Backups, backups, backups!
Once upon a time, backups were taken seriously.
OK, so that was only a long, long time ago, in a galaxy far, far away. But some of us in this galaxy, on this very planet, did take it seriously. And ya know what? Backups work!
This really isn't about a trojan or virus or whatever, it's about a failure to properly back up data. Imagine for a moment that, instead of stealthy malware encrypting all it finds, utility workers outside crossed the lines, and fried everything on the circuits. Instead of 120V on the line, imagine that it was briefly touched with 480V. (That actually happened to some people I knew.) Now, instead of taunting messages, the equipment is fried to a crisp. Time to replace everything.
If proper backups have been done, then you replace the machine, grab last week's tape and last night's diff, and restore everything. Done. Or in the article's case, isolate the malware, flatten everything, and restore from tape.
Oh, did I mention tape? Yes, that's always good and needed. Funny how backup software works best with tape. Lots and lots of cheap tape, cartridge after cartridge, no problems. Backup software doesn't work so well with anything else, despite what's claimed on the package.
And that brings up something else: Keep your scanners up to date!! Enforce virus scanners for all machines in the organization. Not only the definitions, but also the engines.
Face it, they are out to get you, so it isn't paranoia, it's normal and reasonable precautions and defense.