I played this the first time yesterday in a 4-player game.
And we had such a blast. It had a Mafia feel, but without Player Elimination and more paranoia. The forced card exchange is such a great mechanic. In Mafia the game begins very slowly with RVS and such, but even with the first card exchange you get nearly a cardiac arrest. We made some rule errors with the Parasites in the first game, which basically made it easier for us, but it didn't matter. The host could infect us all. The body scan is a great item. All immediately wanted to play a second game and this time with bonus cards and (hopefully) correct ruling. The host was the same one and couldn't infect any of us. We figured that out and tried to avoid him. Just before we won, I healed him for a group win.
The biggest point of criticism was that the item cards don't have text on them (I assume this is like that so it can be distributed language independant). So basically every time someone drew a card he had to look the function up in the Card List Sheet. And that was especially problematic if you read the back where the stronger items are listed what everybody could see. This slowed the first games down way too much, but with more experience, this isn't much of a problem, I assume. And I think it might even better with 6 players.
I also think this could work as a Forum Game. But I like to play and not to moderate.