Covid-19: Single vaccine dose is 33% effective against variant from India, data show | The BMJ

The UK government has been urged to speed up giving two doses of the covid-19 vaccine after data showed a single dose was only 33% effective against the B.1.617.2 variant first detected in India, which continues to see a rapid growth in cases in the UK.

A preprint paper released by Public Health England on 22 May showed that between 5 April and 16 May the Pfizer vaccine was 88% effective, two weeks after the second dose, against the B.1.617.2 variant and 93% against B.1.1.7, known as the UK or Kent variant.1 The AstraZeneca vaccine was 60% effective against B.1.617.2 at two weeks after the second dose and 66% against the Kent variant.

But both vaccines were only 33% effective against symptomatic disease from B.1.617.2 three weeks after the first dose, whereas they were 50% effective against B.1.1.7.

Christina Pagel, director of the Clinical Operational Research Unit at University College London and a member of the Independent Scientific Advisory Group for Emergencies, said that, given these data, the government should not proceed to the next stage of its roadmap to ending lockdown before more people were fully vaccinated with two doses, given that cases of the B.1.617.2 variant rose sharply in the week to 19 May.23 

Source: Covid-19: Single vaccine dose is 33% effective against variant from India, data show | The BMJ