|Urban Knowledge Master|
Ctenocephalides felis (Bouche)
Julian R. Yates III
Extension Urban Entomologist
College of Tropical Agriculture and Human Resources
University of Hawaii at Manoa
Cat, dog, opossum, fox, mongoose, rats, chickens, raccoons
The typical reaction to flea bites in humans is the formation of a small, hard, red, slightly raised, itching spot. Bleeding may occur. The single puncture point caused by the flea's mouth is generally apparent in the center of each spot. This characteristic distinguished flea bites from the bites and stings of most other arthropods. Ants and spiders leave two marks when they bite. Mosquitoes, bees, wasps, and bedbugs leave a large swelling or welt.
The irritation is caused by salivary secretions of fleas and varies greatly with the individual attacked. A few people will have a severe reaction, i.e., a general rash or inflammation.
Under optimal conditions, a female flea can lay about 25 eggs a day, 3-18 at a time after each blood meal, for at least 3-4 weeks, and over 800 eggs during her lifetime. Peak production occurs at 6-7 days after emergence. Eggs are laid on the host or where it sleeps. Eggs laid on the host fall off and accumulate in bedding, floor cracks, rugs, furniture, dust and damp soil. Eggs hatch in 2-12 days, are oval, whitish in color, and 0.5 mm in length.
The hairy wormlike white larvae with a distinct brown head (1.5-5 mm long) have 3 stages that may be completed in 8-21 days. In unfavorable conditions, larvae may develop more slowly--taking up to 200 days. Their food is the dried blood copiously defecated by the adults who feed on the host. The "salt and pepper" found where the pet has been sleeping is a mixture of flea eggs (white) and dried blood (black). The larvae spin a cocoon and transform into pupae which can become camouflaged with debris from the environment. Larvae fail to develop at temperatures below 55ûF (13ûC) and at/above 95ûF (35ûC). They die at relative humidities below 45% and above 95%, and hence, are rarely found outdoors in arid climates. Flea larvae move about using setal rings and abdominal hooks.
They are typically found where the animal sleeps or frequents. The pupal stage in favorable conditions lasts 7-14 days, but in adverse situations may be extended to nearly a year. This latter condition may occur in the absence of a host. Emergence takes place in response to detection of host warmth, vibrations, and carbon dioxide emitted from the host during respiration. Massive populations can result from accumulations of generations and their simultaneous emergence triggered by host presence.
Once emerged, the male and female fleas immediately seek a blood meal. These adults are quite small and black in color, but after feeding they expand and appear lighter brown. Adults can live 1-2 months without a meal and can survive 7-8 months with one. Adult fleas jump onto hosts usually from the floor or furniture. Once on a host they can "hitch-hike" considerable distances.
They have about a 15 cm vertical jump.
1) Establish one sleeping area for your pet that can be cleaned easily and regularly.
2) Don't allow pets into areas where fleas may be particularly annoying or where cleaning is difficult.
3) Vacuum areas frequented by pets on a regular weekly basis during the year, more frequently in the late summer and fall when flea populations increase. Dispose of collected material by burning or sealing in a plastic bag and placing in a sunny locations to "cook".
4) Regularly wash all bedding, rugs, etc., to which pet has frequent access.
5) Use a flea comb regularly.
6) Monitor the flea population by keeping records.
7) Bathe the pet if the flea population starts to build up.
8) If a flea collar is considered necessary, place it on the pet as briefly as possible. Between uses, place it in a tightly closed container and store in a cool location.
9) If other poisons are used, follow instructions carefully and protect yourself while applying. Use for the shortest possible time during the most troublesome periods.
10) Consider use of professional services for extremely large populations when the above procedure cannot manage the situation.
Occasional bathing of the animal in soap and water can be used to suppress a flea population, particularly on dogs which are generally more amenable to bathing than are cats. Bathing works by drowning fleas; it is not necessary to use a soap impregnated with an insecticide. However, a soap with insecticidal properties of its own (Safer Agro-Chem) can be used as a shampoo and is registered for this purpose.
The most common flea control method currently in use is the flea collar impregnated with an organophosphate or a methylcarbamate poison. Collars work by emitting pesticide vapors constantly from the neck region of the animal over a 1-3 month period.
The development of the insect growth regulator, methoprene (PrecorR from Zoecon) provides an effective, yet extremely safe material for flea control. This material is applied in a liquid solution or by aerosol to potential flea development areas and arrests the growth of the flea at the pupal stage (7). Methoprene will prevent further development of flea larvae for months after one application, but will not kill adults.
Unfortunately, the temptation may be to overuse methoprene in the manner of the traditional pesticides. Resistance problems have already developed with the insect growth regulators. Powders and dusts are dry formulations of insecticides that are applied directly to an animal or sprinkled in the animal's bedding. Dry formulations are safer than liquid solutions because they contain no solvent to carry the toxicant into the skin. However, powders are breathed in by pets and are also distributed wherever they travel. Care must be taken when using any powder to avoid getting insecticide into the pet's eyes, nostrils or mouth. Aerosol foggers emit gaseous vapors over a large area, and depending upon the active ingredient leave a residue over the entire surface of the living areas long after use. If poisons must be applied over a large area, it is probably best done by professionals who have the proper protective equipment to avoid dermal and respiratory exposures.
Ebeling, W. 1978. Urban entomology. Division of Agricultural Sciences, University of California, Berkeley.
Mallis, Arnold. 1990. Fleas. Handbook of Pest Control, Sixth Edition: 603-615.
National Pest Control Association Technical Release, "Fleas", 7/13/88.
Smith, Eric H. and Richard C. Whitman. 1992. NPCA Field Guide to Structural Pests. NPCA.