Linux doesn't really need anti-virus due to the way its security is laid out (viruses really can only affect files that are writeable by the same user/group as the file that is infected. However, there are a few Linux viruses. That being said, I have never been infected by one in the 13+ years I've been using Linux, nor have I ever meet anyone who had. There is anti-virus software for Linux, and I do recommend that you run it if only so you don't hold a virus in one of your files that then gets transferred to a Windows machine. Check out http://www.clamav.com/
or if you may be able to just install it with yum/apt-get or whichever installer you use.