The government changed the official advice to those who are most vulnerable during the pandemic.
In an address to the nation on Saturday, Boris Johnson confirmed England would go through a second ban.
He also said that people over 60 and those who are clinically at risk should take special care to follow the rules and minimize their risk of infection.
In addition, people in this category should minimize contact with other people during the second ban.
People who have been sent a letter saying to shield for the first time are advised not to go to work. the Liverpool Echo reports.
This is the same advice the government issued in March prior to the initial lockdown.
However, formal shielding – where people are told not to leave their homes for any reason – is not being introduced.
Professor Whitty said it was right that vulnerable people who had screened during the previous lockdown continued to take extra precautions this time, adding, “We learned a lot with the screening program last time – some of the things worked, but some of things not.
“There have been some practical problems as well as the problem of people having significant problems with loneliness and feeling completely cut off from society.
“We are trying to avoid these drawbacks of shielding while reaffirming the message that people who are particularly at risk must take even greater precautions than the general public.”
Mr Johnson added, “I know how tough the shield was and we are not going to ask people to shield again the same way.
“But we ask those at high clinical risk to minimize contact with others and not go to work when they can work from home.”