I think you should volunteer to work on her bike as an experiment. Get her to ride it on a trainer first so the top of the frame is nice and salty. And make sure you put your face right down into the saddle when leaning over to tighten the rear QR, as maybe ass-sweat has a different level of contagion than head sweat.
If you don't get sick (and she actuall has Ebola, which is super unlikely and only a complete ignoramous would actually worry) then obviously bicycles are not vectors for the disease.
If you do contract ebola and die, meh, no big loss.