Okay... after some research, I concluded that 1) I don't know what I'm dealing with, and 2) since the damn thing can elude two of the best antivirus around, there is no chance to get rid of it without characterizing it before... So, I must locate a file that is infected FOR SURE. There are a few companies out there (Kaspersky and others) to which a virus can be delivered for characterization. At that point, once the thing has a name, it could be easier to find the appropriate tool.
In your opinion, what kind of "bait" could I use, and how, in order to get hold of an infected file?...