|"the hard drive is not detected"|
Unlikely to be a virus. More likely to be a hard drive failure.
The error message you are getting is because the BIOS cannot detect a local bootable media and is attempting to boot via the LAN. That also fails because there is no boot device attached to the lan port
Does the laptop have a CDROM? do you have a bootable CD? You should download an ISO image for a bootable CD that contains hard drive diagnostic tools, boot to that and see if you can run some diagnostics on the hard drive. If the laptop BIOS does not even detect the drive this will be a wasted effort. Please confirm whether the drive is detected in BIOS. It is possible for bios to detect the drive but not boot to it if the bootsector has become corrupted.
Goin' Fishin' (Some day)