We have plague reports about our multitudes of prairie dogs here in South Dakota too. My 90 year old Dad (grew up on a farm in depression-era western Kansas) says the plague has always "plagued" the prairie dogs. Nothing new under the sun.
The first year we were in CO we lived near a large prairie dog community. Scared the bejeezus out of me the first time I heard them warning about the plague! It can be quite unsettling if your only experience with the plague is reading about the middle ages! LOL