Serum made from the blood of recovered Ebola patients could be available within weeks in Liberia, one of the country’s worst hit by the virus, says the World Health Organization.

Speaking in Geneva, Dr Marie Paule Kieny said work was also advancing quickly to get drugs and a vaccine ready for January 2015.

The Ebola outbreak has already killed more than 4,500 people.

Most of the deaths have been in Guinea, Liberia and Sierra Leone.

Dr Kieny, WHO assistant director general for health system and innovation, said: “There are partnerships which are starting to be put in place to have capacity in the three countries to safely extract plasma and make preparation that can be used for the treatment of infective patients.

“The partnership which is moving the quickest will be in Liberia where we hope that in the coming weeks there will be facilities set up to collect the blood, treat the blood and be able to process it for use.”

It is still unclear how much will become available and whether it could meet demand.

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Serum

If a person has successfully fought off the infection, it means their body has learned how to combat the virus and they will have antibodies in their blood that can attack Ebola.

Doctors can then take a sample of their blood and turn it into serum – by removing the red blood cells but keeping the important antibodies – which can be used to treat other patients.

The Spanish nurse who became the first person to contract Ebola outside West Africa tested negative for the virus after reportedly receiving human serum containing antibodies from Ebola survivors.

Dr Kieny said the treatment was not without risks, and WHO has already issued guidelines to ensure safety. Any donor blood will need to be screened for infections such a hepatitis and HIV, for example.