As of this moment:
Dallas County - 367 cases
Tarrant County - 100
Collin County - 88
Denton County - 83
https://txdshs.maps.arcgis.com/apps/opsdashboard/index.html#/ed483ecd702b4298ab01e8b9cafc8b83
Just heard on the news that Texas officials are concerned that Dallas will experience a big surge in cases because of infected people fleeing hotspots like New York, Connecticut and New Orleans. Looking for a link to confirm. But I don' t doubt it.