First of all, it's a viral infection so antibiotics are useless. Second, smallpox is highly contagious. Anthrax isn't contagious. The situation is even more concerning than your source suggests. Smallpox vaccinations did stop in the US in 1972. However, if memory serves, the vaccinations weren't given until kids were about 6 years old. If that's true, then few people born after 1966 were vaccinated.

While the official pronouncement is that the only surviving smallpox samples are in carefully guarded labs in the US and Russia, there is evidence this isn't true. Quite frankly, I'm glad Clinton didn't destroy our smallpox stockpile like the WHO wanted (and that's rare praise of him coming from me.)