The Covid-19 vaccine trial in Oxford has been placed on hold due to an 'unexplained illness', pharmaceutical company AstraZeneca has confirmed.

We've put together everything we know so far about this latest update.

What have AstraZeneca said?

AstraZeneca are working with the University of Oxford on developing a coronavirus vaccine.

In a statement on Tuesday (September 8), AstraZeneca said: "Our standard review process was triggered and we voluntarily paused vaccination to allow review of safety data by an independent committee.

"This is a routine action which has to happen whenever there is a potentially unexplained illness in one of the trials, while it is investigated, ensuring we maintain the integrity of the trials.

"In large trials illnesses will happen by chance but must be independently reviewed to check this carefully.

"We are working to expedite the review of the single event to minimize any potential impact on the trial timeline.

"We are committed to the safety of our participants and the highest standards of conduct in our trials."

No further details have been provided to explain what triggered the pause of the trial.

Over in the United States, AstraZeneca began its phase three clinical trials last week. According to NBC News, trial sites in the U.S. have also been impacted by the pause.

What is the Oxford vaccine?

The Oxford vaccine uses a type of virus called 'adenovirus' to teach the immune system how to make antibodies to attack the coronavirus's so-called spike protein. That spike protein allows the virus to infect human cells.

No further information has been released by AstraZeneca or the University of Oxford at this stage.