But what about Fort Detrick for god's sake???

OMG, I completely forgot about that iron-clad case!

As I continued to read on that MoA thread re recent cases, it seems some people point out that human populations in these areas are susceptible to plague since they were never subjected to them in Middle Ages like in Europe. The counter argument being that Mongols were likely bringing the plague into Europe (with steppe rodents) and would therefore be as non-susceptible as Europeans.

I remember reading about that most recent plague case in Mongolia because we were slap-bang in the middle of the covid pandemic.