It is an extremely rare and lethal haemorrhagic fever, closely related to Ebola, for which there is no known cure.

ECONOMIST: There are few worse viruses than Marburg

The severe form of the disease, dengue haemorrhagic fever, involves a high temperature, head and muscle aches, internal bleeding and, at worst, circulatory failure.

ECONOMIST: Dengue fever, a man-made disease

Within hours he was diagnosed with Crimean-Congo Haemorrhagic Fever, a virus nasty enough for him to be put onto a military transport aircraft for transfer to an isolation hospital in London.

ECONOMIST: Where and when will the next pandemic emerge?