Great jam entry! I like the counter of the amount of infected. I don't quite know why, it just really adds to the fun of the game seeing your impact on the infection.
I think the gameplay gets a little bit repetitive at some point. Just because I was curious I kept playing until infected hit 0. After that there were still more zombies even after the counter hit zero, the next time you switch levels the game crashes.
Another thing that hampered the fun a bit is it was hard to discern the difference between walls and paths, because they are both flat. Early in the game I spent some levels running circles because the way I needed to go looked like a wall.
The art looks good, the mood is funny. All in all I like it.