"Conceal their point of origin"? How?
People from those West African countries would be traveling on their home country passports. That cannot be concealed.
Considering how often you guys complain about illegal immigration you should know that it's most certainly possible to enter the US without a passport.
Denying entry to those with actual passports would simply encourage people to use other, untraceable ways, which they would obviously do. It happens all the time. (this is also why the right's opposition to guest worker programs with Mexico never made any sense)
The CDC director's letter on this pretty much covers it:
http://blogs.cdc.gov/cdcdirector/2014/10/06/letter-to-the-editor-of-the-financial-times/
So unless you guys who constantly complain how porous our border is suddenly have decided that our borders are impregnable, a travel ban is a dumb, dumb, dumb idea. Having someone's origin concealed is the worst possible thing we could do.
People from those West African countries would be travel here on visa's we issued them. That would also show their port/country of origin. That cannot be concealed.
It most certainly would not if they traveled through a third country.
People from other countries who happened to travel through those West African countries would have had their passports stamped. We would therefore know they visited there etc. That cannot be concealed. (Disclaimer: I checked some of those countries to ensure they do the usual passport stamping, but not all.)
I'm going to guess you haven't actually visited any of these countries. Not only can passport stamping be concealed, many of these countries don't even bother. What a country claims they do and what a country actually does are two totally different things.
I still think the best course of action is to contain the outbreak to its country/point of origin and send in people and supplies to contain or eradicate it. Allowing it to escape was stupid.
Fern
There was no way we could ever have prevented its escape with an outbreak this large. Previous outbreaks have always been in geographically isolated areas with largely immobile populations. So replace "stupid" with "probably inevitable".