How can it not be all over Lakewood when half the town was at ECAP?
If, indeed, someone were infected by 2/18/20, that would have been three weeks ago. It could be that there are one week old cases walking around without major symptoms yet (but still spreading it to to others). Additionally, that was in the very early stages in the US. People who were exposed were probably not exposed continually to multiple persons. Their immune system wasn't repeatedly bombarded with new exposures like what happens when around larger numbers of infected people.
STAY AWAY FROM CROWDS and even GROUPS.