Suuuure, re-breathing air through a greasy snot rag is good for you. Kinda' like wearing a diaper and using its contents to prepare your food.

A possibility is that areas with mask mandates are also encouraging more testing. With high Ct thresholds in the PCR test, more testing just means more false positives.

You'd need to check for confounding variables such as above, also demographics, ethnic makeup and climate could play a part.