Flea Handout PDF

Common Myths

Myth 1: My cat can’t have fleas because she never goes outside.

Fact 1: People and other pets (such as a dogs) can bring “hitch-hiker” fleas into your home, where they can infest your indoor pet!

Myth 2: We can’t have a flea infestation because we only have hardwood floors.

Fact 2: Developing fleas can thrive in the cracks between the boards of hardwood floors, along baseboards, and under furniture.

Myth 3: My pet can’t have fleas – he’s not itchy!

Fact 3: Pets become itchy during a flea infestation because they are allergic to flea saliva (known as Flea Allergy Dermatitis, or FAD). Pets can have varying degrees of sensitivity to flea saliva, just like people can have varying degrees of allergy to pollen or nuts. Some dogs can have profound flea infestations and not be itchy at all, while other dogs may be very itchy with only 1 or 2 flea bites.

Myth 4: My pet can’t have fleas because I would see them.

Fact 4: Many animals, especially cats, are fastidious groomers and will lick away adult fleas. Sometimes the only sign of fleas may be the presence of characteristic skin diseases caused by Flea Allergy Dermatitis (FAD).

Myth 5: My pet can’t have fleas because I’m already treating her for fleas!

Fact 5: Many over-the-counter flea treatment products (shampoos, flea collars, generic topical treatments, etc.) are not as effective as prescription flea treatments available through your vet clinic.

The Flea Life Cycle

The Egg
At least half of the flea population in an infested home is in the egg stage. An adult female flea lays 40-50 eggs per day. These eggs are laid on the host and fall off into the environment to incubate. Flea eggs prefer to incubate in a high humidity environment at 65-80˚ F (just like your house!)

The Larva
Larvae look like little maggots and are approximately 0.5cm long. They feed on the blood found in adult flea feces, flea eggshells, and other flea larvae. Flea larvae like to develop in cool shady areas outdoors, as well as in protected indoor areas such as carpeting, along baseboards, and under furniture. The time spent as a larva depends on environmental conditions, but it can be a short as 9 days.

The Pupa
Pupae look like tiny white specks. They can be found in carpets, under furniture, and on animal bedding. The can also be found outdoors in the soil and on plants. The pupa can remain dormant for many months to over a year as it waits for the opportune moment to emerge. The mature pupa can detect the presence of a host based on vibrations, carbon dioxide gradients, heat, and sound patterns. When a mature pupa feels the time is right, it emerges from the cocoon ready to attack its host.

The Adult
Once the adult flea finds a host and takes its first blood meal, they set up shop permanently. Adult fleas rarely leave their host (contrary to the popular belief that fleas “jump” from host-to-host). A female flea begins producing eggs within 20-24hrs of its first blood meal. At a rate of 40-50 eggs per day, a female flea can produce up to 2,500 eggs in her 4-8 week lifespan!

On average, the time period from egg to adult is about 3 weeks.

Getting Rid of Fleas

Don’t panic! Eradicating fleas from your pet and your home will take time, but it can be done. The most efficient way to eliminate a flea infestation is to treat your pet AND the environment.

Treating The Environment


  • Vacuum several times a week to remove flea eggs/larvae/pupae from your home. Tape the vacuum bag shut and discard it every time you vacuum.
  • Wash and dry all bedding, stuffed toys, etc. Flea larvae are killed at 95˚ F, so wash with hot water if possible and run everything through the dryer.
  • Treat all upholstery, cushions, pillows, drapes, etc. that cannot be easily washed with a commercial indoor flea spray. When using these products, be sure to apply the product lightly and uniformly on all surfaces without saturating them. Make sure you spray underneath and behind all furniture, remove couch cushions and spray underneath them, etc. Start spraying at one end of the room and work backward towards the exit. Do not re-enter treated areas until they are completely dry. **Please note that area sprays such as Knock Out® are more effective than foggers because they can be sprayed under furniture and in other areas that foggers can’t reach.**
  • If you do not wish to treat your home yourself you can contact an exterminator for the service.


  • If your pet spends time outdoors in a kennel or doghouse, wash or discard the bedding. You should spray these areas with the same indoor flea spray that you used indoors.
  • If you have a recurrent flea problem you may need to treat your lawn as well. Use a professional grade yard treatment. These products are available in a variety of types including granules, powders, and sprays. They can be purchased at most pet stores and hardware stores. It is especially important to treat moist and shaded areas where flea pupae/larvae like to hang out.

Treating Your Pet

  • All dogs and cats in your home must be treated at the same time! If one pet is left un-treated they can serve as a reservoir for fleas.
  • Use a prescription-strength flea & tick preventative according to the label. Effective products are available in topical (applied to the skin), oral (chewable), and collar forms. Your budget, household, and pet’s lifestyle will all be taken into consideration when we make a product recommendation for your pet.
  • Most commercial flea treatments have flea-specific neurotoxins as their active ingredient. These treatments are very safe for you and your pet because they act on neurotransmitters that mammals do not have. These neurotoxins hang out in or on your pet’s skin. Fleas are exposed to the toxin when they contact your pet’s skin or bite them. As the toxin begins to work, the flea becomes disoriented and is eventually paralyzed, at which point it falls off the host and dies of starvation. Because of this, you may see MORE fleas on your pet after using a flea treatment because they become less adept at hiding once the toxin begins to work.

Eliminating a flea infestation usually takes around 3 months of diligent work. The process of cleaning and spraying the environment should be repeated 6 weeks after the first treatment. After two environmental treatments 6 weeks apart there should not be any further need to treat your home as long as you continue to use a prescription flea preventative on your pet.

The best way to prevent a flea infestation is to keep your pets on a prescription flea preventative year round.

Signs of a Flea Infestation

  • Flea feces (pepper-like specks) and flea eggs (light-colored specks) on bedding and in your pet’s coat
  • Itching, biting, and scratching
  • Hair loss, especially around the base of the tail and neck
  • Bumpy/scabby skin (especially seen in cats)
  • Small brown insects scurrying around on your pet


  1. Wendy C. Brooks, DVM, DipABVP, Educational Director, VeterinaryPartner.com
  2. Grace SF. Fleas. In: Norsworthy GD, Crystal MA, Grace SF, et al, eds. (2006). The Feline Patient. 3rd ed. Ames, IA: Blackwell Publishing; 106-107.
  3. https://www.petbasics.com/dog-education/flea-life-cycle/
  4. “Life Cycle: Fleas”, Handout, Companion Animal Parasite Council
  5. “Flea Allergies in Pets”, Clermont Animal Hospital, www.clermontanimal.net, 2008

Updated January 2017