The World Health Organization has declared the latest Ebola outbreak an international emergency, as cases continue to rise in the Democratic Republic of Congo and neighbouring Uganda - including infections reported in the capital, Kampala.

The current outbreak is being driven by the Bundibugyo strain of Ebola, for which there are currently no approved vaccines or treatments. Fears are growing that this could escalate into a crisis on the scale of the devastating 2014 West Africa outbreak, which killed more than 11,000 people.

In this episode of The Fourcast, we ask how serious the threat really is, whether the world is better prepared than it was a decade ago, and what lessons were learned from previous epidemics. Krishnan Guru-Murthy is joined by Channel 4 News health editor Victoria MacDonald and Dr Oliver Johnson, who led an Ebola isolation unit in Sierra Leone during the 2014 outbreak.