Dr Jamie Lopez Bernal, a consultant epidemiologist for immunisation at the UK Health Security Agency (UKHSA), said it was “seeing an increase in Covid-19 across all indicators, including hospitalisations”.

Experts fear existing vaccines may not provide the same level of protection against new variants, which are several mutations away from those that initially spread.

The main “Flirt” variants, known as KP.2 and KP.3, accounted for a combined 40 per cent of Covid in April – the last time UKHSA published a breakdown of the variants.

While KP.2 was the more prevalent of the two then, it is believed that KP.3 is the driving force behind a summer wave.

Both are mutations from the previously dominant JN.1 variant, and scientists believe they allow the virus to spread more easily.

Prof Woolhouse added: “The waves continue to be driven by a combination of new variants and a partial waning immunity to infection.”

He said there would be “continuing circulation of the virus and fluctuating levels of disease, hospitalisations and deaths” until there is a shift where most people have been exposed to Covid while they are young.

“It will result in a build-up of immunity that will make them much less vulnerable when they are elderly and frail. Even so, we may continue to offer vaccines to the most vulnerable groups. But to all intents and purposes Covid-19 will become just another common cold.”