"It's of concern to scientists that we are running this hot this early in the autumn season," he added.
While he acknowledged that hospital admissions have levelled off in the last four days, he said he was worried deaths were rising and there were signs infections were starting to "penetrate" older age groups.
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Asked about Sir Jeremy Farrar's resignation from the Scientific Advisory Group for Emergencies (SAGE), he said: "I think it's very clear he felt that a lot of the information that the government need to have from scientists has now been given, and he recognised the need that he had to really re-focus on his work at the Wellcome Trust."
On the subject of masks, Prof Van-Tam said they are beneficial "but they are probably most useful when used in combination with other things".
He said he did not think people should wear face coverings while seated in indoor settings that involve food or drink, but recommended them for entering, leaving and moving around venues.
He said in cinemas and theatres "you're not interacting with anyone in there other than the audience or the actors on the screen, you're not interacting with the audience, you are seated quite close together, and for most people there should be relatively little personal expense involved in wearing a face covering in those kinds of settings."
He said it would be "very socially inhibiting" to wear masks in clubs, adding: "I think if the epidemiology gets worse in the UK that on its own would not be enough in those kinds of venues."