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Covid-19 Primary Care Resources


Covid variants and vaccine effectiveness


vaccines destroyed


An update on Variants of Concern and UK vaccine effectiveness data

This information is sourced from The PHE Greenbook, a Gov UK press release, a medRxiv preprint study, The Guardian the WHO and Nature:

Variants of Concern

The WHO have introduced a naming scheme for Variants of Concern which aims to avoid confusion and stigmatisation:

WHO labelPango lineageEarliest documented samples
AlphaB.1.1.7UK, Sept 2020
BetaB.1.351South Africa, May 2020
GammaP.1Brazil, Nov 2020
DeltaB.1.617.2India, Oct 2020

UK Vaccine effectiveness

Up to three-quarters of new UK Covid cases are now thought to be caused by the variant first detected in India (Delta)

Updates on the real world effectiveness of Covid vaccines are now published by PHE on a weekly basis

In those who had had 2 doses of a vaccine

  • The Pfizer vaccine is 88% effective against symptomatic disease from the Delta variant 2 weeks after the second dose, compared to 93% effectiveness against the Alpha variant
  • 2 doses of the AstraZeneca vaccine is 60% effective against symptomatic disease from the Delta variant compared to 66% effectiveness against the Alpha variant

In those who had had 1 dose of a vaccine

  • Both vaccines are 33% effective against symptomatic disease from Delta , 3 weeks after the first dose compared to around 50% effectiveness against the Alpha variant

Protection against hospitalisation

  • Two doses of Covid vaccine provide over 90% protection against hospitalisation with severe Covid. This level of protection been maintained since the delta variant was introduced to the UK

Written by Dr Poppy Freeman

Sources

CDC: When You’ve Been Fully Vaccinated, How to Protect Yourself and Others

Published: 16/07/2019

HE: COVID-19 Greenbook chapter 14a

Published: 01/07/2021

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Nature News Coronavirus variants get Greek names — but will scientists use them?

Published: 01/06/2021

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WHO Tracking SARS-CoV-2 variants

Published 31/05/2021

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The Guardian Three-quarters of new UK Covid cases could be India variant, says Hancock

Published 27/05/2021

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GOV UK Press release: Vaccines highly effective against B.1.617.2 variant after 2 doses

Published: 22/05/2021

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medRxiv: Effectiveness of COVID-19 vaccines against the B.1.617.2 variant

Published: 24/05/2021