Surge testing is to be carried out in two more areas of London after cases of the South Africa COVID variant were discovered.
The Department of Health and Social Care (DHSC) said additional testing and genomic sequencing was being used in the Camberwell area of south London – in the SE5 postcode – and in parts of Harrow, in the HA2 and HA3 postcodes.
Enhanced contact tracing will be used for people who test positive for the variant, which spreads easier and is associated with reduced immunity.
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People living in the targeted areas are being strongly encouraged to take a COVID-19 test when offered, whether they are showing symptoms or not.
The London Borough of Southwark, which administers the SE5 postcode area, said a case of the South African variant had been found in the Faraday ward area.
The council is delivering tests to properties in the immediate area.
It has also sent letters to about 2,000 properties in a wider area, asking people to take a test if they either have symptoms, or have no symptoms but regularly go out.
They asked residents with further concerns to get in touch at firstname.lastname@example.org or on 020 7525 5000.
Cllr Evelyn Akoto, cabinet member for community safety and public health in Southwark, said: “It is important that we identify how far, if at all, the variant has spread.
“If you’re contacted by the council by letter, please take a test if we ask you to. You can also contact us if you have any questions or concerns.”
Harrow Council said the surge testing had been deployed as a result of “unrelated cases” being detected in Headstone North and Wealdstone.
A statement said: “The council will shortly offer tests to anyone over the age of 16 living or working in a small number of selected streets.
“They will be asked either to complete a home test or book a test at Harrow Arts Centre. The council will also be approaching nearby businesses.
“These streets are in Belmont, Harrow Weald, Hatch End, Headstone North, Marlborough and Wealdstone wards.”
Earlier this month, surge testing was deployed in North Wembley, not far from the affected parts of Harrow, after the South African variant was traced in the area.
In south London, people living in Battersea, Roehampton and Putney Heath were asked five days ago to take a test, even if they were not showing symptoms. That was also due to the South African variant.
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The head of the UK effort to find new variants, Professor Sharon Peacock, said she is most worried about the one from South Africa.
She said that B.1.351 – as it is also known – “is more transmissible but it also has a change in a gene mutation, which we refer to as E484K, which is associated with reduced immunity – so our immunity is reduced against that virus”.
Surge testing has been carried out in a number of places across the UK whenever cases of the South African, Brazilian (P1) and other variants of concern have been found.
As of 10 March, the government said it had identified 234 cases of the South Africa variant and seven cases of the Brazilian variant.