[Ruatha]

Originally posted by BBegemott:
Various viruses like to infect svchost.exe. If you see a lot of those proceses and notice significant decrese of your PC performance, you might have got a worm. I recently had one named W32.HLLW.Gfaobot.DK. It exploits some windows vulnerabilities while spreading in LAN and sends lots of spam, which causes internet connection to lag.

Usually they don't "infect" svchost.
They make a new executable somewhere else and starts that.
See the second link in my previous post.