A trial volunteer said it was a “great feeling” to be involved in the development process as new data suggested a UK-developed Covid-19 vaccine could be up to 90% effective.

Sarah Hurst, 47, took part in the AstraZeneca and Oxford University research, receiving two jabs of either the experimental vaccine or a placebo.

She said there was a “tiny sense of pride” at her involvement, but paid tribute to the scientists and researchers who developed the vaccine.

Ms Hurst, a journalist from Goring-on-Thames in South Oxfordshire, told the PA news agency: “It’s really the developers and everyone who’s done all the work, all the medical students who are constantly all day meeting the vaccine participants and testing them and being on the front line.

“But it’s good, it’s a great feeling to help to make a vaccine.”

Jack Sommers, another volunteer on the trial, said it was hard to believe how quickly scientists had developed the vaccine.

“I can’t help but take my hat off to the scientists,” Mr Sommers, 35, told PA.

“I remember six months ago sitting in a hospital watching a safety video, with Professor Matthew Snape at Oxford University talking in quite careful, deliberate, cautious terms about how this vaccine might work or it might not work.

“Now it seems amazing that we’re here six months later and that jab is very effective at stopping coronavirus.

“It’s not where I thought we’d be six months ago, it’s not even where I thought we’d be a month ago, but it’s testament to the work of so many people, so many extraordinary people.”

Both Mr Sommers and Ms Hurst received two shots of either the experimental Oxford vaccine or a placebo.

Mr Sommers, a freelance journalist from south-west London, experienced mild side effects – a slightly raised temperature and a pain in his shoulder – while Ms Hurst felt none at all.

Volunteers receive no information about how the trial is going so have been following the progress in the media along with everybody else.

And Mr Sommers said that, while he had been very pleased to read about positive results from other vaccines such as that developed by Pfizer, there was a special feeling about this one.

“It does feel a bit like I was supporting a team and it was good to watch other teams win and score, but now my team has won and I’m very happy about that,” he said.

Ms Hurst described the results as “promising” and noted that “the fact that it doesn’t need to be chilled at a very low temperature and is cheaper than the other vaccines will help in making it easier to distribute”.

But she added: “People have only been vaccinated for a few months so I would still want to know: what are going to be the results after a year? Is it going to be effective after a year?

“That’s something you really just have to wait for.”

In the research, a dosing pattern used by scientists suggested 90% effectiveness if one half dose was given followed by a further full dose.

Data showed 62% efficacy when two full doses were administered.