not influence risk of breakthrough SARS-CoV-2 infection (800 IU/day vs. no offer: adjusted hazard ratio 1.28, 95% CI 0.89 to 1.84; 3200 IU/day vs. no offer: 1.17, 0.81 to 1.70). Neither did it influence IgGAM anti-Spike titres, neutralising antibody titres or IFN-{gamma} concentrations in supernatants of S peptide-stimulated whole blood. ConclusionsAmong adults with sub-optimal baseline vitamin D status, vitamin D replacement at a dose of 800 or 3200 IU/day did not influence protective efficacy or immunogenicity of SARS-CoV-2 vaccination. Clinical Trial RegistrationClinicalTrials.gov NCT04579640.

2.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-22276205

RESUMO

BackgroundCoronavirus disease 2019 (COVID-19), caused by the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is estimated to have caused more than 18 million deaths worldwide as of end-May 2022. MethodsCOVIDENCE UK is a longitudinal population-based study that investigates risk factors for, and impacts of, COVID-19 in UK residents aged [≥]16 years. A unique feature is the capacity to support trial-within-cohort studies to evaluate interventions for prevention of COVID-19 and other acute respiratory illnesses. Participants complete a detailed online baseline questionnaire capturing self-reported information relating to their socio-demographic characteristics, occupation, lifestyle, quality of life, weight, height, longstanding medical conditions, medication use, vaccination status, diet and supplemental micronutrient intake. Follow-up on-line questionnaires capturing incident symptoms of COVID-19 and other acute respiratory infections, incident swab test-confirmed COVID-19, doses of SARS-CoV-2 vaccine received, and quality of life are completed at monthly intervals. ResultsThe study was launched on 1st May 2020 and closed to recruitment on 6th October 2021. A total of 19,981 participants enrolled and consented to 5-year follow-up with medical record linkage. Their mean age was 59.1 years (range 16.0 to 94.4 years), 70.2% were female, and 93.7% identified their ethnic origin as White. Analyses conducted to date have provided key insights into risk factors for SARS-CoV-2 infection and COVID-19 disease, determinants of SARS-CoV-2 vaccine immunogenicity and efficacy, and impacts of COVID-19 on health economic outcomes. The cohort has also supported conduct of a Phase 3 randomised trial-within-cohort study (CORONAVIT) evaluating implementation of a test-and-treat approach to correcting sub-optimal vitamin D status on incidence and severity of acute respiratory infections, including COVID-19. ConclusionsThe COVIDENCE UK dataset represents a valuable resource containing granular information on factors influencing susceptibility to, and impacts of, COVID-19 in UK adults. Researchers wishing to access anonymised participant-level data should contacting the corresponding author for further information.

3.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-22272276

RESUMO

BackgroundLittle is known about the relative influence of demographic, behavioural, and vaccine-related factors on risk of post-vaccination SARS-CoV-2 infection. We aimed to identify risk factors for SARS-CoV-2 infection after primary and booster vaccinations. MethodsWe undertook a prospective population-based study in UK adults ([≥]16 years) vaccinated against SARS-CoV-2, including data from Jan 12, 2021, to Feb 21, 2022. We modelled risk of post-vaccination SARS-CoV-2 infection separately for participants who had completed a primary course of vaccination (two-dose or, in the immunosuppressed, three-dose course of either ChAdOx1 nCoV-19 [ChAdOx1] or BNT1262b2) and for those who had additionally received a booster dose (BNT1262b2 or mRNA-1273). Cox regression models were used to explore associations between sociodemographic, behavioural, clinical, pharmacological, and nutritional factors and breakthrough infection, defined as a self-reported positive result on a lateral flow or reverse transcription PCR (RT-PCR) test for SARS-CoV-2. Models were further adjusted for weekly SARS-CoV-2 incidence at the local (lower tier local authority) level. Findings14,713 participants were included in the post-primary analysis and 10,665 in the post-booster analysis, with a median follow-up of 203 days (IQR 195-216) in the post-primary cohort and 85 days (66-103) in the post-booster cohort. 1051 (7.1%) participants in the post-primary cohort and 1009 (9.4%) participants in the post-booster cohort reported a breakthrough SARS-CoV-2 infection. A primary course of ChAdOx1 (vs BNT182b2) was associated with higher risk of infection, both in the post-primary cohort (adjusted hazard ratio 1.63, 95% CI 1.41-1.88) and in the post-booster cohort after boosting with mRNA-1273 (1.29 [1.03-1.61] vs BNT162b2 primary plus BNT162b2 booster). A lower risk of breakthrough infection was associated with older age (post-primary: 0.96 [0.96-0.97] per year; post-booster: 0.97 [0.96-0.98]), whereas a higher risk of breakthrough infection was associated with lower levels of education (post-primary: 1.66 [1.35-2.06] for primary or secondary vs postgraduate; post-booster: 1.36 [1.08-1.71]) and at least three weekly visits to indoor public places (post-primary: 1.38 [1.15-1.66] vs none; post-booster: 1.33 [1.10-1.60]). ConclusionsVaccine type, socioeconomic status, age, and behaviours affect risk of breakthrough SARS-CoV-2 infection following a primary schedule and a booster dose. Research in contextO_ST_ABSEvidence before this studyC_ST_ABSWe searched PubMed, medRxiv, and Google Scholar for papers published up to Feb 18, 2022, using the search terms (breakthrough OR post-vaccin*) AND (SARS-CoV-2 OR COVID) AND (disease OR infection) AND (determinant OR "risk factor" OR associat*), with no language restrictions. Existing studies on risk factors for breakthrough SARS-CoV-2 infection among vaccinated individuals have found associations with age, comorbidities, vaccine type, and previous infection; however, findings have been inconsistent across studies. Most studies have been limited to specific subgroups or have focused on severe outcomes, and very few have considered breakthrough infections after a booster dose or have adjusted for behaviours affecting exposure to other people. Added value of this studyThis study is among the first to provide a detailed analysis of a wide range of risk factors for breakthrough SARS-CoV-2 infection, both after the primary course of vaccination and after a booster dose. Our large study size and detailed data have allowed us to investigate associations with various sociodemographic, clinical, pharmacological, and nutritional factors. Monthly follow-up data have additionally given us the opportunity to consider the effects of behaviours that may have changed across the pandemic, while adjusting for local SARS-CoV-2 incidence. Implications of all the available evidenceOur findings add to growing evidence that risk factors for SARS-CoV-2 infection after primary or booster vaccinations can differ to those in unvaccinated populations, with effects attenuated for previously observed risk factors such as body-mass index and Asian ethnicity. The clear difference we observed between the efficacies of ChAdOx1 and BNT162b2 as the primary course of vaccination appears to have been reduced by the use of BNT162b2 boosters, but not by mNRA-1273 boosters. As more countries introduce booster vaccinations, future population-based studies with longer follow-up will be needed to investigate our findings further.

4.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-22270930

RESUMO

BackgroundAntibody responses to SARS-CoV-2 vaccination vary for reasons that remain poorly understood. MethodsWe tested for presence of combined IgG, IgA and IgM (IgGAM) anti-spike antibodies before and after administration of two doses of ChAdOx1 nCoV-19 (ChAdOx1, Oxford-AstraZeneca) or BNT162b2 (Pfizer-BioNTech) in UK adults participating in a population-based longitudinal study who received their first dose of vaccine from December 15, 2020 to July 10, 2021. Information on sixty-six potential sociodemographic, behavioural, clinical, pharmacological and nutritional determinants of serological response to vaccination was captured using serial online questionnaires. We used logistic regression to estimate multivariable-adjusted odds ratios (aORs) for associations between independent variables and risk of seronegativity following two vaccine doses. Participants who were seronegative after receiving two vaccine doses were offered an additional antibody test following subsequent administration of a booster dose of BNT162b2 or mRNA-1273 (Moderna) from September 23 to December 12, 2021. FindingsSerology results following two vaccine doses were available for 9,101 participants, of whom 5,770 (63.4%) received ChAdOx1 and 3,331 (36.6%) received BNT162b2. Anti-spike IgGAM was undetectable in 378 (4.2%) participants at a median of 8.6 weeks (IQR 6.4-10.7 weeks) after their second dose of vaccine. Seronegativity following two doses of SARS-CoV-2 vaccination was associated with administration of ChAdOx1 vs BNT162b2 (aOR 7.03, 95% CI 4.39-11.24), shorter interval between first and second vaccine doses (aOR 2.37, 1.06-5.26, for <6 weeks vs >10 weeks; aOR 1.59, 1.18-2.13, for 6-10 weeks vs >10 weeks), poorer self-assessed general health (aOR 3.33, 1.49-7.46, for poor vs excellent), immunodeficiencies (aOR 6.75, 2.63-17.35) and prescription of systemic immunosuppressants (aOR 3.76, 2.44-5.78). By contrast, pre-vaccination SARS-CoV-2 seropositivity (aOR 0.16, 0.04-0.70, for symptomatic seropositives vs seronegatives) and supplemental vitamin D intake (aOR 0.73, 0.53-0.99) were associated with reduced risk of post-vaccination seronegativity. 247/378 (65.3%) of participants who were seronegative after two doses of ChAdOx1 vs BNT162b2 provided a third sample at a median of 7.8 weeks (IQR 5.8-10.4) after receiving a booster dose of BNT162b2 or mRNA-1273: eight (3.2%) of them remained seronegative after three vaccine doses, all of whom either had a primary immunodeficiency or were taking systemic immunosuppressant drugs. InterpretationWe identify multiple determinants of antibody responses to two doses of ChAdOx1 or BNT162b2, many of which are potentially modifiable. Booster doses of BNT162b2 or mRNA-1273 were highly effective in achieving seroconversion in those who failed to mount antibody responses following two doses of ChAdOx1 or BNT162b2. Study registrationhttps://clinicaltrials.gov/ct2/show/NCT04330599 FundingBarts Charity, Fischer Family Trust, The Exilarchs Foundation, DSM Nutritional Products, Health Data Research UK Research in contextO_ST_ABSEvidence before this studyC_ST_ABSWe searched PubMed, medRxiv, and Google Scholar for papers published from January 1, 2020, to February 1, 2022, using the search terms (antibody OR humoral OR serologic* OR immunogenic*) AND (SARS-CoV-2 vaccine OR ChAdOx1 or BNT162b2 coronavirus), with no language restrictions. Population-based studies investigating multiple potential determinants of vaccine immunogenicity in people with known pre-vaccination SARS-CoV-2 serostatus are lacking. Added value of this studyThis large population-based study, conducted in a population with known pre-vaccination SARS-CoV-2 serostatus, examines a comprehensive range of potential sociodemographic, behavioural, clinical, pharmacological and nutritional determinants of antibody responses to administration of two major SARS-CoV-2 vaccines (i.e., ChAdOx1 or BNT162b2), many of which have not previously been investigated. It is also the first population-based study to characterise antibody responses to booster doses of SARS-CoV-2 vaccines in adults who were seronegative after their primary course of vaccination. Implications of all the available evidenceIncreased risk of seronegativity following two doses of SARS-CoV-2 vaccines was associated with administration of ChAdOx1 vs BNT162b2, shorter interval between first and second vaccine doses, poorer self-assessed general health, immunocompromise and SARS-CoV-2 seronegativity pre-vaccination. Regular intake of vitamin D supplements was associated with reduced risk of post-vaccination seronegativity. Randomised controlled trials are now needed to test for causality. Booster doses of BNT162b2 or mRNA-1273 were highly effective in achieving seroconversion in the majority of people who failed to mount antibody responses following a primary course of vaccination, the few exceptions being a subset of those with primary immunodeficiency or systemic immunosuppressant drugs.

5.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-22270667

RESUMO

In this population-based cohort of 7530 adults, combined IgG/A/M anti-Spike titres measured after SARS-CoV-2 vaccination were predictive of protection against breakthrough SARS-CoV-2 infection. Discrimination was significantly improved by adjustment for factors influencing risk of SARS-CoV-2 exposure including household overcrowding, public transport use, and visits to indoor public places.

6.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-21265767

RESUMO

BackgroundProspective population-based studies investigating multiple determinants of pre-vaccination antibody responses to SARS-CoV-2 are lacking. MethodsWe did a prospective population-based study in SARS-CoV-2 vaccine-naive UK adults recruited between May 1 and November 2, 2020, without a positive swab test result for SARS-CoV-2 prior to enrolment. Information on 88 potential sociodemographic, behavioural, nutritional, clinical and pharmacological risk factors was obtained through online questionnaires, and combined IgG/IgA/IgM responses to SARS-CoV-2 spike glycoprotein were determined in dried blood spots obtained between November 6, 2020 and April 18, 2021. We used logistic and linear regression to estimate adjusted odds ratios (aORs) and adjusted geometric mean ratios (aGMRs) for potential determinants of SARS-CoV-2 seropositivity (all participants) and antibody titres (seropositive participants only), respectively. Results1696 (15.2%) of 11,130 participants were seropositive. Factors independently associated with increased risk of SARS-CoV-2 seropositivity included frontline health/care occupation (aOR 1.86, 95% CI 1.48-2.33), international travel (1.20, 1.07-1.35), number of visits to shops and other indoor public places ([≥]5 vs. 0/week: 1.29, 1.06-1.57, P-trend=0.01), body mass index (BMI) [≥]25 vs <25 kg/m2 (1.24, 1.11-1.39), Asian/Asian British vs White ethnicity (1.65, 1.10-2.49), and alcohol consumption [≥]15 vs 0 units/week (1.23, 1.04-1.46). Light physical exercise associated with decreased risk (0.80, 0.70-0.93, for [≥]10 vs 0-4 h/week). Among seropositive participants, higher titres of anti-Spike antibodies associated with factors including BMI [≥]30 vs <25 kg/m2 (aGMR 1.10, 1.02-1.19), Asian/Asian British vs White ethnicity (1.22, 1.04-1.44), frontline health/care occupation (1.24, 95% CI 1.11-1.39), international travel (1.11, 1.05-1.16), and number of visits to shops and other indoor public places ([≥]5 vs. 0/week: 1.12, 1.02-1.23, P-trend=0.01); these associations were not substantially attenuated by adjustment for COVID-19 disease severity. ConclusionsHigher alcohol consumption and reduced light physical exercise represent new modifiable risk factors for SARS-CoV-2 infection. Recognised associations between Asian/Asian British ethnic origin and obesity and increased risk of SARS-CoV-2 seropositivity were independent of other sociodemographic, behavioural, nutritional, clinical and pharmacological factors investigated. Among seropositive participants, higher titres of anti-Spike antibodies in people of Asian ancestry and in obese people were not explained by greater COVID-19 disease severity in these groups. FundingBarts Charity, Health Data Research UK.

7.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-21254452

RESUMO

BackgroundRisk factors for severe COVID-19 include older age, male sex, obesity, Black or Asian ethnicity and underlying medical conditions. Whether these factors also influence susceptibility to developing COVID-19 is uncertain. MethodsWe undertook a prospective, population-based cohort study (COVIDENCE UK) from 1st May 2020 to 5th February 2021. Baseline information on potential risk factors was captured by online questionnaire. Monthly follow-up questionnaires captured incident COVID-19. We used logistic regression models to estimate multivariable-adjusted odds ratios (aORs) for associations between potential risk factors and risk of COVID-19. FindingsWe recorded 446 incident cases of COVID-19 in 15,227 participants (2.9%). Increased risk of developing COVID-19 was independently associated with Asian/Asian British vs. White ethnicity (aOR 2.31, 95% CI 1.35-3.95), household overcrowding (aOR per additional 0.5 people/bedroom 1.26, 1.11-1.43), any vs. no visits to/from other households in previous week (aOR 1.33, 1.07-1.64), number of visits to indoor public places (aOR per extra visit per week 1.05, 1.01-1.09), frontline occupation excluding health/social care vs. no frontline occupation (aOR 1.49, 1.12-1.98), and raised body mass index (BMI) (aOR 1.51 [1.20-1.90] for BMI 25.0-30.0 kg/m2 and 1.38 [1.05-1.82] for BMI >30.0 kg/m2 vs. BMI <25.0 kg/m2). Atopic disease was independently associated with decreased risk (aOR 0.76, 0.59-0.98). No independent associations were seen for age, sex, other medical conditions, diet, or micronutrient supplement use. InterpretationAfter rigorous adjustment for factors influencing exposure to SARS-CoV-2, Asian/Asian British ethnicity and raised BMI were associated with increased risk of developing COVID-19, while atopic disease was associated with decreased risk. FundingBarts Charity, Health Data Research UK

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