All reminding me of The Stand. And prairie dogs are said to spread it, and there is a vaccine for the "black" plague I think I remember my dad talking about having to get one. He is in the U.S military, they also have one for the Bird Flu. If you want the links for the sites send me a pm, I can't post links yet.
As already mentioned, smallpox has no animal reservoires. Also there were a number of other favourable aspects of smallpox that made it easier to eradicate (remember, in all this time smallpox is the only disease that has been, in effect, eradicated). To quote some points: Also, apes are a numerical too low population to have a large impact, moreover they have spread face to face, or in case of polio via feces (I think). One problem with polio is that its vaccine is a live one and can actually be transmitted from person to person. As such there is the possibility that the harmless strain used as vaccine might accumulate mutation and reverting it to a neurovirulent strain.
Plague is quite common in prairie dog populations. It is usually not a problem with the advent of antibiotics....
I think it is impossible. We have the medicine to be able to cure people of most plague-like diseases which use to ravage communities centuries ago. Moreover, if a plague does occur in some remote area, through technology and tried methods we can isolate the spread of the disease, minimizing the effect of it.
Yersinia pestis. Including some very common ones that are rather inexpensive, such as streptomycin and tetracycline.
