Schools and other essential services such as fire and rescue could struggle to function if Covid-19 cases are allowed to continue to rise, a government adviser has warned.

Calum Semple, professor of outbreak medicine at the University of Liverpool and a member of the Scientific Advisory Group for Emergencies (Sage), said essential services could be affected in areas with the highest infection rates unless measures are taken to bring the epidemic under control.

“When you start to get levels of infection like this in the community, it starts to affect other services such that so many teachers will be off sick with Covid that the schools will have difficulty delivering education,” he said.

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Prof Semple told BBC Breakfast that the health system in Liverpool is currently “highly, highly stressed” by having so many Covid-19 cases.

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“There’s also a high level of [NHS] staff absence because of, essentially, burnout but also sickness - and that, within our infrastructure within Liverpool, is cause for concern,” he said.

“And these cases are from infections that occurred 10 days ago.

“The current infections… are baked into the system, so we’re predicting quite a dire situation within a week or so, and that’s why we’ve been making these very public announcements.”

Prof Semple said that unless something happens to stem the spread of the coronavirus, “the numbers will keep rising, there’ll be further hospital admissions and further deaths”.

He added: “But it’s not just the Covid disease in the hospital we have to think of.

“This isn’t just now about protecting the NHS, this is actually now about protecting other aspects of how we run our communities in Liverpool.”

Prof Semple said that, in his opinion, Manchester needs to move into Tier 3 measures, as do other regions.

He added: “There is always going to be some friction between the focus on the numbers of cases and the need to keep the economy going, but from a purely academic point of view, where I’m coming from, if you allow the numbers to rise it inevitably has an impact on the economy because you start to lose the capacity to deliver these other essential services.”