Only two stockpiles — CDC Atlanta and the Soviets.
Civilization should do quite well if it ever got loose again and killed at it's normal rate ~ we'd end up with far more people than we had in the 1400s ~
There are even people with serious resistance to cholera, diptheria, typhoid, black death, and a number of other viral and bacterial diseases ~ there are also some downsides to that ~ But never mind.
Smallpox could be very bad. I was teaching a seminar for some of my Japanese students who were going overseas for home stays, and some of them were interested in why they had to get “ yellow cards” but others didn’t. I started to explain and suggest that vaccinations for things like meningococcus were good even for countries like the US. They got hung up on the word “vaccination”, so I showed them my smallpox scar. None of my students had one, and then I realized that almost no one has gotten one for almost 40 years.