Causes and Prevention of Fleas in Dogs

Source: PetWave, Updated on July 16, 2015

Causes of Flea Infestation

Dogs become infested with fleas when they live in an area that is conducive to the flea life cycle, and when appropriate flea preventative steps are not taken. Fleas thrive in warm, damp climates. An average temperature in the range of 70 to 85 degrees Fahrenheit, in a moist environment, is optimal for these parasites. From a flea’s perspective, the hotter and damper, the better. Accordingly, dogs living in hot, humid areas tend to develop more severe complications from flea infestation than do dogs living in cold, dry climates. Dogs can also get fleas by coming into contact with other animals that have a flea problem.

Fleas only spend a small part of their lives on the skin of a host animal. Adult fleas mate after they eat a large blood meal. Females lay their eggs within 1 to 2 days; they can produce upwards of 2000 eggs during their short 4-month lifespan. Flea eggs fall off of the host shortly after they are laid and incubate wherever they land. The eggs hatch into larvae in about 10 days. Flea larvae can survive for a long time in the environment – reportedly up to 200 days. Fleas tend to like deep pile and shag carpeting, floor cracks, furniture and bedding. They eventually spin a cocoon and enter a pupal stage, which can last anywhere from days to months. This is considered to be a resting phase, during which the pupae do not eat. Once the temperature and humidity are right, the pupae hatch from their cocoons and emerge as immature adults. They have one to two weeks to find a host, or else they will die. Adult fleas can live up to 4 months on a dog, but they cannot survive very long in the environment. Only about 1% of the total flea population, at any given time and in any given area, is comprised of adults. Most fleas are free in the environment in egg, larval or pupal forms.

Prevention of Flea Infestation

Fortunately, there are many things that dog owners can do to keep fleas under control. Some of the most effective ways to manage fleas are to keep a dog’s living environment clean and to use veterinarian-recommended flea preventatives. Regular grooming will give owners an opportunity to inspect their dogs’ skin and coat for fleas and other external parasites. If open wounds or suspicious “salt-and-pepper” particles are present, whether or not adult fleas are actually seen, a trip to the veterinarian is probably worthwhile. The salt-like particles are flea eggs; the “pepper” particles are flea feces.

Special Notes

Fleas from dogs can and do bite people, which means that flea infestation has zoonotic potential. Fleas have an unparalleled ability to jump great distances and to great heights. Adults will jump onto a host animal and begin feeding as quickly as they can. A single adult flea typically feeds for at least 8 hours a day, ingesting about 15 microliters of blood during that time. Fleas need to feed on blood before they are able to reproduce.

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