A coronavirus vaccine might not be ready until later next year, the former deputy chief medical officer for England has said.

Professor Gina Radford said people needed to be “realistic” about the prospect of a vaccine as researchers are having to “start from scratch” to create one.

Foreign Secretary Dominic Raab also said a vaccine was unlikely to “come into play” until the end of this year.

It comes as the first human trials for a Covid-19 vaccine in the UK began on Thursday at the University of Oxford.

Prof Radford, who held her government role between 2015 and 2019, was asked on Sky News’ Sophy Ridge On Sunday show about the prospect of a vaccine.

She said: “We haven’t got a hugely good track record with vaccines for this particular virus, coronavirus, the family of viruses.

“But having said that, everything is being thrown at it. There are researchers all over the world trying to identify a vaccine.

“We have never seen anything like the effort that is being made to discover this vaccine.”

Prof Radford said there is a “huge process” of testing that needs to be undertaken to determine if potential vaccines are safe and effective.

“There is no point creating a vaccine that will then cause more harm than it is trying to prevent,” she added.

“I think those who are very used to the process of developing vaccines are saying they are not anticipating it being available until well into next year.”

Prof Radford said that while the vaccine could be created sooner as the Government is “fast-tracking” its development, it would still have to be manufactured in a large capacity.

Meanwhile, Mr Raab told BBC1’s The Andrew Marr Show on Sunday that the Government was “pursuing” vaccines and testing “at pace”.

He said: “But the vaccine wouldn’t realistically come into play until the end of the year – the testing, tracking and tracing I think has a better medium-term prognosis.”

Human trials on a potential vaccine saw the first two volunteers in the UK injected by researchers at the University of Oxford on Thursday.

Both participants – a scientist and a cancer researcher – said they wanted to help in what could be a groundbreaking development in the fight against the disease.

The Oxford Vaccine Group was hoping to repeat the process with six more volunteers on Saturday, moving to larger numbers on Monday.

Up to 1,102 participants will be recruited across multiple study sites in Oxford, Southampton, London and Bristol.