UK and South African SARS-CoV-2 variants show higher binding affinity to host cell receptor Public health officials are concerned over new severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants emerging in various parts of the world. The B.1.1.7 variant was first found in the United Kingdom and found to have the N501Y mutation that allows it to have a faster transmission rate than previous strains. The B.1.351 variant was detected in South Africa and also has the N501Y genetic mutation observed in B.1.1.7. However, scientists are also concerned over two other genetic mutations — K417N and E484K — that have shown an ability to evade the immune system. Prior evidence has found the B.1.351 variant resistant to neutralizing antibodies produced from either prior infection or vaccination.