The government has come under pressure from experts to launch a COVID B plan, which would see some rules reintroduced, such as face masks and working from home, to help protect the NHS.
However, the government has insisted that the current high cases are not yet putting overwhelming pressure on health services.
Speaking to BBC Breakfast, Sir Patrick Vallance said: “No one really knows which direction this is going, but they are clear on the two big variables that could change that.
“One is the decrease in immunity, so if the immunity wanes faster than you expect, you will see a bigger increase, and that’s why it’s so important to do booster shots in vulnerable people and the elderly in particular.
“The second is behavior change, how quickly we go back to pre-pandemic behaviors… if you aggregate the models, most say,” Actually, that sounds pretty flat, don’t expect the really big spikes we have. had in the past, it looks pretty flat, but at a very high level at the moment. ‘
“So the high level is still a concern and from a high level you can go up pretty quickly. “