“...since the Plague struck Europe in 1348”
That was due to global warming.
The plague was also due to rats....or the flea’s that they carried....ironic
Three conjectures on underlying causes of Plague in Europe in 1348.
The Little Ice Age began in 1315 and the colder, wetter weather and famine was stressful to the rats and the fleas jumped off them looking for a better meal.
A germ that affected the fleas feeding mechanism and left them unable to digest their meals, was able to affect the fleas more in the Little Ice Age; and the ‘starving’ fleas jumped off the rats trying to find a better meal.
Bamboo dies off in great swaths every 80-100 years or so before regenerating and the rats that live in the groves then vacate it looking for sustenance, taking their fleas with them. Multiple species of bamboo may have coincidentally died off in Asia around the same time and thus the rats left migrating West to Europe, taking their infected fleas with them.