Obama attempted to calm public fears regarding Ebola in his last weekly address. But if Obama perceives there is panic among the uninformed, then he should inform THEM--not whoever it is that listens to weekly presidential addresses.
The most appropriate intervention for a POTUS in this instance is to have the Surgeon General speak to the public about Ebola, like C. Everett Koop did for AIDS in the 1980s. But Obama doesn't have one, because the GOP Congress has held up his Surgeon General nominee for a year because he thinks gun violence is a health issue. (It is, btw.) So I think he should call for a brief primetime address to the nation to dispense the necessary information--some medical facts, an explanation for the lapses that have occurred thus far, and reassurance to the public that we are on this problem. He should then explain why he is doing this himself--and call on the public to persuade Congress to move forward with the nomination NOW, likening it to going to war without a Secretary of Defense.
But Obama doesn't do this sort of thing, evidently because he doesn't want or know how to use his anger to connect with the public. As my mentor Johnny Rotten once observed, "Anger is an energy". Obama doesn't seem to believe that. And I believe this has hampered his ability to connect to a distressed public throughout his presidency--including many of us loyal Democrats.