Jeff, I did some additional research on this and it appears to have been a very old Windows-only trojan going back to 2001. This means that virtually all anti-virus software would be quite capable of thwarting any damage. And that Mac and Vista systems could not be affected. The official "threat assessment" for this is "low", based on it's low level of distribution and it's easy removal. Nonetheless, it serves as a reminder that anti-virus software should be current and that standard precautions should always be taken. And, of course, everyone should make regular backups of their computer, both to protect from malware and also from inevitable hard drive failures.
Laurence