Excellent! Antivaxing bites back! I totally enjoy these cases of poetic justice when morons get to quickly suffer the consequences of their stupidity.
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Not entirely accurate. It disappeared mostly because the factors that contributed to its spreading were no longer existing.
The plague is carried by rats. The rats get bitten by fleas, which then become carriers as well. The fleas then bite humans, which are the...intended target.
Considering that personal hygiene became prevalent, as well as much lower contact with rats and fleas, AND the development of a treatment for the plague, it stands to no surprise that the Plague virus saw extreme difficulties in reproduction and spreading, up until the point where it's almost extinct. Almost.