Oxford’s 90% vaccine finding was ‘only in younger age groups’

A US official has said the dose of AstraZeneca and Oxford University’s Covid-19 vaccine that was shown to be 90% effective was only tested in people aged 55 and under (John Cairns/University of Oxford/PA)

The dose of AstraZeneca and Oxford University’s Covid-19 vaccine that was shown to be 90% effective was only tested in people aged 55 and under, according to a US official.

Moncef Slaoui, the scientific head of the US’s Operation Warp Speed – the programme to supply America with vaccines – told US reporters that the half-dose regime, which was discovered by accident, was only given to younger age groups.