ABSTRACT
BackgroundThe imposition of restrictions on social mixing early in the COVID-19 pandemic was followed by a reduction in asthma exacerbations in multiple settings internationally. Temporal trends in social mixing, incident acute respiratory infections (ARI) and asthma exacerbations following relaxation of COVID-19 restrictions have not yet been described. MethodsWe conducted a population-based longitudinal study in 2,312 UK adults with asthma between November 2020 and April 2022. Details of face covering use, social mixing, incident ARI and moderate/severe asthma exacerbations were collected via monthly on-line questionnaires. Temporal changes in these parameters were visualised using Poisson generalised additive models. Multilevel logistic regression was used to test for associations between incident ARI and risk of asthma exacerbations, adjusting for potential confounders. ResultsRelaxation of COVID-19 restrictions from April 2021 coincided with reduced face covering use (p<0.001), increased frequency of indoor visits to public places and other households (p<0.001) and rising incidence of COVID-19 (p<0.001), non-COVID-19 ARI (p<0.001) and moderate/severe asthma exacerbations (p=0.007). Incident non-COVID-19 ARI associated independently with increased risk of asthma exacerbation (adjusted odds ratio 5.75, 95% CI 4.75 to 6.97) as did incident COVID-19, both prior to emergence of the omicron variant of SARS-CoV-2 (5.89, 3.45 to 10.04) and subsequently (5.69, 3.89 to 8.31). ConclusionsRelaxation of COVID-19 restrictions coincided with decreased face covering use, increased social mixing and a rebound in ARI and asthma exacerbations. Associations between incident ARI and risk of moderate/severe asthma exacerbation were similar for non-COVID-19 ARI and COVID-19, both before and after emergence of the SARS-CoV-2 omicron variant. FundingBarts Charity, UKRI
Subject(s)
COVID-19 , Respiratory Tract Infections , AsthmaABSTRACT
Background: Coronavirus 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. Methods: COVIDENCE 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. Results: The 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. Conclusions: The 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.
Subject(s)
COVID-19 , Coronavirus Infections , Respiratory Tract InfectionsABSTRACT
Prospective population-based studies investigating associations between reactive symptoms following SARS-CoV-2 vaccination and serologic responses to vaccination are lacking. We therefore conducted such a study in 9003 adults from the United Kingdom (UK) general population receiving SARS-COV-2 vaccines as part of the national vaccination programme. Data relating to incidence and type of reactive symptoms after vaccination were captured using online questionnaires, along with information on 56 potential determinants of symptom risk. Titres of combined IgG/IgA/IgM responses to SARS-CoV-2 spike (S) glycoprotein were determined in eluates of dried blood spots collected from all participants before and after vaccination. 4262 (47.3%) participants experienced systemic reactive symptoms after a first vaccine dose. Factors associating with lower risk of such symptoms included older age (aOR per additional 10 years of age 0.85, 95% CI 0.81–0.90), male vs. female sex (aOR 0.59, 95% CI 0.53–0.65) and receipt of an mRNA vaccine vs. ChAdOx1 nCoV-19 (0.29, 0.26–0.32 for BNT162b2; 0.06, 0.01–0.26 for mRNA-1273). Higher risk of such symptoms was associated with a history of symptomatic SARS-CoV-2 infection prior to vaccination (2.23, 1.78–2.81) and presence vs. absence of self-rated anxiety or depression at cohort enrolment (1.24, 1.12–1.39). Post-vaccination anti-S titres were higher among participants who experienced reactive symptoms after vaccination vs. those who did not (P < 0.001). We conclude that factors influencing risk of systemic symptoms after SARS-CoV-2 vaccination include demographic characteristics, pre-vaccination SARS-CoV-2 serostatus and vaccine type. Participants experiencing reactive symptoms following SARS-CoV-2 vaccination had higher post-vaccination titres of IgG/A/M anti-S antibodies. Improved public understanding of the frequency of reactogenic symptoms and their positive association with vaccine immunogenicity could potentially increase vaccine uptake.
Subject(s)
COVID-19ABSTRACT
BACKGROUND: Vitamin D metabolites support innate immune responses to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and other respiratory pathogens. Randomized controlled trials of vitamin D to prevent coronavirus disease 2019 (Covid-19) have not yet reported. METHODS: We randomly assigned 6200 U.K. adults to receive an offer of a postal finger-prick 25-hydroxyvitamin D (25[OH]D) test with provision of a 6-month supply of higher-dose vitamin D (3200 IU/d, n=1550) or lower-dose vitamin D (800 IU/d, n=1550) to those with blood 25(OH)D concentration <75 nmol/L, vs. no offer of testing or supplementation (n=3100). The primary outcome was the proportion of participants experiencing at least one swab test- or doctor-confirmed acute respiratory infection (ARI) of any cause at six months. Secondary outcomes included incidence of swab test-confirmed Covid-19. RESULTS: Of 3100 participants offered testing, 2958 (95.4%) accepted, and 2690 (86.8%) had 25(OH)D <75 nmol/L and were sent vitamin D supplements (1356 higher-dose, 1334 lower-dose). 76 (5.0%) vs. 87 (5.7%) vs. 136 (4.6%) participants in higher-dose vs. lower-dose vs. no-offer groups experienced at least one ARI of any cause (odds ratio [OR] for higher-dose vs. no-offer 1.09, 95% CI 0.82-1.46; lower-dose vs. no-offer 1.26, 0.96-1.66). 45 (3.0%) vs. 55 (3.6%) vs. 78 (2.6%) participants in higher-dose vs. lower-dose vs. no-offer groups developed Covid-19 (OR for higher-dose vs. no-offer 1.13, 0.78-1.63; lower-dose vs. no-offer 1.39, 0.98-1.97). CONCLUSIONS: Among adults with a high baseline prevalence of vitamin D insufficiency, implementation of a test-and-treat approach to vitamin D replacement did not reduce risk of all-cause ARI or Covid-19.
Subject(s)
Coronavirus Infections , Severe Acute Respiratory Syndrome , Addison Disease , Respiratory Tract Infections , COVID-19ABSTRACT
Background: Little 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. Methods: We 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. Findings: 14,713 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]). Conclusions: Vaccine type, socioeconomic status, age, and behaviours affect risk of breakthrough SARS-CoV-2 infection following a primary schedule and a booster dose.
Subject(s)
COVID-19 , Breakthrough PainABSTRACT
Summary Background Antibody responses to SARS-CoV-2 vaccination vary for reasons that remain poorly understood. Methods We 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. Findings Serology 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. Interpretation We 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 registration https://clinicaltrials.gov/ct2/show/NCT04330599 Funding Barts Charity, Fischer Family Trust, The Exilarch’s Foundation, DSM Nutritional Products, Health Data Research UK Research in context Evidence before this study We 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 study This 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 evidence Increased 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.
Subject(s)
Immunologic Deficiency SyndromesABSTRACT
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.
Subject(s)
COVID-19ABSTRACT
Background: Prospective population-based studies investigating multiple determinants of pre-vaccination antibody responses to SARS-CoV-2 are lacking. Methods: We did a prospective population-based study in SARS-CoV-2 vaccine-naive UK adults between May 1 and Nov 2, 2020. Information on 88 potential 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. 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. Results: 1696 (15.2%) of 11,130 participants were seropositive. Factors independently associated with increased risk included frontline health/care occupation (aOR 1.86, 95% CI 1.49-2.33), international travel (1.22, 1.08-1.37), BMI >30 vs <25 kg/m2 (1.22, 1.05-1.42), Asian/Asian British vs White ethnicity (1.65, 1.10-2.47), and alcohol consumption [≥]15 vs 0 units/week (1.26, 1.06-1.49). Light physical exercise associated with decreased risk (0.80, 0.69-0.93, for [≥]10 vs 0-4 h/week). Higher titres associated with frontline health/care occupation (aGMR 1.26, 95% CI 1.13-1.41), international travel (1.10, 1.04-1.16), BMI >30 vs <25 kg/m2 (1.09, 1.01-1.17), and Asian/Asian British vs White ethnicity (1.23, 1.03-1.46); these associations were not substantially attenuated by adjustment for disease severity. Conclusions: Higher alcohol consumption and reduced 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, clinical, or behavioural factors investigated.
Subject(s)
Obesity , COVID-19ABSTRACT
Background: Prospective population-based studies investigating multiple determinants of pre-vaccination antibody responses to SARS-CoV-2 are lacking.Methods: We did a prospective population-based study in SARS-CoV-2 vaccine-naive UK adults between May 1 and Nov 2, 2020. Information on 88 potential 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. 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.Findings: 1696 (15.2%) of 11,130 participants were seropositive. Factors independently associated with increased risk included frontline health/care occupation (aOR 1.86, 95% CI 1.49–2.33), international travel (1.22, 1.08–1.37), BMI >30 vs <25 kg/m² (1.22, 1.05–1.42), Asian/Asian British vs White ethnicity (1.65, 1.10–2.47), and alcohol consumption ≥15 vs 0 units/week (1.26, 1.06–1.49). Light physical exercise associated with decreased risk (0.80, 0.69–0.93, for ≥10 vs 0–4 h/week). Higher titres associated with frontline health/care occupation (aGMR 1.26, 95% CI 1.13–1.41), international travel (1.10, 1.04–1.16), BMI >30 vs <25 kg/m² (1.09, 1.01–1.17), and Asian/Asian British vs White ethnicity (1.23, 1.03–1.46); these associations were not substantially attenuated by adjustment for disease severity.Interpretation: Higher alcohol consumption and reduced 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, clinical, or behavioural factors investigated.Funding: Barts Charity, Health Data Research UK.Declaration of Interest: JS declares receipt of payments from Reach plc for news stories written about recruitment to, and findings of, the COVIDENCE UK study. AS is a member of the Scottish Government Chief Medical Officer’s COVID-19 Advisory Group and its Standing Committee on Pandemics. He is also a member of the UK Government’s NERVTAG’s Risk Stratification Subgroup. ARM declares receipt of funding in the last 36 months to support vitamin D research from the following companies who manufacture or sell vitamin D supplements: Pharma Nord Ltd, DSM Nutritional Products Ltd, Thornton & Ross Ltd, Cytoplan Ltd and Hyphens Pharma Ltd. ARM also declares support for attending meetings from the following companies who manufacture or sell vitamin D supplements: Pharma Nord Ltd and Abiogen Pharma Ltd. ARM also declares participation on the Data and Safety Monitoring Board for the Chair, DSMB, VITALITY trial (Vitamin D for Adolescents with HIV to reduce musculoskeletal morbidity and immunopathology). ARM also declares unpaid work as a Programme Committee member for the Vitamin D Workshop. ARM also declares receipt of vitamin D capsules for clinical trial use from Pharma Nord Ltd, Synergy Biologics Ltd and Cytoplan Ltd.Ethical Approval: COVIDENCE UK was sponsored by Queen Mary University of London and approved by Leicester South Research Ethics Committee (ref 20/EM/0117). It is registered withClinicalTrials.gov (NCT04330599).
Subject(s)
HIV Infections , Alcoholism , COVID-19 , HIV Seropositivity , ObesityABSTRACT
Background: The COVID-19 pandemic is a novel population-level stressor. As such, it is important to examine pandemic-related changes in mental health and to identify which individuals are at greatest risk of worsening symptoms. Methods: Online questionnaires were administered to 34,465 individuals in the UK, recruited from existing cohorts or via social media. Around one third (n = 12,718) with prior diagnoses of depression or anxiety completed pre-pandemic mental health assessments, allowing prospective investigation of symptom change. We examined changes in depression, anxiety and PTSD symptoms using prospective, retrospective and global ratings of change assessments. We also examined the effect of key risk factors on changes in symptoms.Outcomes: Prospective analyses showed small decreases in depression (PHQ-9: - .43 points) and anxiety symptoms (GAD-7: -.33 points), and increases in PTSD symptoms (PCL-6: .22 points). Conversely, retrospective analyses demonstrated large significant increases in depression (2.40 points) and anxiety symptoms (1.97 points) and 55% reported worsening mental health since the beginning of the pandemic on a global change rating. Using both prospective and retrospective symptom measures, regression analyses demonstrated that worsening depression, anxiety and PTSD symptoms were associated with i) prior mental health diagnoses, ii) female gender; iii) young age, and iv) unemployed or student status.Interpretation: We highlight the effect of prior mental health diagnoses on worsening mental health during the pandemic and confirm previously-reported sociodemographic risk factors. Discrepancies between prospective and retrospective measures of changes in mental health may be related to recall bias underestimating prior symptom severity.
Subject(s)
Anxiety Disorders , Intellectual Disability , COVID-19 , Stress Disorders, Post-TraumaticABSTRACT
Background: Risk 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. Methods: We undertook a prospective, population-based cohort study (COVIDENCE UK) from 1 st May 2020 to 5 th February 2021 . Baseline information on potential risk factors was captured by an 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. Findings: We 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/m 2 and 1.38 [1.05-1.82] for BMI >30.0 kg/m 2 vs. BMI <25.0 kg/m 2 ). 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. Interpretation: After 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. Trial Registration: It is registered with ClinicalTrials.gov (NCT04330599). Funding: Barts Charity, Health Data Research UK Declaration of Interest: None to declare. Ethical Approval: The study was sponsored by Queen Mary University of London and approved by<br>Leicester South Research Ethics Committee (ref 20/EM/0117).
Subject(s)
COVID-19 , Obesity , Dermatitis, AtopicABSTRACT
Summary Background Risk 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. Methods We undertook a prospective, population-based cohort study (COVIDENCE UK) from 1 st May 2020 to 5 th February 2021. Baseline information on potential risk factors was captured by an 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. Findings We 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/m 2 and 1.38 [1.05-1.82] for BMI >30.0 kg/m 2 vs . BMI <25.0 kg/m 2 ). 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. Interpretation After 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. Funding Barts Charity, Health Data Research UK