This article is from the Fleas, Ticks, and Your Pet FAQ, by tittle@zmall.com (Cindy Tittle Moore) with numerous contributions by others.
Fleas can enter the home in many ways, even if your pet is not or only
rarely allowed outside. They can hop in from your yard, hitch a ride
on you, or even be left over from previous inhabitants (larvae can
remain dormant for astonishingly long periods of time under a variety
of conditions).
 
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