Limewire is a p2p client which connects users to the Gnutella Network, which is an open network, decentralized and not dependent on any website.
There are viruses .. yes .. but not from LW itself. They are shared on the network by users appearing to be members like youself.
All you and other users, can do is be extra wary, learn what are likely to be a viruses and avoid them at all costs.
Scan Everything with your AV Program Before opening.
When Searching Video Files Always use Bitzi. See Instructions Below.
After you have completed your search, Right click on the file that you're interested in. Now go to Advanced > Lookup File With Bitzi. Left click on that and a new browser window will open which is Bitzi. Now you will see how other members have rated this file. If you see something like "Bitprint not found" then Leave it alone. Its probably a Fake or Corrupt File. If it has been Rated then you can read what or how the members feel about the file.
Hope this Helps.