Ebola

[planetdoc]

Aid organisation Doctors Without Borders says an Ebola outbreak suspected of killing at least 78 people in Guinea is an "unprecedented epidemic".
excerpt

has spread across the west African nation.

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Another article says

The WHO says 83 people in Guinea have died in suspected cases of Ebola, which is spread by close contact and kills between 25% and 90% of its victims. It has now spread to neighbouring Liberia, as well as Guinea's capital, Conakry, which has a population of two million people. Sierra Leone has also reported five suspected cases, none of which have yet been confirmed, while Senegal, which also borders Guinea, has closed its land border.

So we know that Ebola has a high mortality rate. The hemoragic fever (people bleed to death) usually kills so quickly that the spread is limited in the rural areas affected. In this instance Ebola cases have been found within large populations spread over large geographic areas. Previously Ebola transmission was via contact with bodily fluids (diarhea, vomit) of an affected person.

Recent research has found

Recent research In late 2012, Canadian scientists discovered that the deadliest form of the virus could be transmitted by air between species. They managed to prove that the virus was transmitted from pigs to monkeys without any direct contact between them, leading to fears that airborne transmission could be contributing to the wider spread of the disease in parts of Africa.

airborne transmission greatly increases virility of the disease. Ebola has no known cure.