Dozens of further confirmed cases of the Delta variant of coronavirus have been recorded in Watford, new figures reveal.

Health Secretary Matt Hancock said the Covid-19 mutation that originated in India now makes up 91 per cent of new cases in the UK, with evidence suggesting it may be more dangerous than the Alpha – formerly known as the Kent – variation.

Public Health England figures show 132 cases of the Delta variant had been recorded in Watford by June 9.

That was 76 more than the 56 cases recorded the week before.

Those identified in the latest week were among at least 2,500 cases of the VOC-21APR-02 mutation recorded across the East of England – the sixth-worst affected of England's nine regions.

The North West – where variant hotspots Bolton and Blackburn are located – continued to have the highest numbers identified – 16,825 Delta variant cases have been recorded there.

Public Health England said on Friday (June 11) that 42,323 cases of the Delta variant have been confirmed in the UK, up from 29,892 a week ago.

The increase in confirmed cases has been driven partly by a reduction in test turnaround times and a faster process for identifying cases of the variant, PHE said.

Growth rates for Delta cases are high across all parts of the country, it added, with cases doubling every 4.5 days in certain areas.

Liberal Democrat MP Layla Moran, chairwoman of the All-Party Parliamentary Group on Coronavirus, said: “These figures should set alarm bells ringing in Government as we approach June 21.

“The Government must immediately explain to the public whether this exponential growth suggests the country is in line for a severe third wave, and if so what it is doing to prevent this.

“As well as hospitalisations and deaths, ministers need to consider the debilitating impact of long Covid which is already affecting an estimated one million people.

“Simply letting this highly contagious strain of the virus rip through unvaccinated younger people risks leaving more with long Covid and creating a ticking time bomb for our NHS.”

Different PHE figures show that 42 people across England had died with the Delta variant as of June 7.

Of them, 23 were unvaccinated, seven had received their first dose more than 21 days prior and 12 died more than two weeks after receiving their second jab.

The figures also show that two thirds of the 1,234 people who attended A&E in England between February 1 and June 7 and who were confirmed as having the Delta variant of coronavirus were unvaccinated.

Dr Jenny Harries, chief executive of the UK Health Security Agency, said: “With numbers of Delta variant cases on the rise across the country, vaccination is our best defence.

“If you are eligible, we urge you to come forward and be vaccinated.

“Remember that two doses provide significantly more protection than a single dose.

“However, while vaccination reduces the risk of severe disease, it does not eliminate it.

“With data showing that Delta is significantly more transmissible than Alpha, it is just as important as ever to follow public health advice, which has not changed.

“Get vaccinated, work from home where you can and remember ‘hands, face, space, fresh air’ at all times.

“These measures work, and they save lives.”