Plague is common in New Mexico in summer, partly due to prairie dog colonies near large population areas. Friends who work for the health department and trap rodents to test for the plague refer to NM as the “land of the flea and the home of the plague.”
Yikes 😳
I have read in the past that 17 western US states have endemic bubonic plague. Half a dozen or so people a year die or are very sick from this illness here. A problem for Europe in the Middle Ages was that while the common Norway rat is mostly a cellar dweller, the Black rat which was carrying in bubonic infected fleas was an upstairs rat, thus exposing more people to the fleas.
I am currently rereading an old book, copywrite 1966, called “My Way Was North, written about wildlife in our far north areas. The book pointed out there is a roughly 10 year cycles of gradual increase of rodents/rabbits to huge quantities, and then a sudden die off to almost no rabbits or the many predators (animal and bird) that live off them. Then the same gradual increase again. It was suggested this might relate to the approximate 11 year sun spot cycle of increase and decrease in number of sun spots.