I hope this is not too much of a silly question, but here it is.

I have read several reports that one of the Doctors who survived Ebola donated his blood so that the plasma (which contains anti-Ebola antibodies) can be extracted and was used to treat other patients. I have been wondering about this for the past week or so.

If this is actually an effective treatment (is it?), then would it not make sense to collect blood from Ebola survivors in Africa (perhaps paying for it as is done in many blood donation centers), extract the plasma, and use it to treat the Ebola patients?

I expect there would be many practical problems in implementing such a plan, but IMO it seems a potentially useful treatment resource is being ignored. What am I missing or not understanding?