Nimda Virus ruin my Network Softwares

I discovered a lot of eml files when I booted all my computers (I am working in a IT Institution)together with the 2 Outlook Window, I already reformatted all my hard drives and set all the shared drives to a READ-ONLY option, I discovered that Nimda virus is a worm, so as a result, it appear and appeared again and doing the same action: can’t open and save the work I do in the MS-Office, it suggested to save the file in a Rescued Document. I already downloaded a FIX TOOL at the SYMANTEC site. But still occurred again, can you recommend a good anti-virus for me? or a another precautions?

Thank and more power to all the good people in this site.

Jhet