I'm sorry but-
The black death killed more people bc It is still alive and thriving killing more people as I type this message. and when the black death was in its prime it killed >1/3 of Europe's population (~500mil people), in todays time would be more than half of our current population. Smallpox however only killed ~172mil people in its prime. Also smallpox was eradicated and a mandatory vaccine was created so therefore the black death is worse than smallpox