A coronavirus vaccine professor at Oxford University says there is now ‘little chance’ of proving if it works due to low transmission rates in the UK.
Professor Sarah Gilbert, leading the University of Oxford vaccine trial, said that when Covid-19 transmission was high, lockdown was imposed to bring the rate down.
But since then rates have dropped, and the trial relies on a sufficient number of volunteers to have been exposed to the virus to see whether a vaccine protects them or not.
https://www.mirror.co.uk/news/uk-news/vaccine-professor-oxford-university-says-22241101