Scientists at the University of Oxford say they should have at least a million doses of a coronavirus vaccine by September this year.
They hope to have hundreds of millions of doses for use by the end of 2020.
However, it is still uncertain whether their jab will work as the first patients are not expected to take part in their trials until next week.
And the UK Business Secretary Alok Sharma said “we cannot put a date on when we will get a vaccine”.
Most argue it will take between 12 and 18 months before there is a vaccine that can be widely administered.
What is a coronavirus vaccine?
Vaccines train the immune system to prevent people developing a disease, such as Covid-19.
If enough people become immune then the coronavirus would not be able to spread so effectively and social distancing measures would no longer be necessary.
Approximately 80 groups around the world, including major pharmaceutical companies, are trying to develop a vaccine and some have already begun human trials.
This research is taking place at unprecedented speed – years of work are being condensed into months.
What have Oxford done?
The team at the University of Oxford had been preparing for an event like the Covid-19 pandemic before the current global outbreak.
They had already created a genetically engineered chimpanzee virus that would form the basis for the new vaccine.
They then combined it with parts of the new coronavirus.
The result is, hopefully, a safe virus that trains the immune system to fight Covid-19.
The big question is whether this experimental vaccine will actually work.
Prof Sarah Gilbert, the lead researcher developing the vaccine, says she is 80% sure it will work.
“This is my view, because I’ve worked with this technology a lot, and I’ve worked on the Mers-vaccine trials [another type of coronavirus], and I’ve seen what that can do.
“And, I think, it has a very strong chance of working.”
When will it be ready?
The team are already putting plans in place to mass produce the vaccine, even before they know whether it will work.
“The aim is to have at least a million doses by about September, once you know the vaccine efficacy results and then move even faster from there,” said Prof Adrian Hill, who runs the Jenner Institute at Oxford, .
“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 lead us out of lockdown.
He described a million doses as a “fairly modest target” and vaccines as “the exit strategy” for coronavirus.
When will we know the results?
The researchers hope to know if their vaccine is effective in the next few months.
However, the success of lockdown could prove a stumbling block, as if the number of coronavirus cases fall, then it will take longer to know whether the vaccine is effective.
There are discussions about whether it would be safe to deliberately infect people in order to get answers faster.
Will this really happen?
Sir Patrick Vallance, the UK government’s chief science advisor, said there was a need for realism.
“Just to put some realism on vaccine development, each single project does not have a high probability of success.
“So although everyone goes out with great enthusiasm and we hope they work, it’s never the case that you know you’ve got a vaccine that’s going to work.”
It remains the view of scientists advising the UK government and of the World Health Organization that 12-18 months is a more realistic timescale for a vaccine.
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