Booster jabs “massively” strengthen the body’s defences against Covid, according to key results that have raised hopes of strong protection from the Omicron variant.
A third dose not only increased antibody levels thirtyfold, but roughly tripled levels of T-cells, a part of the immune system that experts believe could be the critical weapon against the heavily mutated Omicron strain.
• Germany has imposed a de-facto lockdown on the unvaccinated
• EU health chiefs estimate that Omicron could displace Delta by the spring
• The total number of Omicron case across Britain has risen to 42
• Omicron has become dominant in South Africa as infection rates surge
The long-awaited results of the trial underpin Britain’s decision to press ahead with a mass booster campaign. They found that Pfizer and Moderna performed best as boosters out of six
vaccines that were tested.
Early data from the study was central to the decision by the Joint Committee on Vaccination and Immunisations to offer booster jabs in September and cut the gap between second and third doses to three months. Full results reveal how widely booster jabs can rally the immune system, making scientists cautiously optimistic as the world prepares for a wave of Omicron cases.
“This T-cell response gives us hope,” said Professor Saul Faust, chief investigator of the trial, which is published today in The Lancet. “The T-cell responses to [the original Wuhan variant], Beta and Delta are very similar. And we would hope that we would see something similar for Omicron. Our hope as scientists is that protection against hospitalisation and death will remain intact.”