Louis Pasteur had an effective rabies vaccine in 1885, without even being able to see the vaccine (no electron microscope.)
So why don’t we have an Ebola vaccine?
Possibly, Africa is incapable of 19th century Western science.
Possibly, the West never found it economically worthwhile to create an Ebola vaccine, given that it only sickened a few Africans, that making vaccines has become ridiculously expensive because of safety and liability issues, and that every time the West pushes a vaccination campaign in the Third World it is accused of infecting people with AIDS or sterilizing them.
Or possibly, Ebola is really hard to turn into a vaccine.
There was griping from medical professionals that no one in the west cared about Ebola until it became really bad. And this last out break was the worst.
Hopefully, they get it under control and eradicate it.