The effectiveness of COVID-19 vaccination in preventing new severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections in the general community is still unclear. Here, we used the Office for National Statistics COVID-19 Infection Survey—a large community-based survey of individuals living in randomly selected private households across the United Kingdom—to assess the effectiveness of the BNT162b2 (Pfizer–BioNTech) and ChAdOx1 nCoV-19 (Oxford–AstraZeneca; ChAdOx1) vaccines against any new SARS-CoV-2 PCR-positive tests, split according to self-reported symptoms, cycle threshold value (<30 versus ≥30; as a surrogate for viral load) and gene positivity pattern (compatible with B.1.1.7 or not). Using 1,945,071 real-time PCR results from nose and throat swabs taken from 383,812 participants between 1 December 2020 and 8 May 2021, we found that vaccination with the ChAdOx1 or BNT162b2 vaccines already reduced SARS-CoV-2 infections ≥21 d after the first dose (61% (95% confidence interval (CI) = 54–68%) versus 66% (95% CI = 60–71%), respectively), with greater reductions observed after a second dose (79% (95% CI = 65–88%) versus 80% (95% CI = 73–85%), respectively). The largest reductions were observed for symptomatic infections and/or infections with a higher viral burden. Overall, COVID-19 vaccination reduced the number of new SARS-CoV-2 infections, with the largest benefit received after two vaccinations and against symptomatic and high viral burden infections, and with no evidence of a difference between the BNT162b2 and ChAdOx1 vaccines. Results from the Office of National Statistics COVID-19 Infection Survey in the United Kingdom demonstrate that the ChAdOx1 nCoV-19 and BNT162b2 vaccines reduce the incidence of new SARS-CoV-2 infections by up to 65% with a single dose and up to 80% after two doses, with no significant differences in efficacy observed between the two vaccines.
【저자키워드】 viral infection, Epidemiology, Outcomes research, 【초록키워드】 COVID-19, SARS-CoV-2, Efficacy, Vaccine, BNT162b2 vaccine, coronavirus, vaccination, Vaccines, SARS-COV-2 infection, Infection, BNT162b2, infections, COVID-19 vaccination, Real-time PCR, Viral load, B.1.1.7, symptomatic, Statistics, Effectiveness, Community, Swab, incidence, United Kingdom, ChAdOx1, ChAdOx1 nCoV-19, single dose, symptomatic infection, Evidence, Cycle threshold value, nose and throat, reduction, Self-reported symptoms, acute respiratory syndrome, no significant difference, 95% confidence interval, second dose, first dose, individual, PCR-positive, participant, doses, viral burden, office, Pfizer–BioNTech, ChAdOx1 vaccines, COVID-19 Infection Survey, benefit, Randomly, new SARS-CoV-2, Result, greater, selected, reduced, reduce, 【제목키워드】 vaccination, Infection, Impact, United Kingdom, new SARS-CoV-2,