What is Ebola, how does it spread and how do you catch it?
What is Ebola?
Ebola - or Ebola haemorrhagic fever (EHF) - is a really deadly virus: 50% to 90% of people who catch it die from it.
But there are a few forms of the virus which have been identified by scientists.
And given the right medical care and treatment, you can recover: American aid workers recover from Ebola .
Where has it come from?
Ebola was first spotted in the African countries of Sudan and the Democratic Republic of the Congo in 1976.
In the space of five months in that year, 284 people in Sudan caught the virus. It killed 117 of them.
How do you get it?
You can catch it through direct contact with the body fluids of an infected person such as blood and saliva.
It is not airborne like the flu so is more difficult to catch but is very infectious: so infected people have to be kept separate to reduce the risk of it spreading.
Healthcare workers who have looked after sick patients have also been infected.
What's it got to do with animals?
It's thought Ebola is carried by animals too - chimpanzees and monkeys have been badly affected by the virus.
It is spread to humans from close contact with infected animals and can then be passed between people.
This latest outbreak has been linked with fruit bats - which are considered a tasty meal in parts of Africa.
Is there a cure?
There is no cure or vaccine for Ebola but a new experimental drug, ZMapp, has been used in the US on health workers and a UK nurse who caught the disease in Africa. They recovered from the virus.
You lose a lot of fluids when you have the disease so giving people enough water and nutrition is one of the main treatments.