Image copyright Reuters Final clinical trials for a coronavirus vaccine, developed by AstraZeneca and Oxford University, have been put on hold after a participant had an adverse reaction in the UK.
AstraZeneca described it as a "routine" pause in the case of "an unexplained illness".
The outcome of vaccine trials is being closely watched around the world.
The AstraZeneca-Oxford University vaccine is seen as a strong contender among dozens being developed globally.