Wonderful concept, interesting gameplay, but...
A very smooth game, with a nice concept. I understand that it's using the same sort of framework as "League of Evil", and thus is limited in what you can do, but I thought it was a little disappointing that (aside from the Guards), the human hosts just sat around and waited to be used. I'd like to see a version of this game where the colonists, workers, administrators et al are walking around, doing their jobs. Where they react in fear if they see you, and try to run away. It would add a more interesting stealth element to the game.
This is also pushing the game beyond what it's presented as here (a puzzle platformer), but it would be nice to see levels laid out as though they were real working or living environments. Plotting a path to the target, infecting, using them, and reaching the exit would make the whole thing more strategic, and thus, more interesting.
But that would make it a rather different game from what you've presented, so let me just say, well done. I liked it.