well we all normally think that while using linux we don't need antivirus software !why--because there isn't any antivirus software for linux in market .but not too long ,there will be many (i guess)in a while .yes Currently there are under 100 native Linux viruses known
( http://zone-h.org/en/news/read/id=2567/ ) it appears that top virus writers have been working on linux security and they have been trying to create some viruses for linux OS they have succeded in their objective to an extant.These viruses may not infect the Linux computer but the user can easily attach and send these infected documents unknowingly to someone else and that is a serious problem.and still it is a nice starting point for virus writers and antivirus software developers.
THE RACE IS ONE!!!