Infections of SARS-CoV-2 fell by 65% after a first dose of the Oxford-AstraZeneca or Pfizer-BioNTech vaccines, preliminary results from a large UK surveillance study indicate.
Reductions increased to 70% after a second dose of the Pfizer vaccine, data from the UK Covid-19 Infection Survey show. Not enough people had yet received two doses of the AstraZeneca vaccine to assess this.
The survey, carried out by the University of Oxford in partnership with the Office for National Statistics and the Department of Health and Social Care for England, included data from 1.7 million self-reported swab test results taken from 370 000 UK adults between 1 December 2020 and 3 April 2021.
The results, published in two preprint papers, show that two doses of the Pfizer vaccine offered levels of protection against covid-19 that were similar to levels from previous SARS-CoV-2 infection.
Read the full article at: BMJ
