Actual size: 0.06 in.
There are over two thousand different species of fleas. The cat flea (Ctenocephalides
felis) is the most common flea found in homes and on pets. Despite its name, the
cat flea is not specific to cats. It is also a common nuisance to dogs and other
domestic animals. Cat fleas will bite almost all warm-blooded animals, but they
cannot survive long enough to reproduce unless they find a suitable host.
The Flea Life Cycle
The common flea can be one of the most frustrating pests to remove. Their tiny size,
incredible reproductive rate, extraordinary jumping power, and wide range of habitats
make fleas a stubborn and troublesome pestespecially for pet owners. Understanding
the life cycle of a flea will help you eliminate fleas from your pets and your home.
A flea develops from egg to adult in as little as two weeks. Where environmental
conditions are not ideal, this life cycle can span over five months. Even in colder
climates, fleas commonly survive the winter protected by their impenetrable cocoons.
Learn more about each stage of the flea life cycle:
Once an adult female flea has arrived on a suitable host, it will remain there for
the rest of its life, producing an average of five eggs per day and 150 to 800 eggs
in its lifetime. When the eggs are laid, they fall off the host animal and land
in the areas where the animal spends most of its time. The most common area for
these eggs to land and accumulate is deep in the fibers of carpets, cracks in the
floors, and crevices in couches.
Larvae that hatch from the eggs rely on high-protein food for their survival. The
source of this protein is usually the dried feces of the adult flea. This protein
will fall off of the host animal and will follow the same path as the eggs, providing
the emerging larvae with a ready source of nourishment. The larvae hatch as small,
legless, worm-like insects.
The larvae spin a cocoon and transform into pupae. Host animals moving near the
cocoon can provide the stimulus (vibration and heat) needed to trigger the adult
flea out of its cocoon. Without the proper stimuli, fleas can survive inside the
cocoon for up to five months. When fleas are in their protective cocoons, they can
also survive most flea treatments, which means they can re-infest pets. That's why
it is so important to do a follow-up treatment two weeks after the first treatment.
The flea uses visual and thermal cues to locate a host, which must be found within
about a week, or the flea will die of starvation or desiccation.
The adult flea emerges from the pupa, but it may remain in the cocoon until it receives
the necessary stimulation to emerge and seek a suitable host. Once adult fleas find
a host; they mate and begin the life cycle all over again.
Fleas are found throughout most of the United States and are prevalent when temperatures
are between 55°F and 90°F with a relative humidity of 50 percent. In southern
states, the flea season lasts year-round and peaks over the summer months. In temperate
climates, the height of flea season occurs between August and September.
Fleabite Allergy Dermatitis
About 20 percent of cats and dogs that are infested by fleas contract Fleabite Allergy
Dermatitis (FAD). Thinning and loss of hair in a triangular area above the tail
is the first indication that an animal has FAD. Scratching and biting soon lead
to the hair falling off on various parts of the body, followed by the oozing of
tissue fluid, and finally, secondary bacterial infection. Upon achieving complete
flea control, and in conjunction with an appropriate treatment, the animal will
grow its hair back.
Fleas may also serve as an intermediate host for the dog tapeworm (Diplyidium caninum)
which infests dogs, cats, and occasionally, small children. An estimated 30 percent
of all domesticated dogs carry the dog tapeworm parasite. While these worms are
generally harmless to healthy dogs, their presence can be alarming to the pet owner.
Tapeworms are treatable by a veterinarian. Bubonic plague and murine typhus can
also be transmitted by fleas, but are more commonly transmitted by other flea species,
which are associated with rats and other small outdoor mammals.