Both of the most-used vaccines in the UK are ‘highly effective’ against the Indian strain of Covid-19, Public Health England has said.
However, both vaccines are less effective against the Indian strain than against the currently dominant strain in the UK, which was first identified in Kent last year (B.1.1.7).
Two doses of the Pfizer vaccine is 88% effective against symptomatic disease from the B.1.617.2 variant, while the AstraZeneca vaccine is 60% effective, the PHE study found. This compares to 93% (Pfizer) and 66% (AZ) effectiveness against the Kent strain.
However, both vaccines were only 33% effective against the Indian variant after one dose, compared to around 50% against the Kent strain.
PHE expects ‘even higher’ protection against hospitalisation and death from both vaccines but said there was not yet sufficient numbers of cases or follow-up time.
The analysis took into account data from all age groups, and several ethnicities, since the Indian variant emerged (5 April), in 1,054 individuals who were confirmed to have caught the virus via genomic sequencing.
Although the AZ vaccine appeared less effective than the Pfizer vaccine, PHE said this ‘may be explained’ by the later rollout of the AZ vaccine. It also pointed to ‘other data’ suggesting the AZ vaccine ‘takes longer to reach maximum effectiveness’ following vaccination.
PHE will continue to evaluate effectiveness ‘over the coming weeks’, it added.
The news comes amid proof of further spread of the Indian variant in England, with Bedford, Burnley, Hounslow, Kirklees, Leicester, and North Tyneside added to areas where additional measures are being deployed.
It follows work already being done to tackle rising rates of the variant of concern in Bolton and Blackburn.
It also comes as the Government announced that 37.9 million people in the UK have now had a first vaccine dose and 22.6 million people have had two doses.
The latest group to be invited to book a vaccination were people aged 32-33.