Fleas are small, brown or black wingless insects with flattened bodies. Several types of fleas infest the hair coats of animals, and some occasionally feed on people. Even if you have a flea problem, you may never see a flea on yourself, because they prefer to jump on your dogs and cats. These blood-sucking insects cause considerable irritation and distress to infested pets. Severe infestations may lead to anemia from blood loss. A fleas bite can also cause your pet allergic symptoms such as: itchiness, rashes and sores that can become secondarily infected. Pets can be infested with the common tapeworm by grooming out the fleas and ingesting them.

The best places to look for fleas on your pet are the hind quarters, base of the tail, stomach and groin regions. Sometimes no fleas are found, only tiny, black granules that resemble pepper. This material is flea feces commonly called flea dirt and consists of digested blood. To distinguish this material from dirt, smudge it on white paper or add a drop of water to it. If you see a reddish-brown color, you pet has fleas, even if you cannot find them.

Life Cycle

Toxocara canis LifeCycle roundworm:
(click to enlarge)Fleas must first take a blood meal to reproduce eggs. These eggs fall off of your pet throughout the life of the flea and concentrate in areas where your pet spends the most time. A single breeding pair of fleas may produce 20,000 fleas in 3 months. Eggs hatch after 2 – 12 days into larvae that feed away from your dog in the environment. Larvae molt 2 times within 2 – 200 days and the older larvae spin a cocoon in which they remain for 1 week to 1 year. The long period during which the larvae remain in the cocoon explains why fleas are difficult to eradicate from the environment. Many insecticides only kill the adult flea and have a short residual life. Depending upon environmental conditions the flea life cycle can be completed in as little as 11 days or it may take as long as a year and a half.

Flea Control

Fleas are amazingly hardy. They can survive virtually anywhere for up to two years without feeding. Ten females can produce 250,000 offspring in just one month. Effectively treating your dog and cat for fleas in the past has been a very difficult task. This was mainly due to the insecticide being focused on killing of the adult fleas, doing nothing to halt the life cycle or address the large number of eggs produced. Recently, a new generation of flea control medications are available through veterinarians. These products focus on the flea’s life cycle, making total control of an infestation possible.