Britain is increasingly confident that vaccines work against the coronavirus variant first identified in India, Prime Minister Boris Johnson said on Wednesday.
And a leading epidemiologist said it might be spreading less quickly than feared.
Mr Johnson had said the emergence of the B1617.2 variant might derail his plans to lift England’s lockdown fully on June 21, but on Wednesday he said the latest data was encouraging.
“We have increasing confidence vaccines are effective against all variants, including the Indian variant,” he told Parliament.
Mr Johnson said last week that the extent to which the variant could disrupt the end of lockdown would depend on how much more transmissible it was.
Health Minister Matt Hancock said that 2,967 cases of the variant had been found, and a decision on easing social restrictions would not be made until June 14.
England’s deputy chief medical officer, Prof Jonathan Van-Tam, said that the Indian variant was somewhere between a few per cent and 50 per cent more transmissible than the Kent variant.
Prof Van-Tam said data should provide a clearer picture next week.
“I think most people feel it is going to be somewhere in the middle rather than at the extremes of that band,” he said.
Neil Ferguson, an epidemiologist at Imperial College London, said there was a “glimmer of hope” from the latest data that the transmissibility of the variant might be lower than first feared.
“The magnitude of that advantage seems to have dropped a little bit with the most recent data,” Dr Ferguson told BBC radio.
He said that while it was likely vaccines would continue to protect against severe disease, their efficacy against infection and transmission might be reduced.
Dr Ferguson said the initial rapid growth of B1617.2 was among people who had travelled, who were in multigenerational households or in deprived areas.
He said the ease of transmission might not be replicated in other settings.
Graham Medley, professor of infections disease modelling at the London School of Hygiene and Tropical Medicine, said while the variant was growing quickly in some spots, “we haven’t yet seen it take off and grow rapidly everywhere else”.
“One of the key things we’ll be looking for in the coming weeks will be: how far does it spread outside of those areas,” Prof Medley, also a member of the government’s Scientific Advisory Group for Emergencies, told Reuters.
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