A major coronavirus vaccine trial has been put on hold after a volunteer taking part in the UK fell ill.

The AstraZeneca-Oxford University vaccine is seen as a strong contender among dozens being developed globally in the fight against Covid-19.

Researchers say the pause is "routine" and happens when a participant becomes unwell with an "unexplained illness".

In recent months, the UK government has signed four deals with pharmaceutical companies for a different type of potential vaccine - and a total of 250 million doses.

So when will a coronavirus vaccine be ready? Who would get it first?

BBC health correspondent Laura Foster looks at the situation.

Graphics by Terry Saunders, producer Megan Fisher.