Coronavirus surge testing is spreading across an expanding area of London as more cases of the highly-contagious South Africa variant are found.<br/> Four London <a href="https://www.thenationalnews.com/world/europe/increase-in-surge-testing-in-london-to-contain-south-african-coronavirus-variant-1.1202697">boroughs are now offering surge testing</a> as a response to finding cases of South African mutation, and for the first time the mutation has skipped further afield than the next borough.<br/> The South Africa variant is feared because it is highly contagious and appears to be successful, to some extent, in beating vaccine <a href="https://www.thenationalnews.com/mena/study-finds-south-african-variant-can-break-through-pfizer-biontech-vaccine-1.1200920">protections notably the Pfizer-BioNTech vaccine</a>.<br/> More than half a million people have been offered tests in the four boroughs – Wandsworth, Lambeth, Southwark and Barnet - where the total population is 1.37 million. The first cases were found in Wandsworth and Lambeth, both neighbouring boroughs in south London, then Southwark, the next borough eastwards on the south bank of the River Thames, and finally Barnet in north London. In Barnet, a PCR testing facility has been set up at Finchley Central station while officials go door-to-door offering home tests, after one confirmed case of the South African mutation.<br/> "We will start testing people for this variant in specific postcode areas affected in N3 or those who shop on the local high street," a statement from Barnet council said.<br/> It added that the case cannot be traced back to international travel. People who have been in contact with the patient have been traced have all been asked to self-isolated.<br/> Wandsworth, Lambeth and Southwark are all neighbouring boroughs and on the south bank of the River Thames. Only Barnet is further afield. On Wednesday, London mayor Sadiq Khan, said: "Additional testing will be taking place in a targeted areas... This testing is essential to help monitor and suppress the spread of the virus.<br/> As London battled the variant, Sir John Bell, regius professor of medicine at the University of Oxford, who also had a role in developing the AstraZeneca virus said a mix-and-match approach to vaccines could be a way to tackle mutations. “This is a really interesting strategy, probably more interesting in terms of dealing with variants,” he said. “We believe if you mix the vaccines you will get a different type and a wider and stronger immune response. “That would mean we are better able to deal with the South African variant and dozens of others popping up all over the world. "As you start to mix and match, you will start to get an enhanced and more durable response."<br/> He added more science must be completed before adopting mix-and-match vaccinations.