Datasets Found:
Respiratory Disease Mortality Rates by County Annual Timestep
Cardiovascular Disease Mortality Rates by County Annual Timestep
Infectious Disease Mortality Rates by County Annual Timestep
Air Quality By County Annual Timestep from EPA AirData
The Air Quality datasets were seperate zipped csv files for every year between 1980 and 2014. There is a script for extracting all of the air quality data here