There is to be a large expansion of the number of people being asked to shield in England.
An extra 1.7 million people are expected to be added to the 2.3 million already on the list. Half of the group have not yet been vaccinated so will now be prioritised urgently by their local GPs.
It comes after a new model was developed that takes into account extra factors rather than just health.
This calculation includes things such as ethnicity, deprivation (by postcode) and weight to work out a person's risk of becoming seriously ill if they were to catch Covid. It also looks at age, underlying health issues and prescribed medications.
Prof Andrew Hayward, a member of the New and Emerging Respiratory Virus Threats Advisory Group (Nervtag), which has been involved in the modelling, said it considered a "combination of factors" such as age, ethnicity and chronic illness and put them together to reach a score.
He told BBC Radio 4's PM programme that this score could "more or less order people in the population according to their level of risk" and "identify those at the top of that range to say, 'you should be prioritised for vaccine and you have a level of risk that is similar to those on the shielding list'".
Source: BBC News, 16 February 2021