Oxford University research suggests herd immunity is 'unachievable' with Delta
Double-jabbed people who catch the Indian variant are just as likely to develop symptoms and spread Covid as the unvaccinated, a major study has found.
The Oxford University research suggests herd immunity is 'unachievable' because vaccines do not significantly reduce transmission of the virus.
This means infected people 'shed' the same amount of virus when they cough or sneeze, regardless of whether or not they have been jabbed.
The Oxford study, based on data from 700,000 Britons, is the largest yet to evaluate vaccine effectiveness against the Delta variant, which has been dominant in the UK since May.