svchost.exe (usb or other drives)

If you see a file in ya usb flash that's called svchost it's 100% a virus even if you delete it it will come back,so u would need to follow these manual steps to remove and prevent it to copy itself in ya usb drives:
go to start click run than cmd to open the command prompt do this with ya usb plugged
before u follow the nexy steos do this, open a note pad or write in ya browser: md svchost.exe and copy it....

type in command promt cd\ than enter
type f: than enter ( you can do so with e g etc)
type attrib svchost.exe -s -h -r -a than enter
type del svchost.exe note that you need to be very quik on the next step or the virus copy itself back
right click and paste md svchost.exe right after you delete it so it can't copy it's self back in ya drive, repeat this with ya other drives to remove the virus

Note to see the svchost.exe u need to enable view hidden files or go to command prompt type in the drive you want to check and type in dir /ah to view hidden files.