Omicron may be significantly better at evading vaccine-induced immunity, but less likely to cause severe disease

The Omicron variant of SARS-CoV-2 may be significantly better than previous variants at evading vaccine-induced antibodies, according to new research from Cambridge – but preliminary evidence suggests it is less likely to cause severe COVID-19 illness in the lungs. As the SARS-CoV-2 virus replicates and spreads, errors in its genetic code can lead to changes in the virus. On 26 November 2021, the World Health Organization designated the variant B.1.1.529, first identified in South Africa, a variant of concern, named Omicron. The variant carries a large number of mutations, leading to concern that it will leave vaccines less effective at protecting against infection and illness. Working in secure conditions, a team led by Professor Ravi Gupta at the Cambridge Institute of Therapeutic Immunology and Infectious Disease, University of Cambridge, created synthetic viruses – known as ‘pseudoviruses’ – that carried key mutations found in the Delta and Omicron strains. They used these to...