LogFAQs > #979368712

Bubonic plague is still around. Mutations against it have been identified in London and Denmark --- I presume from remains.

https://www.npr.org/sections/goatsandsoda/2024/02/14/1231215446/so-you-think-you-know-all-about-the-plague
When a flea itself is infected, the plague bacteria live inside the insect's gut. There, the bacteria create a gooey, sticky material, called a biofilm. This film forms a little plug in the flea's throat, making it hard for the insect to swallow. So when the flea bites an animal, instead of swallowing the animal's blood, the flea essentially vomits the biofilm along with the plague bacteria into the animal's blood."
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