Identification, Facts, & Control

Latin Name

Order: Siphonaptera


Flea.jpg Small 1/16 to 1/8-inch, brown with a slender body

Fleas and Disease

Bubonic plague, or "Black Death", on at least two occasions in history, has killed off massivepopulations of people. This disease is caused by the bacteria, Yersinia pestis. In the early days, this organism infected mainly the Norway rat, and was carried from rat—to—rat and from rat·to—man by the Oriental rat flea.Nowadays, the disease still exists in California but primarily in wild rodent populations, such as the ground squirrel. The danger is when the rodent dies, and the fleas leave the carcass. In parks and recreation areas in California, residents are warned not to pick up sick or dying ground squirrels, chipmunks and similar animals.The bacterium is in the blood of the animal that is infected with plague. After the flea sucks the rodent’s blood,the organism causes a blockage in the ilea’s intestinal tract. When the “blocked" flea later bites a person, it regurgitates and the infected blood it gets into the bloodstream of the person. For some reason, the Oriental rat flea becomes blocked more readily than other fleas.

Other species of fleas are involved in the transmission of a form of typhus fever. But this problem is much more prevalent in other countries than in the U.S. The more immediate problem for the PCO is the irritation that comes to individuals from merely being bitten by fleas. The reaction varies a great deal from small red bites in some cases to severe rash with itching in others. Close inspection of a flea bite shows a tiny central red spot where the mouthparts pierced the skin; there seldom ever is much swelling.

General Characteristics of Fleas

Small, wingless, brown to black, blood~sucking insects. They belong to the Order "Siphonaptera". "Siphonaptera" means that they have piercing sucking mouthparts that are somewhat like a "siphon"; and that they do not have wings ("a" = without; and "pteron" = wing). Fleas are distinctly flattened laterally, and have spines on the body that are aimed backwards. This enables them to move rapidly and efficiently through the body hair` of an animal. Their maximum jumping ability is 7"—8" vertically and l4"-l6" horizontally. By far the greatest source of flea infestations that the PCO is called upon to control is a pet dog or pet cat.

Life Cycle

Metamorphosis is complete: egg, larvae, pupae, adult. The time required to complete a cycle depends on temperature, humidity, and the food available to the developing insect.

Mating takes place on the host animal. The female must have a blood meal before she can lay fertile eggs. The female mates only once, and lays her light colored eggs loose on the host animal. They immediately fall from the pet’s body onto its bedding, onto the ground, or wherever else inside or outside the building where the pet is located at the time. The flea lays her eggs after each blood meal, but not all at once. They have between 1 to 12 days.

The larvae are worm—like, white, blind, without legs, and have chewing mouthparts. They feed on all types of organic debris as well as flea feces, animal feces, and dried blood. They are rarely seen, but are quite active and can be found in floor cracks, rugs, dog kennels, and in and around the pet’s quarters. The larval stage lasts from a week or two in the summer when the temperature and other conditions are right, to several months at other times.

The pupa is formed by the larva during its last instar. The larva spins a cocoon around itself, and then encrusts itself with various types of debris, including sand if it’s available. This camouflages the cocoon and makes it hard to find. The pupal stage lasts from I to 2 weeks. But sometimes a new adult will remain inside the pupal case awaiting a proper stimulus —· staying in the pupal stage as long as several months. For example, most fleas that infest buildings are very sensitive to vibration. Oftentimes, people returning to their home from vacation are greeted by numerous biting fleas soon. after the floor has been walked on (causing vibration). The fleas then promptly emerge from their cocoons and search for a blood meal. Certain fleas on wild rodents will emerge from their cocoons only when proper humidity conditions occur. This might be only once per year in dry desert areas.

The adult female flea will lay eggs only after she has obtained a blood meal, even though she has been mated.

Sand Fleas

These are small crustaceans commonly found on beaches. They are not insects. Many so called "sand fleas" in California are believe to be merely cat flea or human flea infestations thatare located in or around buildings located near sandy beaches.

The Main Kinds of Fleas Attacking Man
(Cat flea, dog flea, human flea, and oriental rat flea)

Each species of flea usually has its own preferred host. But many will suck a blood meal from a variety of hosts, including man, even when the preferred host is present. For example, the cat flea (Ctenocephalides felis), and the dog flea (C. canis) are the two fleas most commonly associated with man in the U.S. However, they must have access to a dog or cat or other animal for the infestation to be maintained. And the human flea (Pulex irritans) also feeds on ground squirrels, dogs, and other animals in addition to people. This flea is I known for its rapid blood sucking on humans and leaving blood spots. These blood spots are used by flea larvae for food. A fourth important flea is the Oriental rat flea (Xenopsylla cheopis). lt is the principal vector of bubonic plague from rat to man.

Notes on the Control of Fleas
  • An increase in flea bites to people usually means the normal host has been absent for some time.
  • Most flea infestations in buildings will be either cat fleas or dog fleas. Ask the owner details about the animal’s habits, explaining that fleas usually are most abundant around the pet’s resting area. > The owner should wash the pet’s bedding and vacuum the rugs, furniture and baseboards before the pest treatment; and remove, seal I up and immediately dispose of the vacuum cleaner bag.
  • Pets are not always the source of a flea infestation. The source can be wild animals in the crawl space.
  • It is usually necessary to treat both inside and outside premises to achieve control of a flea infestation.
  • A PCO should not treat the host animal for fleas. A veterinarian or the homeowner should do this. And it should be done on the same day the premises are treated.
  • It is a good practice to treat premises for rodent ectoparasites (fleas, mites, sometimes lice) in conjunction with rodent control, in order to prevent problems of the ectoparasites abandoning the dead carcasses and attacking people.
  • Flea larvae are most likely to be found in the undisturbed dust, lint, and debris in carpet and flooring of a residence & when treating one should use a fan spray.
  • Fleas are most active when the weather is hot and dry.
  • Effective control measures in buildings include
    1. recommending sanitation and cleaning to the occupant
    2. using pesticides registered for flea control.
  • If the homeowner has a cat or dog it would be wise to recommend they treat their pet/s for fleas the same time the residence is being treated in order to prevent re-infestation.
  • To maintain treatment effectiveness after spraying the exterior of a residence for fleas it should be recommended to the owner the he/she keep grass mowed, eliminate moisture conditions around pet A areas, and remove debris.
  • Owners should be warned that cat fleas often cause children in a residence to have allergic reactions.
  • If fleas are in the pupa stage pesticides are virtually totally ineffective. Because of this fact, it is important to inform the homeowner to vacuum after the treatment of fleas so that the pupa will turn into an adult.
  • Methoprene is an excellent chemical to use on fleas because it inhibits their pupal formation.
  • The application rate of the pesticide and the square footage to be treated would be the formula by which to prepare the proper amount of 1% insecticide for a flea treatment.
  • The quickest means of knockdown for the control of fleas in a lawn area is to use a power spray. > IGR’s (Insect Growth Regulators - The best is called Hydroprene) are good to use with fleas because they prevent fleas from reproducing. Tank mix with a residual insecticide is an acceptable practice for enhancing the use of IGR’s.
  • Once all the spray residues have dried (unless stated otherwise on the pesticide label) after treatment it is considered safe for pets to return to the residence.
  • It is the responsibility of the company giving treatment to schedule the reentry time after the treatment (before treating the interior of a residence begins).

Click on a species of pest below to learn further information.