Neat game, you could improve the controls though. I made a similar game controls-wise and I struggled doing them as well..

Characters tend to flicker when they touch borders. Also, fleeing characters sometimes go through walls. I would have liked to be able to play the game in fullscreen mode. I like that you used time to create challenge!

Good game and nice concept but make that so people won`t glitch into walls

Nice concept, It can be improved because the game is quite difficult. Hard to make zombies bite the humans.