coronavirus strains.They would be introduced in a bid to stop the spread of new variants which could potentially be resistant to Covid-19 vaccines.Officials are said to be drawing up plans which would see lockdowns combined with surge testing and detailed tracing to wipe them out.Boris Johnson is due to set out his roadmap for ending the national lockdown on Monday, February 22.The Prime Minister said it would be based on “data, not dates”, with rules being eased in stages.He said the path would be "cautious but irreversible".But the Times quoted sources saying the Government was aware localised restrictions might still be needed.One said there was a big question about “what you do when lockdown does start lifting and we see variants that.