The majority of cases of the so-called Indian variant in the UK have been detected in Bolton, Blackburn and Merseyside.

Data from Public Health England (PHE) shows a rise in cases of the Indian variant of concern from 520 to 1,313 this week in the UK, with the agency saying infections were “rising in the community” and it was assessing the impact and severity.

Although the Indian variant is thought to be highly transmissible, vaccines are expected to be effective against it.

The majority of the 1,313 cases of the B16172 variant, which was first identified in India, are in England, with PHE reporting 35 in Scotland, 11 in Wales and 12 in Northern Ireland.

The Department of Health and Social Care said most cases are in the North West of England, with some in London.

The variant has been detected in Bolton, Blackburn and Sefton in Merseyside, which have all seen rates rise rapidly.

Bolton has the highest rate of any local area in England, with 553 new cases in the seven days to May 9 – the equivalent of 192.3 per 100,000 people.

This is up from 84.9 in the seven days to May 2.

Erewash in Derbyshire has the second highest rate in the country, but this has been driven by an outbreak at Wilsthorpe Academy in the town of Long Eaton, according to Derbyshire County Council’s director for public health, Dean Wallace.

Blackburn with Darwen in Lancashire has the third highest, up from 54.1 to 107.6, with 161 new cases, followed by Bedford where the rate has more than doubled from 39.8 to 86, with 149 new cases.

Blackburn with Darwen Council said on Thursday that it would be offering vaccines to all over-18s from next week following the increase in cases, but later said that, although additional vaccine clinics are being set up, the jab will only be offered to those eligible under current Government guidance.

Greater Manchester mayor Andy Burnham has submitted a request to the Joint Committee on Vaccination and Immunisation for all over-16s in Bolton, along with the rest of the Greater Manchester area, to receive a vaccination “to mitigate the risks of spread in those communities where we are seeing more transmission”.