Re: I thought this one was fairly clear to be "proper" plague
Not quite; the Athenian epidemic of 430 BC described by Thucydides, who contracted it himself, was likely Ebola.
Which is my exact point - all historical books call it plague. The only 3 pandemic diseases which get a honourable mentioning in historic literature are Plague, SmallPox and Cholera. Anything that does not look like classic SmallPox or Cholera (f.e. even the haemorrhagic aka "purple" form of Smallpox) is called Plague. So if once upon a time there was an Ebola epidemic in Europe (as suggested here) it would have gone down as plague in the history books. Similarly, most medieval pandemics of dysentery, etc have been written down as Cholera.