This outbreak is being called "the perfect storm." How did it start, what are the characteristics of the strain that's causing it and how much of a threat is it to global health?

Some 88 people have died from the highly contagious haemorrhagic fever in the DR Congo, with one death in Uganda, and at least 336 suspected cases.

At least 80 people have died in what the World Health Organization says potentially could be a "much larger outbreak than what is currently being detected and reported".