It is the sixth time the Holborn and St Pancras MP has been forced into isolation since taking the top job after being a close contact with a Covid case or catching the virus himself. His most recent quarantine is the second time he has caught the virus after last being infected with Covid in October 2021.
On that occasion he returned a positive test on the day of the Budget, meaning he was unable to deliver Labour’s response to Rishi Sunak’s plans for the economy.
When he is freed next week the Labour leader will have spent 57 days in quarantine since the start of the pandemic.
Sir Keir is not thought to have any Covid symptoms but the infection was picked up as part of his regular testing routine.
