VIRUS:

A program that infects a computer by attaching itself to another
program, and propagating itself when that program is executed.
A computer can become infected by files downloaded over a
network, or by the installation of new software or floppy disks that
are infected with viruses. Some viruses are only pranks, and perform
harmless actions like displaying a screen with a joke message
on it. Others can destroy files or wipe out a hard drive.

If one of us got it we all got it. Nothing much could be done
about it, except for taking us to the doctor and nursing us back to
health. But who took care of Mother? Illness became a method for
Mother to check out of the system. She wasn�t able to give herself
the time or care that she needed, so taking to bed was the only way
for her to escape the demands, isolation, and drudgery of life as a
housewife and mother.

(From the Cyborg Mommy User's Manual)