It is highly unlikely that a virus would be able to use the boot blocks as a mechanism for spreading itself on either a floppy disk or hard disk.
However, a virus can change the information contained in the boot blocks and thereby cause problems. For floppy disks, a volume copy, using an application such as Apple's DiskCopy, from a "known good, virus-free" original replaces all sectors on the disk and eliminates the possibility of virus being on that disk.
Further, for either floppy disks or hard disks, any Macintosh virus detection application can scan and remove known viruses.
Article Change History:
1 April 1994 - Added references to Disk Copy, hard disks and virus detection software references.
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