Guidance: PHE monitoring of the effectiveness of COVID-19 vaccination

Public Health England

February 22
17:09 2021

PHE monitoring of the early impact and effectiveness of COVID-19 vaccination in England

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On 8 December 2020, the UK became the first country to roll out a COVID-19 vaccination programme, initially using the Pfizer/BioNTech vaccine.

Since the beginning of the programme, Public Health England has been monitoring the effectiveness of the vaccines in the real world and has now published its first analysis of the impact of the Pfizer/BioNTech vaccine on:

  • symptomatic disease
  • hospitalisation
  • death
  • infection (symptomatic or asymptomatic)

SIREN study

Early data from PHEs SIREN study shows a promising impact on infection in healthcare workers aged under 65. Healthcare workers in the study are tested for coronavirus (COVID-19) every 2 weeks whether or not they have symptoms.

Data shows 1 dose reduces the risk of catching infection by more than 70%, rising to 85% after the second dose. This suggests the vaccine may also help to interrupt virus transmission, as you cannot spread the virus if you do not have infection.

Published 22 February 2021
Last updated 22 February 2021 +show all updates
  1. Added link to the SIREN study.

  2. First published.

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