Seig Heil!! </sarcasm>
Why would the damage be minimal? Smallpox was stopped by vaccinating people against it. However, the virus would have a large supply of hosts now because of the generations of people who haven't received vaccinations. If dispersed effectively, it seems like smallpox could do a lot of damage.
Not as much damage as the humans it might wipe out. Just sayin'.
panic: kernel trap (ignored)