Map reveals how Delta variant has run rampant in weeks

The Delta variant is now dominant in nearly every local authority across England

Proportion of Delta variant Covid cases across England as of 26 June (Contains Ordnance Survey data © Crown copyright and database right 2019 Contains Public Health England data © Crown copyright and database right 2020 Office for National Statistics licensed under the Open Government Licence v.3.0)

The Delta variant, first identified in India, is currently the dominant strain of the coronavirus in the UK, making up around 95 per cent of new cases.

Data from the Wellcome Sanger Institute show how the mutated strain of the virus – first detected in the UK in April – has been able to spread with impunity across England in a matter of weeks.

A month ago, most areas had five or fewer cases related to the Delta variant, and only 40 of 127 local authorities in England had detected it within their infections. But over the past four weeks, the institute found, it has become the most prominent strain in nearly every area in England.

(Contains Ordnance Survey data © Crown copyright and database right 2019 Contains Public Health England data © Crown copyright and database right 2020 Office for National Statistics licensed under the Open Government Licence v.3.0)

The highest case counts are seen in the north west regions, where the variant was first discovered, with Manchester reporting nearly 500 Delta infections every week up to 26 June.

Other hotspots include Birmingham, Liverpool and Cornwall, which were all experiencing more than 250 cases of infection with the mutant strain each week up to 26 June.

The institute’s genomic surveillance of Covid variants has also shown how the Alpha variant, first discovered in Kent in December, was replaced by the Delta variant as the most frequently occurring strain in Mid-May.

Scientists have said the the Delta variant has a biological advantage over older strains of the virus, saying it is 40 to 60 per cent more transmissible than previous strains of the virus.

The spike in coronavirus cases driven by the spread of the Delta variant led the government to delay the full lifting of lockdown restrictions by a month to 19 July, in order to first vaccinate as much of the population as possible.

Cases continue to rise, however, with more than 30,000 new infections recorded on Wednesday.

Despite the rising case count, earlier this week Boris Johnson announced that he was hopeful that England would be released from all remaining lockdown restrictions – including social distancing and mask-wearing – on 19 July.

The final decision for lifting the lockdown will be made on 12 July.