UK volunteers could be given the first dose of a potential coronavirus vaccine within the next week, researchers say.
Experts at the University of Oxford are working hard to develop a vaccine that could prevent people from getting Covid-19.
They hope to have a candidate ready for clinical trials soon, and as part of their preparations the team aims to have at least a million doses available by about September.
Sarah Gilbert, a professor of vaccinology at Oxford University, who is leading the team said a vaccine could be available for use by the general public by the autumn.
However, she said there is always an unknown and scientists can never be sure that vaccines are going to work.
Prof Gilbert explained previous comments in which she said she was 80% confident of the vaccine's success.
She said: "Personally, I have a high degree of confidence.
"This is my view, because I've worked with this technology a lot, and I've worked on the Mers vaccine trials, and I've seen what that can do.
"And, I think, it has a very strong chance of working."
Asked when the first dose of the vaccine might be delivered to a trial volunteer, Professor Andrew Pollard, chief Investigator on the study said it depended on when the last part of the testing from the manufacturing had concluded.
However, he added: "But it should be within the next week or so, but we'll confirm that as soon as we can."
The researchers say that, as well as developing a vaccine that can be used on a mass scale, it is important to make sure it can be manufactured at the required pace.
Professor Adrian Hill, director of the Jenner Institute at the university, said the team probably has the "most ambitious scale up" programme of all the groups working on a vaccine.
He added: "We're now moving to the point where instead of doing maybe a three litre manufacturing run, we're up to 50 litres will go to 100, 200, maybe even 2000.
"And we're talking to manufacturers who can provide that sort of manufacturing service.
"The aim is to have at least a million doses by around about September, once you know the vaccine efficacy results.
"And then move even faster from there because it's pretty clear the world is going to need hundreds of millions of doses, ideally by the end of this year to end this pandemic, to let us out of lockdown.
"A vaccine is the exit strategy for this pandemic and then we're very likely to need a vaccine in future years because it's unlikely we'll be able to eradicate this virus."
