Sure, if they aren't symptomatic they aren't contagious, but how can one be sure in the period when someone is sort of starting to feel a little warm, not feverish, I'll be fine after a good night's sleep, no, I don't need to take a day off . . . . You know, the sort of person who can cripple a whole office with a cold or flu? Sure, it's easier to catch the flu, but a lot less likely to die horribly of it.
Incorrect. Even in an average year about 36,000 people die of flu, So far ebola has only killed about 5,000 in Africa and a negligable number everywhere else.