Back to Client Info Index

Fleas and Flea Control

What are fleas?

Fleas are insects that feed by sucking blood from a host animal. Fleas do not have wings; instead they have strong jumping legs. Fleas feed on warm-blooded animals, such as dogs, cats, rodents, and people.

What causes flea infestation?

Fleas are parasites that attack a wide range of warm-blooded animals. Fleas develop through metamorphosis. Adult female fleas lay eggs on the dog or cat. The eggs fall to the floor or ground, where they hatch. Larvae are released; the larvae feed on organic material and then develop into pupae. The pupae can remain dormant for long periods. When conditions are good, the pupae hatch into adult fleas. The adult fleas then must find a host for a blood meal, and the life cycle continues. An adult female flea can lay thousands of eggs. Conditions of heat and humidity affect the development of the flea as it goes through its life cycle.

At one time, scientists felt that fleas moved from one animal to another. Now they know that some fleas (such as rodent fleas) do move from one animal to another; however, the cat flea generally stays on its host dog or cat. The cat flea (Ctenocephalides felis) is the most common flea affecting dogs and cats. Fleas cause two conditions in dogs and cats. Flea infestation is the presence of fleas on the animal; the animal may or may not be allergic to the fleas. Fleabite hypersensitivity (FBH) is an allergic reaction to fleas. The animal is allergic to proteins in the flea's saliva; therefore, the flea must bite the animal to cause the allergic reaction.

What are signs of flea infestation or fleabite hypersensitivity?

Flea infestation generally is characterized by the presence of a large number of fleas and flea dirt. Animals with fleabite hypersensitivity (FBH) scratch or bite at their skin. Problems are seen on the skin over the hindquarters and tail area. Scratching of the head or neck is common in cats. Frequently the animal has hair loss (alopecia). The skin is red and irritated. Cats frequently develop "miliary dermatitis" where tiny crusts or lumps develop on the skin in reaction to the fleabite hypersensitivity. Animals with fleabite hypersensitivity may only have one or two fleas causing them to be intensely itchy. It is not uncommon for an animal with fleabite hypersensitivity to have little evidence of flea exposure.

How are flea infestation or fleabite hypersensitivity diagnosed?

Flea infestation is diagnosed by the observation of fleas or flea dirt on the animal. Fleabite hypersensitivity is diagnosed by history and physical examination. Generally, the animal has a typical pattern of skin lesions. Fleas or flea dirt need not be present. Allergy testing can test animals for fleabite hypersensitivity. Two types of allergy testing are available; they include skin (intradermal) testing and blood tests.

How are flea problems treated?

Flea problems are treated by controlling the fleas on the animal and in the animal's environment. Animals with fleabite hypersensitivity will require medical treatment to control the signs of the allergic reaction. These animals are treated with anti-inflammatory medications (such as steroids) and antihistamines.

Control of fleas on the animal:

Control of fleas in the environment:

CAUTION: Pet guardians should be fully informed about the use of any flea control product before using it. Some products require the pet be free of heartworm infection. Certain breeds may be sensitive to some products. In general, cats are more sensitive to flea products than dogs. The pet guardian should check the label to ensure that the product is safe for cats. If the label does not indicate a product is safe for use on cats, the product should not be used on cats. If the pet guardians have any questions, they should discuss the use of the flea control products with the veterinarian. It is important that the pet guardian:

What is the prognosis for animals with flea infestation or fleabite hypersensitivity?

The prognosis (outcome) for animals with flea infestation or fleabite hypersensitivity varies. In warm climates that favor flea propagation, cure is probably impossible. However, the veterinarian can develop effective control plans. Newer flea control products have improved the ability to control fleas. Control is important from a human health aspect as fleas can bite people. Fleabite hypersensitivity can be controlled by preventing flea exposure and by using medications to relieve the pet's itchiness.

The information on this page was obtained from the site www.vetmedcenter.com