system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5 If the bubonic plague was present throughout so much of human history, why was the outbreak from 1346 to 1353 (the black death) so much worse than the other outbreaks?
gpt
It was able to quickly spread across all Europe (and probably north Africa too) though the Mediterranean trade network. A lack of hygiene and previous starvation also worsened the situation. Moreover, it's wasn't only the bubonic plague, there was also its pneumonic form, which is much more contagious and deadly.