"There is a real opportunity that a blood derived product can be used now and this can be very effective in terms of treating patients,” Dr. Marie Paule Kieny, the agency’s assistant director general, said at a press briefing today.
The idea is not as bizarre as it might sound. A viral infection triggers an immune response – an attack by the body against its microscopic intruder in the form of antibodies. Those antibodies block the virus from infecting new cells, and they linger in the blood long after the infection.
Dr. Kent Brantly, an American aid worker infected while working with a missionary group in Liberia, reportedly received a blood transfusion from a child who survived the virus. He also received the experimental drug ZMapp, which is a cocktail of three synthetic antibodies designed to mimic an immune response. No one knows what role – if any – the treatments played in Brantly’s recovery.
There is evidence, however, that antibodies against Ebola linger in the blood of survivors. A 2009 study of blood samples collected during three Ebola outbreaks in Gabon found that levels peaked 30 days after exposure and “declined slowly over several years.” But not all antibodies are created equal, according to Thomas Geisbert, a virologist studying Ebola at the University of Texas Medical Branch in Galveston, Texas.
“It’s possible that some people have antibodies that are directed against more important parts of the virus in terms of slowing it down. It could vary from person to person,” he said, explaining how different antibodies hone in on different parts of the sly virus. “In an outbreak scenario, it may difficult to identify who the best donors would be. It would have to be studied in a lab.”
And that’s what WHO officials intend to do, explaining that such studies in West Africa “should be based on the aim to learn as much as we can as fast as we can without compromising patient care or health worker safety."