Run an antivirus scan in your system. Use Immunet Plus, Norton, Kaspersky, Bitdefender, Avast or any other antivirus software to scan your system completely and automatic removal of virus. Once system scan is completed and virus is removed, use system restores to remove recent updates in your system. Virus will be removed, if it had come with any download or installation.
According to Microsoft: “svchost.exe is a generic host process name for services that run from dynamic-link libraries”. In the Windows NT family of operating systems, svchost.exe (Service Host, or SvcHost) is a system process which hosts multiple Windows services.
svchost.exe runs in multiple instances in task manager...
Try to disable the items that run under Startup Tab in msconfig. (Do not disable any Microsoft processes).
Check which process takes up more CPU or Memory. If you find any, search for that process name in google . It could still be a virus like activity.
Alternately, check if your Anti Virus program is doing any Idle time scans.. It does happen a lot if you use Norton Anti Virus. All the best.