LONDON, UK – The Delta coronavirus variant, first identified in India, is thought to be 60 percent more transmissible than the Alpha variant that previously dominated Britain, a prominent British epidemiologist said on Wednesday.
British Prime Minister Boris Johnson has said that England’s full reopening of the COVID-19 lockout, set for June 21, could be pushed back due to the rapid spread of the Delta variant.
Neil Ferguson of Imperial College London told reporters that estimates of Delta’s distribution advantage over Alpha had diminished, and “we think 60 percent is probably the best estimate.”
Ferguson said modeling suggests that any third wave of infections could compete with Britain’s second wave of winter – fueled by the Alpha variant first identified in Kent, south-east England.
But it was unclear how any increase in hospitalizations would lead to an increase in deaths, as more details were needed on how well the Delta vaccine is well protected against serious diseases.
“It is quite possible that we may see another third wave that is at least comparable in terms of hospitalizations,” he said.
‘I think the deaths are likely to be lower, and the vaccines have a very protective effect … it can be quite worrying. But there is a lot of uncertainty. ”
Britain saw more than 127,000 deaths within 28 days of a positive COVID-19 test, but gave more than three-quarters of adults a first dose of COVID-19 vaccine.
Public Health England has shown that the Delta variant reduces the effectiveness of Pfizer and AstraZeneca shots among those who received only one shot, although the protection is higher for those who received both doses.
Ferguson said up to a quarter of the Delta variant’s transferability advantage over Alpha could possibly be the immune flight of vaccines, saying it was a contribution, but not an “overwhelming contribution” to its advantage.