What Ebola drugs exist currently?

There a handful of Ebola drugs that have been shown to work well in animals.

One is ZMapp – the drug requested by the Liberian government to treat infected doctors. This contains a cocktail of antibodies that attack proteins on the surface of the virus.

Only one drug has moved onto early safety testing in humans. Known as TKM-Ebola this interrupts the genetic code of the virus and prevents it from making disease causing proteins.

TKM-Ebola was trialed in healthy volunteers at the beginning of 2014 but the American medicines regulator asked for further safety information. The manufacturer says human studies may soon resume.

Another option would be to use serum from individuals who have survived the virus – this is a part of the blood that may contain particles able to neutralize the virus.

Vaccines to protect against acquiring the Ebola disease have also been shown to work in primates.

The US authorities are considering fast-tracking their development and say they could be in use in 2016. Trials are likely to start soon, according to the World Health Organization.

However, experts warn ultimately the only way to be sure a drug or vaccine is effective is to see if it works in countries affected by Ebola.