The capital’s public health chief Professor Kevin Fenton issued the plea as more testing sites were being opened in south London.
More than half a million adults have been offered tests, including 264,000 in Lambeth, 265,000 in Wandsworth, and 14,800 in SE16 areas of Southwark.
Some 44 confirmed cases of the variant have been found in Lambeth and Wandsworth, with a further 30 probable cases, as well as one case in the Rotherhithe ward of Southwark, say health chiefs.
Professor Fenton, London director for Public Health England, said: “We have had an immense response so far in Lambeth, Wandsworth and Southwark, with thousands of people coming forward to get their PCR tests.
“This effort makes a real difference by enabling us to quickly identify any new cases of the variant and help prevent further transmission, so it remains vital that anyone who has not yet been tested comes forward as soon as possible.”
Some Londoners have had to wait up to two hours for tests and the number of major testing sites in Wandsworth was being doubled today.
However, one of the borough’s MPs, Labour health spokeswoman Dr Rosena Allin-Khan, raised concerns about the “appalling” surge-testing system, which is being run by test and trace.
She said that the only site in her Tooting constituency was testing fewer than 700 people a day — despite the area having about 105,000 residents.
She said people queuing for a test were being handed kits and asked to swab themselves while waiting in line. Dr Allin-Khan said this was “shocking” and would result in many invalid tests.
She tweeted: “I was alarmed to hear that the system for logging who takes each test is not working, so there is no way of tracing people automatically. Instead, people are given a barcode and told to call 119 to register the test themselves. The automated system needs to be set up. Urgently.”
Wandsworth council said it was “grateful” to the thousands of residents who had come forward to get tested. It admitted the scale of the response had resulted in “frustrating” waits for many people. As a result, three more testing sites are opening today and 23 pharmacies are taking bookings for PCR tests.
The new testing sites are at Putney Leisure Centre and car parks in Fernlea Road and Patmore Street. There are already sites at Minstead Gardens, Roehampton, Tooting Leisure Centre and Wandsworth Town Hall car park. There are also 10 testing sites in Lambeth, including at the town hall in Brixton, Brockwell Park and Clapham Common.
People aged 11 and over who live, work or travel through those areas are being urged to take a PCR test, on top of twice-weekly rapid testing. Local restrictions may have to be imposed in London if surge testing fails to stop the spread of the Covid-19 South African variant, a leading disease expert suggested. Professor John Edmunds, epidemiologist at the London School of Hygiene and Tropical Medicine, told ITV’s Peston show: “If these mass testing events don’t work that well ... then it’s possible that we’ll have to impose some sort of local restrictions back in place and nobody wants to do it.”
However, public health chiefs do not expect any restrictions to be imposed in the near future. Asked why people were not being told to stay at home, Professor Fenton told Radio 4’s Today: “The level of infection we are now having across the city is actually quite low.
“So, the combination of factors, the timing of where we are in the phase of the pandemic, and the level of infections that we have, really means that we can allow people to continue to move about.”
A senior government source expressed confidence that the London outbreak of the South Africa variant was under control, adding: “There is no exponential growth in the new variant at present.”
Last night surge testing was expanded to more than 120 streets in the N3 postcode area in Finchley after another case of the South African variant was found. Genomic sequencing results indicate that this case is not linked to the cluster in south London, say Barnet council.