Boris Johnson's spent a second night in intensive care because of the coronavirus.
Downing Street says the British Prime Minister's in 'good spirits' and doesn't need a ventilator.
Dr Joe Cosgrove is a consultant in intensive care medicine, and explains why a patient would still be there for that length of time.
"The patient hasn't recovered sufficiently to be discharged to a general ward setting where they could continue their rehabilitation.
"That's not to say their condition has deteriorated - it jus means that they're not quite fit enough to be discharged to a ward setting."
