Avaccine considered a frontrunner in the race to protect the global population from Covid-19 has produced a robust immune response in elderly people, the group at highest risk from the disease, according to two people familiar with the finding. The discovery that the vaccine being developed by the University of Oxford, in collaboration with AstraZeneca, triggers protective antibodies and T-cells in older age groups has encouraged researchers as they seek evidence that it will spare those in later life from serious illness or death from the virus.
Age has emerged as the principal risk factor for a severe bout of Covid-19. However, the immune system weakens with age, raising concerns that the very group that most needs the protection of a vaccine may generate the least effective response to one.