Flea larvae don’t live on dogs or cats. Nor do they bite pets as a source of nutrition. Flea larvae are free-living (not parasitic) and develop off the host.
Eggs Fall from Hosts
Female fleas deposit eggs in the fur of their host. However, once dried, the eggs readily fall off of the animal. In one study, 60% of the eggs dropped off within two hours of being laid. Only 2.3% of the eggs remained on the host by the 8th hour.
Larvae Develop & Feed Off-Host
Flea eggs get distributed in the environment based off of the infested pet’s movement range and grooming habits. When the eggs hatch, the larvae the develop and feed in the environment. Cat flea larvae are free-living scavengers. They don’t feed on blood directly from the animal.
If cats or dogs have dense or soiled fur, then flea eggs may get lodged in the haircoat. In these rare cases, providing the eggs survive long enough, flea larvae may hatch on pets.