Additional testing is to be rolled out across parts of east and west London to suppress the spread of the South African coronavirus variant.

The Department of Health and Social Care (DHSC) on Thursday said additional testing and genomic sequencing is being deployed in Ealing after a “small number” of new cases of the variant were found.

Further surge testing is also to be carried out in a “targeted area” of the IG1 postcode area of Redbridge, east London, where the variant has also been found, it added.

The department said: “Working in partnership with the London Borough of Ealing, additional testing and genomic sequencing is being deployed within the borough, where a small number of additional cases of the Covid-19 variant first identified in South Africa have been found.”

In a further statement, it added: “Additional testing and genomic sequencing is being deployed to a targeted area within the IG1 postcode in Redbridge, where the Covid-19 variant first identified in South Africa has been found.”

People living in both areas are “strongly encouraged” to take a Covid-19 test when offered, whether they are showing symptoms or not.

It is the latest deployment of surge testing in England in a bid to control and suppress the potential spread of variants.

It comes as new Test and Trace figures showed 84,310 people tested positive for Covid-19 in England at least once in the week to February 17 – down 21% on the previous week and the lowest number since the week to September 30.

Some 86.8% of people who were tested for Covid-19 in England in the week ending February 17 at a regional site, local site or mobile testing unit – a so-called “in-person” test – received their result within 24 hours.

This is up slightly from 85.4% the previous week, and is the highest figure since the week to July 8.

Prime Minister Boris Johnson had pledged that by the end of June 2020, the results of all in-person tests would be back within 24 hours.

Of the 83,000 people transferred to the Test and Trace system that week, 87.9% were reached and asked to provide details of recent close contacts.

The new figures also show that 1,756,402 lateral flow device (LFD) tests for Covid-19, or rapid tests, were conducted in England in the week to February 17, down from a record 2,401,651 the previous week.

The DHSC said the drop coincided with school half-term holidays.

LFD tests are swabs that give results in 30 minutes or less, without the need for processing in a laboratory.

There were 1,116,433 polymerase chain reaction (PCR) tests conducted in the week to February 17. PCR tests are swabs processed in a laboratory.

This is the fourth successive week in which more LFD tests were conducted than PCRs.

NHS Providers chief executive Chris Hopson said: “It is good that the number of positive Covid-19 cases continues to fall, this week 21% fewer than the previous week.

“We are consistently seeing a very high proportion of positive cases being transferred into the Test and Trace system each week. But one in eight of these are still not being reached and asked to provide details of their contacts. More needs to be done to ensure there are no gaps.

“Compared to the start of the year, test turnaround times have improved significantly, but it is vital that we see further progress ahead of restrictions being eased.

“Following the Government’s lockdown road map, Test and Trace must build upon the advances it has made to enable the country to exit lockdown in the safest way possible.

“In particular, it would now be helpful if Test and Trace could report regularly on its own assessment of how ready and able it is to combat any new variant Covid-19 strains that, in future, provide the greatest threat.”