Veterinarian - Melbourne
1029 Sarno Road
Melbourne, FL 32935
(321) 254-1754

FLEA-BITE HYPERSENSITIVITY AND FLEA CONTROL BASICS OVERVIEW

  • “Hypersensitivity” is an increased sensitivity or reaction in the skin due to the presence of a foreign substance; in flea-bite hypersensitivity, the foreign substance is found in flea saliva; the reaction is immune based and would be considered to be an “allergic” reaction
  • “Dermatitis” is the medical term for inflammation of the skin
  • “Antigens” are substances that induce sensitivity or immune response
  • “Flea-bite hypersensitivity” or “flea-allergy dermatitis”—hypersensitivity reaction to antigens in flea saliva, with or without evidence of fleas and flea dirt
  • “Flea infestation”—fleas and flea dirt are present on the pet, with or without signs of flea-allergy dermatitis
  • “Flea-bite dermatitis”—inflammation of the skin due to the flea bite itself; it is not an allergic or hypersensitivity reaction, but rather an irritant response to flea bites

GENETICS

  • Flea-bite hypersensitivity—unknown inheritance pattern; more common in breeds with atopy (disease in which the animal is sensitized [or “allergic”] to substances found in the environment [such as pollen] that normally would not cause any health problems)

SIGNALMENT/DESCRIPTION of ANIMAL

Species

  • Dogs and cats

Mean Age and Range

  • Flea-bite hypersensitivity—rare in pets less than 6 months of age; average age range, 3 to 6 years, but may be seen at any age

SIGNS/OBSERVED CHANGES in the ANIMAL

  • Depend somewhat on the severity of the reaction and the degree of exposure to fleas (that is, seasonal or year-round)
  • Itchiness (known as “pruritus”)
  • Compulsive biting
  • Chewing (“corncob nibbling”)
  • Licking, primarily in the back half of the body, but may include other areas
  • Cats—scratching around the head and neck
  • Signs of fleas and flea dirt; finding fleas and flea dirt is beneficial, although not essential, for the diagnosis of flea-bite hypersensitivity; sensitive animals require a low exposure to fleas to have an immune response and they tend to over groom, removing evidence of flea infestation, and making identification of parasites difficult
  • Hair loss (known as “alopecia”)
  • Small, raised skin lesions (known as “papules”)
  • Darkened skin (known as “hyperpigmentation”) in dogs
  • Thickening and hardening of the skin, usually associated with hyperpigmentation (known as “lichenification”) in dogs
  • “Hot spots” in dogs
  • Miliary dermatitis (skin inflammation characterized by numerous, small, crusty bumps) in cats

CAUSES

  • Fleas
  • Immune response to flea saliva (flea-bite hypersensitivity or flea-allergy dermatitis)

RISK FACTORS

  • Flea-bite hypersensitivity—intermittent exposure to fleas increases likelihood of development; commonly seen in conjunction with atopy (disease in which the animal is sensitized [or “allergic”] to substances found in the environment [such as pollen] that normally would not cause any health problems)

TREATMENT HEALTH CARE

  • Outpatient treatment

MEDICATIONS

Medications presented in this section are intended to provide general information about possible treatment.