Similar to other commenters I enjoyed it but didn't really understand what the quarantine symbol did, and the wall building tool was very difficult to use. I'm not sure whether either of those were intentional.
But the core loop was very engaging. I had a few games there I won by within a few seconds. A few where it just spiraled and I lost quickly. And one game where I managed to wall off each outbreak as it came but could never quite stamp it out before a new outbreak happened somewhere else. Which felt ripped straight from the headlines. That alone means this game is quite a success. Well done!