While the situation in Africa is horrible, the media has way overblown what it might do to the US or Canada. Both countries, while large, are equipped to prevent such outbreaks.
Keep in mind that just about every year, we have some new, terrible epidemic that will end America. ie. Bird flu, SARS, MRCA, Swine Flu (I got that one and survived just fine), and before that things like AIDS and what not. Point is, the media absolutely loves scaring you. That is why minor weather events like 2 inches of snow in a southern state gets insane coverage. People get scared and watch, meaning they see more ads. Works the same way with this. The media is going to try and scare everyone into watching using "expert analysis" to scare you thus making them more money.
The west will be fine.