Really awesome submission. The presentation is top notch considering the length of the jam and I thought the way the curse could spread through the population you were protecting if you weren't careful.
I guess my only real critical feedback would be that I think being able to hold down a button to shoot continuously and having the shooting direction be independent of the player movement would be a good change in my opinion (example: wasd controls movement, arrow keys fire continuously in whatever direction pressed). I might only be saying that because I struggled with the difficulty though, so take that suggestion with a grain of salt.