London - A jab against coronavirus should last for several years at least, said the British scientist whose own vaccine project is the global front-runner.
Professor Sarah Gilbert told British MPs she was optimistic that a vaccine would provide "a good duration of immunity".
She is the world-renowned expert leading an Oxford University team devising a vaccine, so her claim could help to dispel the fears over how long protection against Covid-19 might last.
Concerns had been raised after those with other types of coronavirus – which are less dangerous and cause the common cold – were able, in tests, to be reinfected within a year.
But Professor Gilbert told the Commons science and technology committee there may be a better result from a vaccine than the natural immunity acquired when individuals simply recover from a virus.
She said: "Vaccines have a different way of engaging with the immune system, and we follow people in our studies using the same type of technology to make the vaccines for several years, and we still see strong immune responses.
"It’s something we have to test and follow over time – we can’t know until we actually have the data – but we’re optimistic based on earlier studies that we will see a good duration of immunity, for several years at least, and probably better than naturally-acquired immunity."
Asked for a timeline on the vaccine, after the prospect was raised of facing the winter without one, Professor Gilbert told the committee: ‘I hope we can improve on those timelines and come to your rescue.’
About 8 000 Britons are taking part in a major trial of the Oxford vaccine, which is being manufactured by pharmaceutical firm AstraZeneca. But, as rates of coronavirus have fallen in the country, researchers are also aiming to vaccinate 4 000 individuals in Brazil and 2 000 in South Africa.
The key question is whether the vaccine will protect them from becoming infected, or simply make them less ill. It may also work less well in older people because their immune systems are weaker.