Objective To estimate the real world effectiveness of the Pfizer-BioNTech BNT162b2 and Oxford-AstraZeneca ChAdOx1-S vaccines against confirmed covid-19 symptoms (including the UK variant of concern B.1.1.7), admissions to hospital, and deaths. Design Test negative case-control study. Setting Community testing for covid-19 in England. Participants 156 930 adults aged 70 years and older who reported symptoms of covid-19 between 8 December 2020 and 19 February 2021 and were successfully linked to vaccination data in the National Immunisation Management System. Interventions Vaccination with BNT162b2 or ChAdOx1-S. Main outcome measures Primary outcomes were polymerase chain reaction confirmed symptomatic SARS-CoV-2 infections, admissions to hospital for covid-19, and deaths with covid-19. Results Participants aged 80 years and older vaccinated with BNT162b2 before 4 January 2021 had a higher odds of testing positive for covid-19 in the first nine days after vaccination (odds ratio up to 1.48, 95% confidence interval 1.23 to 1.77), indicating that those initially targeted had a higher underlying risk of infection. Vaccine effectiveness was therefore compared with the baseline post-vaccination period. Vaccine effects were noted 10 to 13 days after vaccination, reaching a vaccine effectiveness of 70% (95% confidence interval 59% to 78%), then plateauing. From 14 days after the second dose a vaccination effectiveness of 89% (85% to 93%) was found compared with the increased baseline risk. Participants aged 70 years and older vaccinated from 4 January (when ChAdOx1-S delivery commenced) had a similar underlying risk of covid-19 to unvaccinated individuals. With BNT162b2, vaccine effectiveness reached 61% (51% to 69%) from 28 to 34 days after vaccination, then plateaued. With ChAdOx1-S, effects were seen from 14 to 20 days after vaccination, reaching an effectiveness of 60% (41% to 73%) from 28 to 34 days, increasing to 73% (27% to 90%) from day 35 onwards. On top of the protection against symptomatic disease, a further 43% (33% to 52%) reduced risk of emergency hospital admission and 51% (37% to 62%) reduced risk of death was observed in those who had received one dose of BNT162b2. Participants who had received one dose of ChAdOx1-S had a further 37% (3% to 59%) reduced risk of emergency hospital admission. Follow-up was insufficient to assess the effect of ChAdOx1-S on mortality. Combined with the effect against symptomatic disease, a single dose of either vaccine was about 80% effective at preventing admission to hospital with covid-19 and a single dose of BNT162b2 was 85% effective at preventing death with covid-19. Conclusion Vaccination with either one dose of BNT162b2 or ChAdOx1-S was associated with a significant reduction in symptomatic covid-19 in older adults, and with further protection against severe disease. Both vaccines showed similar effects. Protection was maintained for the duration of follow-up (>6 weeks). A second dose of BNT162b2 was associated with further protection against symptomatic disease. A clear effect of the vaccines against the B.1.1.7 variant was found.

Background There are few primary care studies of the COVID-19 pandemic. We aimed to identify demographic and clinical risk factors for testing positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) within the Oxford Royal College of General Practitioners (RCGP) Research and Surveillance Centre primary care network. MethodsWe analysed routinely collected, pseudonymised data for patients in the RCGP Research and Surveillance Centre primary care sentinel network who were tested for SARS-CoV-2 between Jan 28 and April 4, 2020. We used multivariable logistic regression models with multiple imputation to identify risk factors for positive SARS-CoV-2 tests within this surveillance network. Findings We identified 3802 SARS-CoV-2 test results, of which 587 were positive. In multivariable analysis, male sex was independently associated with testing positive for SARS-CoV-2 (296 [18•4%] of 1612 men vs 291 [13•3%] of 2190 women; adjusted odds ratio [OR] 1•55, 95% CI 1•27-1•89). Adults were at increased risk of testing positive for SARS-CoV-2 compared with children, and people aged 40-64 years were at greatest risk in the multivariable model (243 [18•5%] of 1316 adults aged 40-64 years vs 23 [4•6%] of 499 children; adjusted OR 5•36, 95% CI 3•28-8•76). Compared with white people, the adjusted odds of a positive test were greater in black people (388 [15•5%] of 2497 white people vs 36 [62•1%] of 58 black people; adjusted OR 4•75, 95% CI 2•65-8•51). People living in urban areas versus rural areas (476 [26•2%] of 1816 in urban areas vs 111 [5•6%] of 1986 in rural areas; adjusted OR 4•59, 95% CI 3•57-5•90) and in more deprived areas (197 [29•5%] of 668 in most deprived vs 143 [7•7%] of 1855 in least deprived; adjusted OR 2•03, 95% CI 1•51-2•71) were more likely to test positive. People with chronic kidney disease were more likely to test positive in the adjusted analysis (68 [32•9%] of 207 with chronic kidney disease vs 519 [14•4%] of 3595 without; adjusted OR 1•91, 95% CI 1•31-2•78), but there was no significant association with other chronic conditions in that analysis. We found increased odds of a positive test among people who are obese (142 [20•9%] of 680 people with obesity vs 171 [13•2%] of 1296 normal-weight people; adjusted OR 1•41, 95% CI 1•04-1•91). Notably, active smoking was linked with decreased odds of a positive test result (47 [11•4%] of 413 active smokers vs 201 [17•9%] of 1125 non-smokers; adjusted OR 0•49, 95% CI 0•34-0•71). Interpretation A positive SARS-CoV-2 test result in this primary care cohort was associated with similar risk factors as observed for severe outcomes of COVID-19 in hospital settings, except for smoking. We provide evidence of potential sociodemographic factors associated with a positive test, including deprivation, population density, ethnicity, and chronic kidney disease. Funding Wellcome Trust.

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Public Health England funds national surveillance of invasive pneumococcal disease.