Biology:
Female's lay 4-8 eggs after each blood meal, laying some 400-500 eggs during their lifetime. The eggs are not glued or stuck to the hairs or body but are deposited on or between hairs, or in the nest or bedding material. Hence, eggs are deposited on the animal either fall or are shaken off, and are frequently found in cracks and crevices where pets sleep or frequent. Adults usually begin to seek a blood meal on the second day of emergence, but can live for several months on stored body fat. Although they have a preferred host, they will readily bite and can survive using other species as hosts..

Habits:
It is not necessary to have pets in the building to have fleas present. Since fleas can jump 6" or more vertically, they can easily hitch a ride on trousers and shoes etc. if a building has been vacant for some time they are often greeted and attacked by fleas. This can happen even if a building has been vacant of animals and humans for as long as 6 months or so. This can happen because of the potentially long pupa period, and adults can live so long without food.

Reasons for Control:
Loss of goodwill, bad publicity, prevention of disease, annoyance, harmful to pets, loss of quality.