“We haven’t seen many hospitalisations in the UK – a lot of infections for sure – but what matters is are you severely ill or not, are you hospitalised or not?” he said. “And we haven’t seen so many of these hospitalisations in the UK.
“The antibody response is what drives the immediate reaction or defence of the body when you’re attacked by the virus, and the T-cell response takes a little longer to come in, but it’s actually more durable – it lasts longer and the body remembers that longer.”
Although Covid cases in Britain are rising again, with 42,484 recorded on Tuesday, deaths are down 5.5 per cent and hospitalisations by 9.5 per cent since last week.
Ahead of the booster vacciness programme decision, several members of the Oxford/AstraZeneca team, including Prof Dame Sarah Gilbert, said third jabs may be unnecessary because two doses offered such good long-term protection.
Eleanor Riley, professor of immunology and infectious disease at the University of Edinburgh, said a growing number of trials had shown that AstraZeneca initially gives higher levels of T-cells, even if mRNA vaccines like Pfizer are better at producing antibodies.
“Since the AstraZeneca vaccine is slightly better at inducing these T-cells, the implication is that it may provide longer term protection against hospitalisation and death,” she added.
Earlier this month, a team of researchers from University College London published data showing that some people already have T-cell protection against Covid as a result of previous infection with a different coronavirus such as a common cold.
Experts also said high levels of infections in the summer and early autumn meant many people in Britain had gained natural immunity to the virus.
New estimates from the Office for National Statistics and the Covid Infection Survey show that over nine in 10 adults across the UK have antibodies to Covid.