Why Ebola Is So Dangerous

The World Health Organization (WHO) says it is taking "very seriously" the current outbreak of the Ebola virus in West Africa. Out of 122 cases recorded in Guinea so far, at least 80 patients have died, with a further four deaths in Liberia.

What is Ebola?

Ebola is a viral illness whose initial symptoms can include a sudden fever, intense weakness, muscle pain and a sore throat, according to the World Health Organization. And that is just the beginning: the next stage is vomiting, diarrhoea and - in some cases - both internal and external bleeding.

The disease infects humans through close contact with infected animals, including chimpanzees, fruit bats and forest antelope. It then spreads from one person to another: by direct contact with infected blood, bodily fluids or organs, or indirectly through contact with contaminated environments. Even funerals of Ebola victims can be a risk, if mourners have direct contact with the body of the deceased.

The incubation period can last from two days to three weeks, and diagnosis is difficult. The human disease has so far been mostly limited to Africa, although one strain has cropped up in the Philippines...