Brits may be forced to follow social distancing rules all year unless a vaccine is 85 per cent effective at stopping infections, ministers have been told.
Modellers have reportedly predicted another huge spike in coronavirus deaths if jabs fail to significantly cut infection rates.
Most experts believe vaccines will reduce transmissions by around 60 per cent under the best case scenario, the Sunday Telegraph reports.
Even if vaccines stopped 85 per cent of transmissions, the current lockdown would still have to remain in place until the end of May to prevent another surge in deaths, according to a University of Warwick paper.