“The other potential is that you boost your antibody levels so high from whatever vaccine you have that there’s enough to go around and you cope with the variant.
“We’ve certainly seen in this paper that the antibody levels are so good, really after the first two weeks, that we are pretty confident that this should be very helpful against the Brazilian variant.”
Asked if he is surprised how well the vaccines have worked in older people, he said: “We were. When we sent these samples to Porton Down they said ‘we can’t give you results right now because we’ve got to dilute them because they’re so high, they’re off the scale’.
“The antibody levels were so high that they’d gone above the thresholds so they had to dilute them.”
But he added it will be crucial to see how long antibody levels are maintained after people have had a Covid-19 vaccine.
“It will be important to assess that and whether they wane at different rates in people of different ages,” he said.
“I think that’s something that we have to watch out for.”
Although the new study did not look at the Oxford University/AstraZeneca vaccine, Prof Moss said the evidence for the jab is that “it’s very, very effective”.
He added: “The UK has a strong portfolio of vaccines – Pfizer, AstraZeneca, we’ve got Moderna coming very soon, and Novavax as well.
“So yes, I think it’s possible that we can have very broad vaccine coverage across the UK very quickly.”
On T cell responses, Prof Moss said they are “better against variants overall” than antibodies, but he added the role of T cells in fighting coronavirus is still uncertain.
“I do think cellular immunity is very important,” he said, adding that a third of people in the study had no cellular responses detected.
“We know that, as people age, their cellular and immune responses are more difficult to elicit.
“Even influenza vaccines are much less effective in older people so that’s something that we will keep an eye on very closely.”
Prof Moss also said the UK’s plan to exit lockdown appears to be “on track”, with policies to control variants, the development of new vaccines and a strong immunisation programme.
“I think we can be confident about gaining control of variants with the current plans, and also leaving lockdown,” he said.
First author on the paper, Dr Helen Parry, a National Institute for Health Research academic clinical lecturer at the University of Birmingham, said: “Our research provides further evidence that the mRNA vaccine platform delivers a strong immune antibody response in people up to 96 years of age and retains broad efficacy against the P.1 (Brazilian) variant, which is a variant of concern.”
