Bloodhound is a Visual Basic worm that spreads via e-mail attachments through Outlook and peer-to-peer file sharing networks. The subject line will refer to "freedom of expression" or indicate that the body/attachment contains a legal notice of some sort. The message will have various attachment names and extensions. Bloodhound/Fili infects all Windows versions except 3.x, but not UNIX/Linux or Macintosh systems. Upon activation the initial version of this worm will block some anti-virus processes (not Norton/Symantec) and compromise other security applications.
If you use Norton AV check this out also:
http://www.symantec.com/avcenter/ven...loodhound.html