Professor Neil Ferguson said the finding that lockdowns cut the Covid death rate by just 0.2% does not significantly advance understandings of how effective the draconian measure is.
No10 has only 9 days to meet the ambitious target of boosting every eligible Briton by the end of 2021 as the Covid booster programme once again misses its elusive 1million-jabs-a-day target.
Omicron tightened its grip on the nation as the UK recorded 90,418 new infections on Saturday, as SAGE advisers warned cases could hit one million infections each day by December 25.
The festive season is in the balance as SAGE experts raise alarm that the number of infections could reach two million by the end of the month without tougher restrictions.