https://www.ox.ac.uk/news/2021-02-02-oxford-coronavirus-vaccine-shows-sustained-protection-76-during-3-month-interval * Skip to main content Home Home * Admissions + Undergraduate + Graduate + Continuing education * Research + Divisions + Research impact + Libraries + Innovation and Partnership + Support for researchers + Research in conversation + Public Engagement with Research * News & Events + Events + Science Blog + Arts Blog + Oxford and coronavirus + Oxford and Brexit + News releases for journalists + Filming in Oxford + Find An Expert * About + Organisation + Facts and figures + Oxford people + Oxford Access + International Oxford + Building Our Future + Jobs + Niu Jin Da Xue Search [ ] [Search] News & Events * Events + Regular events in the University Year + Women Making History: Centenary Events + University Events Office * Science Blog * Arts Blog * Oxford and coronavirus * Oxford and Brexit * News releases for journalists * Filming in Oxford * Find An Expert Photo | Researcher working on vaccine in the lab Photo | Researcher working on vaccine in the lab Published 2 Feb 2021 Share This Tweet Share on Facebook Share on LinkedIn Share on Reddit HomeNewsOxford coronavirus vaccine shows sustained protection of 76% during the 3-month interval until the second dose Oxford coronavirus vaccine shows sustained protection of 76% during the 3-month interval until the second dose ResearchCoronavirusCOVID-19 vaccine * Analyses reveal single standard dose efficacy from day 22 to day 90 post vaccination of 76% with protection not falling in this three-month period * After the second dose vaccine efficacy from two standard doses is 82.4% with the 3-month interval being used in the UK. (82.4% effective, with a 95% confidence interval of 62.7% - 91.7% at 12+ weeks) * Data supports the 4-12 week prime-boost dosing interval recommended by many global regulators * Analyses of PCR positive swabs in UK population suggests vaccine may have substantial effect on transmission of the virus with 67% reduction in positive swabs among those vaccinated Our vaccine work is progressing quickly. To ensure you have the latest information or to find out more about the trial, please visit the Oxford COVID-19 vaccine web hub or visit the COVID-19 trial website. Researchers at the University of Oxford have today published in Preprints with The Lancet an analysis of further data from the ongoing trials of the vaccine. In this, they reveal that the vaccine efficacy is higher at longer prime-boost intervals, and that a single dose of the vaccine is 76% effective from 22- to up to 90-days post vaccination. In this preprint, which is currently under review at The Lancet, they report on an analysis of additional data to include information from the trial up to the 7^th December 2020, which includes a further 201 cases of primary symptomatic COVID-19 (332 cases from 131 reported in previously), They report that the effect of dosing interval on efficacy is pronounced, with vaccine efficacy rising from 54.9% with an interval of less than six weeks to 82.4% when spaced 12 or more weeks apart. They also detail that a single standard dose of the vaccine is 76% effective at protecting from primary symptomatic COVID-19 for the first 90 days post vaccination, once the immune system has built this protection 22 days after the vaccination, with the protection showing little evidence of waning in this period. Professor Andrew Pollard, Chief Investigator of the Oxford Vaccine Trial, and co-author, said: 'These new data provide an important verification of the interim data that was used by more than 25 regulators including the MHRA and EMA to grant the vaccine emergency use authorisation. 'It also supports the policy recommendation made by the Joint Committee on Vaccination and Immunisation (JCVI) for a 12-week prime-boost interval, as they look for the optimal approach to roll out, and reassures us that people are protected from 22 days after a single dose of the vaccine.' The exploratory analyses presented in this preprint suggest that it is the dosing interval and not the dosing level which has a great impact on the efficacy of the vaccine. This is in line with previous research supporting greater efficacy with longer prime-boost intervals done with other vaccines such as influenza, Ebola and malaria. The authors also report further on the potential for the vaccine to reduce transmission of the virus, based on swabs obtained from volunteers in the UK arms of the trial with a 67% reduction after the first dose of the vaccine. They also hope to report data regarding the new variants in the coming days, and expect the findings to be broadly similar to those already reported by fellow vaccine developers. Subscribe to News Latest * active mobility significantly lower carbon footprints, even in urban European contexts with a high incidence of walking and cycling Get on your bike: Active transport makes a significant impact on carbon emissions 2 Feb 2021 * Photo | Researcher working on vaccine in the labOxford coronavirus vaccine shows sustained protection of 76% during the 3-month interval until the second dose 2 Feb 2021 * a wide-range of well-designed NbS can deliver multiple benefits for people and nature. For example, coastal mangroves or coral reefs can protect from storm surges, urban green spaces help to cool cities, and improving soil health can help farmers adapt to Getting the message right on nature-based solutions to climate change 1 Feb 2021 * Photo | Nurse reaching for a ChAdOx1 vaccine vialEuropean Medicines Agency recommends conditional marketing authorisation to ChAdOx1 coronavirus vaccine 29 Jan 2021 * An estimated 62,750 excess deaths resulted in 2020 during the COVID-19 pandemic in England and Wales63,000 extra deaths and a year off life expectancy: COVID in 2020 in England & Wales 27 Jan 2021 FURTHER INFORMATION * Oxford COVID-19 Vaccine web hub * Oxford Vaccine Trial * Jenner Institute * Oxford Vaccine Group All news Share This Tweet Share on Facebook Share on LinkedIn Share on Reddit Connect with us * iTunes * Youtube * Facebook * Twitter * LinkedIn * Weibo * Instagram * Medium * The Conversation Information About * Oxford University * Strategic plan * Oxford's research * Course fees and funding * Libraries * Museums and collections * Open days * Oxford glossary * Freedom of speech statement * Statement on Modern Slavery * Data privacy / GDPR * Sport at Oxford * Conferences at Oxford * Niu Jin Da Xue Information For * Prospective undergraduates * Prospective graduate students * Prospective Continuing Education students * Prospective online/distance learning students * Current Oxford students * Current Oxford staff * Oxford residents/Community * Visitors/Tourists * Media * Alumni * Teachers * Parliamentarians * Businesses/Partnerships Quick Links * Contact search * Jobs and vacancies * Term dates * Map * Nexus365 email * Giving to Oxford * Oxford University Images * (c) University of Oxford 2021 * Contact us * About this site * Legal * Privacy policy * Cookie statement * Accessibility Statement *