Understanding the Flea

Thanks to the flea control products available today, flea management is easier and more effective than ever before. Clients often do not realize the damage and irritation that flea infestations can cause their furry friends, as well as their own household. Understanding the fleas life cycle increases our ability to help our clients control their flea population.

Fleas are insects in the Siphonaptera order, meaning they have a siphon-like mouth and no wings. The life cycle is similar in almost all 2,200 species of fleas. Only a few species are problematic for pets, including the cat flea (Ctenocephalitks felis), Pulex simu/ans (common on opossums and raccoons) and the dog flea (Ctenocephalitks canis}, although the cat flea is the cause of most pet and environmental infestations.

Life Goes On

Adult fleas are ectoparasites that live outside their host; larvae live in the host's environment. Fleas are metamorphic, which means they undergo a marked change of form and structure as they grow from embryo to adulthood. Similar to butterflies, their development evolves from eggs to larvae to pupae to adulthood (in simpler terms, egg, caterpillar, cocoon, adult). Depending on their environment, it can take as few as 12 to as many as 350 days for cat fleas to go through growth stages and emerge from the cocoons. At any given time, the flea population typically is made up of 50% eggs, 30% larvae, 15% pupae, and only 5% biting adults.

Optimum temperatures for fleas range from 700P to 85°F, and optimum humidity is 70% to 80%. No flea at any life stage can survive several days in temperatures below 37°F. Most fleas spend winter as either adults on infested animals or as pupae in cocoons in areas protected from freezing. Flea populations typically increase about 5 or 6 weeks after warm spring weather begins and often escalate during the full in midwestern and northern states.

The female flea mates after feeding and begins producing eggs within 1 to 2 days after taking her first blood meal. Then she deposits half-centimeter-long white ovoid eggs (they resemble grains of salt) in a host animal's hair, and the eggs drop off onto bedding, carpet, or soil A single female flea can lay up to 50 eggs in a day and about 2,000 eggs in her lifetime.

After 1 to 6 days, the eggs hatch into larvae that look like small white bristle worms with mouths that can chew: They are blind, long, and segmented and have white hairs. Larvae dislike sunlight and hide in dark places indoors and out, such as grass, soil, carpeting, sand, and gravel. Larvae ingest adult flea feces that contains dried blood, and they molt (or shed) twice within 9 to 200 days. They desiccate (dry up) easily; and relative humidity less than 50% is fatal. Although the typical larval stage lasts 5 to 11 days, it can last up to 2 to 3 weeks if the humidity, temperature, and food availability are just right.

The larvae's third molt produces a whitish~ gray silken cocoon in which pupae develop within a week or two. Since larvae spin cocoons at the base of a carpet, under bedding or at the base of grass, they are protected from insecticides. Outdoors, larvae prefer shaded, cool, moist areas. Full-grown adults in the cocoon detect heat, vibrations, and exhaled carbon dioxide, indicating that a host is near. They can remain in the cocoon for weeks or months while waiting for a host. The adults then leave their cocoons, hop onto that nearby host, find a mate, and repeat the life cycle.

The adult female flea indulges in numerous meals daily; often feeding for up to 3 to 4 hours at a time; she can consume 13.6 mg of blood daily. Soon she begins laying. approximately 150 to 300 eggs per week. She eats significantly more food than she needs, processing most of it into nutritious fecal pellets for her offspring. As you can imagine, a flea infestation can easily lead to an anemia condition in the host animal.

Free at Last

The newly freed adult flea will leap at any likely warm-blooded host/Cat fleas prefer dogs and cats as hosts, but human ankles, ferrets or domesticated rabbits will certainly do in a pinch. Estimates indicate that for every adult flea found on a pet, about 100 fleas are developing in the pet's environment.

Adult fleas come out from the cocoon full size and seek a new host from which they can live for months. Newly emerged adult fleas can survive only about a week without a blood meal. Unlike most houseguests, adult fleas will not leave of their own free will and must be dislodged from their hosts. Grooming activities such as brushing and using a flea comb will dislodge the parasites.

Since many variables affect the fleas life span, the entire life cycle can last anywhere from 2 weeks to 6 months. In the typical home, however, fleas generally live for 3 to 4 weeks. Helping understand that both your pets and your home environment must be treated simultaneously will help them to successfully control flea populations at all stages of their life cycle.

Fascinating Flea Facts

• The average flea is 2 to 3 mm long and weighs one-millionth of a pound.
• Just four female cat fleas feeding four times a day for 100 days will bite a cat or dog 1,600 times.
• Flea "dirt" is actually an adult fleas feces, which is rich in blood and serves as nutritious fecal pellets for her offspring.
• Historians believe that the original job of "lapdogs" was to lure fleas off their owners and onto them!
• Flea brides and grooms (dressed, but dead) were popular collector's items in the 1920s.

For People:
Medication - Relief from itching can be obtained by applying carbolated Vaseline, menthol, camphor, calamine lotion or ice. Highly sensitive persons should consult their physician for advice.
Repellents - Apply on the outer clothing and to exposed skin. Do not use under clothing. N,N-Diethylmeta-toluamide (DEET) is very effective, but should not be used carelessly as severe allergies can develop. Do not apply repellents over cuts, wounds, and irritated skin, around eyes or mouth or to the hands of young children.

Control Measures
Flea control is best achieved with a simultaneous, coordinated effort involving strict sanitation, pet treatment and premise treatment (both indoors & outdoors).
Inspection - Before treatment, discuss the pet's habits with family members to determine where resting and sleeping occurs most frequently. Flea activity "hot spots" can be detected by placing white socks over shoes and walking through the residence into suspected areas. Research has demonstrated that these areas will contain the highest amount of eggs, larvae and pupae even after vacuuming. Hot spots for homes with dogs are usually areas where the pet goes in and out of the house, eats, sleeps and spends time with the family at the base of furniture. For cats, check the tops of refrigerators, cabinets, bookcases and higher locations.
One can monitor flea populations by placing a shallow pan of water with a little dish detergent (acts as a wetting agent which breaks water surface tension) on the floor. Position a gooseneck lamp with the light on about five to six inches above the liquid surface. Adult fleas will leap toward the light at night, fall into the detergent solution and drown. The Happy Jack and pulvex (Zema) flea trap is a commercial apparatus based on the same principle. Also, an ultra light flea trap with a green light attracts fleas into a sticky tray.
Sanitation - Before vacuuming, collect all items (toys, shoes, clothes, etc.) off the floor, under beds, furniture, in closets, etc., to ensure best access for treatment. Also cover fish tanks, remove birdcages, pet food and water dishes and wash or dry clean any pet bedding. Vacuuming carpet with a beater-bar type vacuum where the pet rests and sleeps will help control flea larvae by removing eggs and dried blood feces (larval food) plus opening up the carpet's nap for more effective insecticide treatment. Vacuuming must be performed on a regular basis every other day to be effective. Flea larvae do not move far from the site of hatching when there is adequate food (dried blood feces from adults). Research indicates larvae spend 83 percent of the time deep in the carpet at the base of fibers frequently becoming entwined within the carpet. At pupation, the larva move up the carpet fiber spinning a camouflaging cocoon around itself. Vacuum especially where lint and pet hairs accumulate along baseboards, around carpet edges, on ventilators, around heat registers, in floor cracks, and under and in furniture where the pet sleeps.

After vacuuming, place the vacuum bag in a large plastic garbage bag and discard in an outdoor trash container. If the cleaner uses a liquid water medium in a plastic pan (rather than a dust bag) discard dirty water far away from the house.

Biological - Use an insect growth regulator (IGR), which is a hormone to prevent eggs from hatching and larvae from pupating into biting adults. The IGRs methoprene (Precor) and pyriproxyfen (Nylor, Archer) are odorless and non-staining on carpets or fabrics. Methoprene usually will reduce flea populations up to 95 percent in just 14 days while pyriproxyfen, due to its photostability, lasts in carpets for many months control1ing fleas. IGRs do not kill pupa or adults and are more effective when mixed with an adulticide. Ohio Pest Control operators report few homeowner callbacks when using a water based spray mixture of methoprene (Precor) and propetamphos (Safrotin). Recent research shows the new IGR pyriproxyfen mixed with permethrin will often give 90-day control. IGRs are considered biodegradable and are not known to accumulate in the food chain. Methoprene, approved by the World Health Organization (WHO), is used in drinking water in some countries for mosquito larva control. lGRs are of negligible hazard to humans, pets, and the environment.
Parasitic nematodes, Steinernema carpocapsae (Biosafe, Exhibit, Vector TL) are labeled against flea larvae and pupae in the yard and garden habitats.

Botanicals - Pyrethrins, derived from the flowers of chrysanthemum, and rotenone from the roots of derris, cube and cracca plants, are good contact insecticides. Linalool (Demize), a citrus peel extract, is a natural, fast-acting flea killer, giving short residual control. Other botanicals include d-Limonene (Flea Stop), citronella oil, eucalyptus oil, pennyroyal oil, balsam, lavender oil, calendula, comfrey, rosemary, tea tree oil and yucca.
Feeding pets garlic, brewer's yeast or B vitamins has not been shown to be effective against fleas. Also, pennyroyal, eucalyptus, rosemary, tealeaves and citronella have not provided effective control. In fact, overdosing of garlic or onion can be irritating or toxic to pets.

Prevention - Trim lawns and weeds to create a drier, less-ideal environment for flea larvae. Avoid piles of sand and gravel around the home for long periods of time. Fence yards to prevent dogs from roaming freely in heavily infested areas or contacting other infested animals. Discourage nesting or roosting of rodents and birds on or near the premises. Screen or seal vents, chimneys, crevices, etc. where rats, mice, squirrels, raccoons, chipmunks, etc. may use to enter crawlspaces and buildings. Wash or destroy pet bedding, regularly groom pets and vacuum frequently to remove up to 95 percent of the flea eggs, some larvae and adults. Only about 20 percent of the larvae might be removed when vacuuming since they wrap themselves around the bottom strands of carpeting.

Mechanical Control
An ultra flea comb, a product of Four Paws Product, Ltd. available through your licensed veterinarian, works well to remove fleas from the pet's hair coat

Chemical Control
There are literally hundreds of products on the market for flea control on pets and the premises. For successful flea control, infested pets and the premises need to be treated at the same time.
Before application, read and follow the insecticide label and safety precautions. People and pets should be out of the house when treatments are made, and not return until the treated spray surfaces have dried. Depending on the carpet and the type of treatment, it may take several hours (usually 3-4 hours to give the insecticide a better chance to work). To assist in drying, open windows and use a fan or air conditioner.

Pets - There are many formulations as shampoos, aerosols, dips, sprays, dusts (powders), collars, dabons, spot-ons and monthly tablet or oral liquid treatments. Usually, the most effective pet treatments are available through licensed veterinarians.

Program: recommended for dogs and cats six weeks of age and older. Oral monthly flea medication given with a meal, breaks the flea's life cycle down by preventing eggs and larvae from developing. There is no effect on the adult flea.
Frontline Plus: recommended for dogs and cats eight weeks of age and older. Kills the adult fleas, flea eggs and ticks. It works like no other flea treatment, even in the wet. It moves quickly through the oils on your pet's skin and collects naturally in the hair follicles and oil producing glands. From this reservoir, it is constantly reapplied to the hair and skin, giving you long-lasting flea control. Capstar: recommended for dogs and cats four weeks of age and older and 2 pounds or greater. Capstar begins working within 30 minutes and kills the adult fleas on the pet. It does not prevent fleas from returning. Capstar is safe to use in conjunction with another type of flea control.
Revolution: recommended for use in dogs six weeks of age and older and in cats eight weeks of age and older for the following parasite indications: DOGS - kills adults fleas and prevents flea eggs from hatching for one month and is indicated for the prevention and control of flea infestations, prevention of heartworm disease, and the treatment and control of ear mite infestations. Is also indicated for the treatment and control of sarcoptic mange and the control of tick infestations. CATS - kills adult fleas and prevents flea eggs from hatching for one month and is indicated for the prevention and control of flea infestations, prevention of heartworm disease, and the treatment of ear mite infestations. Is also indicated for the treatment and control of roundworm and intestinal hookworm infections in cats.

Pyriproxyfen (Nylor, Archer), a non-pesticide, is a product of Virbac that is a new 3rd generation Insect Growth Regulator (IGR) - Juvenile hormone mimic. Pyriproxyfen ( a non-pesticide) + permethrin (a pesticide)(Knockout) kills adult fleas and ticks plus kills flea eggs for dogs. Also Knockout* is formulated as a room and area fogger, killing adult and preadult fleas for seven months plus ticks, cockroaches and spiders.

If the homeowner treats the pet, powders or dusts are preferred over sprays. Put on rubber gloves and apply the dust thoroughly into the hair coat according to label directions. Cats are more susceptible than dogs to toxic effects of many insecticides since they groom themselves. Flea collars cannot always be relied upon to bring existing infestations under control. Collars do not kill existing premise infestations. Some animals are sensitive to collars. Watch for signs of dermatitis on the neck under the collar. Some labeled pet collar insecticides include pyrethrins, resmethrin, carbaryl (Sevin), diazinon, naled, tetrachlorvinphos (Rabon) + methoprene (Precor), d-limonene + linalool, rotenone, propoxur, and allethrin. Amitraz collars labeled for dogs only are effective on ticks. After 24 hours, 95 percent of attached ticks become detached.

Indoors - Automatic aerosol foggers, available in a canister, will give good knockdown and kill many biting adult fleas. Insecticides include methoprene + permethrin, pyriproxyfen + permethrin, resmethrin, allethrin, pyrethrins, tetramethrin, rotenone and propoxur (Baygon).
A coarse spray (40 psi) of diazinon (Knox Out 2 FM), propoxur (Baygon) and resmethrin (Vectrin) applied to cracks and crevices of floors, moldings and baseboards up to a height of one foot usually gives good results. Other flea killers include tetramethrin (Bio Flea Halt), amorphus silica gel (Drione, Tri-Die), bendiocarb (Ficam), diatomaceous earth (Answer, Organic Plus), esfenvalerate (Conquer), linalool (Demize) and d-limonene (Flea-Stop).

Since there is no flea resistance to borates, many homeowners try switching to boric acid and disodium octaborate tetrahydrate. Boric Acid (Fleabuster, Flea Halt) is a stomach poison killing fleas in the larva stage. Apply directly on vacuumed, cleaned carpets where pets frequently travel or sleep. Work powder deeply into fibers with a broom or rug rake. For upholstery, remove loose cushions, apply along creases and into comer, not to exposed fabric. Any powder visible after application must be brushed in cracks or removed. Borates are environmentally safe, odorless and used in homes with children and pets.