Virus question

[Karen Donathan]

To Whom it may concern:

My name is Karen Donathan and I am a computer science teacher at George 
Washington High School in Charleston, WV.  We run our website 
(http://gwhs.kana.k12.wv.us) on a FreeBSD server.  This project was given 
to me, and I am afraid that I really should know more about how this 
works.

My question is as follows:  How can I run a virus scan on my system?  What 
scan do you recommend?

The reason I am asking this question is that our school system 
administrator just found that there were some files infected with Klez.h 
in the webroot directory of our server.  He found this out as he 
downloaded some files from this directory to our Windows-XP school server, 
and Norton flagged it right away.

Any suggestions?

Thank you,

Karen Donathan