Fleas

Contact: Eric Day, Manager, Insect Identification Laboratory

Publication 444-257, August 1996

Fleas

SIZE: 1/8 inch (3mm)

COLOR: Very dark

DESCRIPTION: Adult fleas are about 1/8 inch long, wingless, and have three pairs of legs. The hind pair of legs is modified for jumping. Fleas are vertically flat like a fish, and can move easily through the hair of a host. The immature stage or larval stage of the flea looks like a small white worm with a dark head. Flea eggs are small and white.

HABITAT: The cooler and drier fall weather brings a reduction in the number of household fleas. However, house pets usually maintain small flea populations throughout the winter, with the numbers increasing slowly in the spring and exploding in mid-to-late summer.

LIFE CYCLE: Female fleas lay eggs loosely in the host's hair (usually a cat or dog). The eggs drop off and hatch into tiny, hairy, worm-like larvae. The larvae are usually found where the animal sleeps, along baseboards, in carpets, or on furniture. Larvae pupate and new adults emerge. The new adults seek a host immediately and must get a blood meal to survive and produce eggs.

TYPE OF DAMAGE: They will bite humans-especially when they cannot find their usual animal host or if they become very numerous. Their bite often will leave a small, red, irritated area on humans.

CONTROL: The key to successful household flea control is frequent vacuuming of pet bedding and resting areas, treatment of the pet, and careful use of insecticides.

INTERESTING FACTS: Fleas are not known to be capable of transmitting infectious diseases in Virginia; however, allergic reactions to flea bites cause the most complaints.

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