it dipends of the type of virus. some virus require reboot of machine in order to remove them, but the other one doesn't.
S
S.Net
Inside Technologies
MVP System Center Cloud and Datacenter Management
MCITP Enterprise Administrator
MCTS Server Virtualization - Operations Manager 2007 - Exchange Server 2007 - MCSE-M
S.Net Blog
WindowServer.it
WindowServer.it Learning Portal