Fleas: Treatment and Prevention

a fleaIf your dog or cat is itching and scratching, fleas are a likely culprit. Flea season usually begins in spring and lasts through the summer into early fall, but fleas can survive year round in western Oregon’s moderate climate.

Flea bites can cause local skin irritation and swelling that may cause your pet discomfort.

Some dogs and cats develop an allergic reaction to flea bites, resulting in adult fleas bitingscratching, which can lead to hair loss or to a bacterial skin infection known as”hot spots.” Fleas can host tapeworms, and can transmit bacteria, viruses, and protozoa.

Fleas that live on your pet can also infest opossums and raccoons, which can be important sources of flea infestation hot spots outdoors. Therefore, it’s important to treat both your pet and your pet’s environment. A flea control program is most effective when you treat your pet, your living areas, and your yard at the same time.

Flea Life Cycle

Depending on the climate and the availability of a host, the length of a flea’s life cycle is variable. The female flea can lay up to 2000 eggs in her lifetime. The eggs fall off of the animal, which acts like a “living salt shaker” of flea eggs. Between 1 and 10 days later, the eggs will hatch into larvae in the environment. Larvae live anywhere from 5 to 11 days before they become pupae.

Pupae are difficult to eliminate, as you must wait for them to develop into adults before treatment will be effective. This stage is resistant to extreme environmental conditions, as well as chemical interventions that may be applied to the environment. It may take anywhere from 7 days to 14 days for pupae to develop into an adult flea; however, their emergence is largely dependent on heat, humidity, physical stimulation, and carbon dioxide from exhaled breath. Depending on these external factors, the pupae may “hatch” from their cocoon in 14 – 180 days and maybe even longer!

Once they emerge, an adult flea may live on a host up to 120 days. Fleas rarely jump from host to host. During peak flea season, the life cycle is about 3 weeks. At any given time, less than 5% of the flea population is adults, so it’s important to treat your pet, home and yard for all stages of the flea life cycle.

Signs of Flea Infestation

"flea dirt"

“flea dirt”

  • Adult fleas on your pet’s skin or in your house.
  • Flea excrement (dark specks that turn reddish in water), also called “flea dirt,” on your pet’s skin.
  • Irritated skin or excessive itching, which can lead to hair loss or a bacterial skin infection known as “hot spots.”
  • Flea eggs (white oval shapes the size of table salt crystals) hung up in your pet’s coat .

Treating Your Pet for Fleas

There are several treatment options, and your Vet can help you determine which is the most appropriate for your family. They include:

  • Adulticide
    An adulticide, such as a topical monthly-use product, is applied directly to the pet’s skin, where it is toxic to adult fleas, providing quick relief. Some oral tablets can be administered up to once a day or once a month.
  • Insect Growth Regulator (IGR)
    An Insect Growth Regulator (IGR) is found in combination with some topical adulticides. IGRs do not kill fleas but do kill eggs and larvae to break the flea life cycle.
  • Insect Development Inhibitor (IDI)
    An Insect Development Inhibitor (IDI) can be administered orally on a monthly basis or every 6 months by injection. An IDI keeps flea larvae from maturing to the next life stage, which also breaks the life cycle.
  • Integrated Flea Control
    If you are experiencing an infestation, your veterinarian may suggest using both an adulticide and either an IGR or an IDI. This is called Integrated Flea Control and serves to rid your home of an infestation more rapidly.
  • Flea shampoo, dip, spray, combing, collar
    These can be effective temporarily, but generally do not yield lasting results.

Treating Your Pet’s Environment

Treating your house, garage, yard and kennel is another important step in controlling fleas.

  • For best results, treat your living areas and yard on the same day that you treat your pet.
  • “Critter-proof” your yard by identifying sites in the yard that pets or wildlife may use as shelter. These include crawl spaces, areas under deck, porches, stairs, shrubs, or trees. Prevent access to any of these areas if possible. This is much more effective long-term, rather than trying to treat the outdoors, as these treatments only address 5% of the flea population or “the tip of the iceberg.”
  • Regular vacuuming and steam cleaning helps remove flea eggs, larvae, and pupae. Don’t forget to dispose of the vacuum bag, as fleas can hatch in the bag after vacuuming.
  • A self-directed spray that will kill flea eggs and larvae in addition to adult fleas is the best choice for treating your house, garage, yard and kennel.
  • If you must treat your yard, a pet-friendly lawn granule application that will kill flea eggs and larvae in addition to adult fleas is best.
  • Foggers aren’t able to treat underneath objects that fleas love to inhabit, such as couches, so it’s best to use a spray to reach under those items.

Courtesy of the Oregon Veterinary Medical Association