The NHS could be at risk of being overwhelmed if the Indian variant is more than 30 per cent more transmissible than the Kent strain, according to government modelling.
Research for the government’s Sage advisory group by the University of Warwick has suggested that unless the Indian strain is less than 20 per cent more transmissible than the Kent variant there will be significant risk to the NHS.
Boris Johnson said yesterday the government was “anxious” about the variant and hinted at local lockdowns as concern grew about the spread of the B.1.617.2 strain.
Four hundred suspected cases of the variant of concern have now been detected in London, official figures have revealed.
Ministers are poised to order further action to tackle the spread of the variant of concern as new research shows cases have more than doubled in a week.
Scientific advisers believe that local lockdowns could curb transmission until the vaccination programme is complete.
They noted that “tier 3” measures last year, which included banning indoor gatherings and closing hospitality businesses, appeared to work. However, it is not clear what restrictions would be needed to contain a more transmissible variant.
Delaying the final step of the road map out of lockdown until all adults have been invited to have their vaccination is another option, advisers believe.
Yet ministers have received no formal recommendations given the huge uncertainties about the spread of the variant.
Professor Neil Ferguson, from Imperial College London, is part of the “variant technical group” that is assessing the threat.
“At the moment we have a concerning signal, but we can’t be completely sure it’s indicative of this virus being dramatically more transmissible,” he told The Times.
According to Prof Ferguson, disentangling sociological and virological factors was challenging, particularly after a swathe of imported cases found in coronavirus hotspot areas.
If all restrictions are lifted as planned next month, a variant that is 40 per cent more transmissible could create a peak of 6,000 hospitalisations per day in August, far exceeding the January peak, of 3,768.
It is possible that the daily rate could reach 15,000, modelling shows.
Instead, if ministers call off the end to restrictions, they could limit this summer peak to 3,000 hospital admissions per day, about the same as last April, but that number could also reach 8,000 per day.
Even if the vaccines work just as well against the new strain, a strain that is 50 per cent more transmissible would lead to 10,000 admissions per day, and possibly up to 20,000.
If the variant is 50 per cent more transmissible, hospitalisations in England are likely to reach 5,000 per day even if the lifting of restrictions is delayed, and could reach 14,000.
There is huge uncertainty about the estimates, and far lower peaks are also considered possible.
Meanwhile the vast majority of younger people, who spread the virus more, have not been inoculated.
Although vaccines cut the risk of hospitalisation they do not eliminate it, and some vulnerable people have yet to receive the jab.
This means that although it takes high infection rates to put a strain on the NHS, a big surge is still dangerous.
Separate modelling for the London School of Hygiene and Tropical Medicine suggested that there will be 1,000 deaths per day in August if the variant is 50 per cent more transmissible.