Brits have "relaxed too much" about the dangers of coronavirus over summer, the deputy chief medical officer for England has warned.
Professor Jonathan Van-Tam has cautioned that the steep rise in coronavirus cases over the past few days is cause for "great concern", and indicates that the country could have a "bumpy ride" ahead.
2,948 positive tests were confirmed in the UK on Monday September 7 after 2,988 were reported the previous day - representing the highest daily figure since May.
While hospitalisations and deaths remain relatively low, there is concern that cases - currently dominated by younger people - will seep through into older populations and result in a spike in hospitalisations and deaths.
Prof Van-Tam said the 17-21 age group have been most heavily impacted.
Prof Van-Tam also said: "This is a big change. It’s now consistent over two days and it’s of great concern at this point.
"We’ve been able to relax a bit over the summer, the disease levels have been really quite low in the UK through the summer but these latest figures really show us that as much as people might like to say “oh well it’s gone away” – this hasn’t gone away.
"And if we’re not careful, if we don’t take this incredibly seriously from this point in we’re going to have a bumpy ride over the next few months."
A number of areas have experienced a spike in coronavirus cases, including Birmingham, Gateshead and Leeds. Caerphilly in Wales is the latest area that looks to be heading for a local lockdown.
The seven-day coronavirus rate for the whole of the UK currently stands at 21.3 per 100,000 - higher than the 20 per 100,000 threshold that the Government uses to levy quarantine restrictions on other countries.
The government is now said to be considering imposing new national restrictions on gatherings.
Currently, it is against the law to gather in groups of over 30 - but the government is considering dramatically reducing this number.