Boris Johnson refuses to rule out a THIRD national lockdown after Sage model warns Britain needs to increase vaccination rate from 350,000 people a week to TWO MILLION to avoid 45,000 extra deaths from mutated Kent coronavirus The Prime Minister warned people it will 'continue to be difficult' because of the new strain of coronavirus Members of SAGE sub-group SPI-M said the variant will infect a lot more people because it spreads faster The variant is concentrated in London, the East and South East of England but is spreading elsewhere Two cases of a second, potentially even faster spreading variant from South Africa were announced last night