Weird thing here, I use ClamXav on both my iMac and MacBook Air. ClamXav discovered the Flashback trojan file on both computers, yet the trojan hadn't spread (did the advised Terminal commands). To double check, I did defaults write com.apple.Finder AppleShowAllFiles TRUE and killed Finder, turns out it was hiding. I'd advise doing this too, to your Home folder.
4/6/12 at 6:28pm