Flea
Flea
Insect, the basic features of adults
Insect, the basic features of adults
Flea bite - close-up
Flea bite - close-up

Fleas

Definition:
Fleas are wingless, blood-sucking insects that feeds on dog, cats, humans and other species.

Alternative Names:
Dog fleas; Siphonaptera

Causes, incidence, and risk factors:
Fleas prefer dog and cat hosts, but in the absence of a preferred host will use humans or other available animals as a host. Pet owners may not be bothered by fleas until their pet is away for an extended period of time and the fleas, in the absence of their normal host, begin to bite the owners. Bites frequently occur around the waist, ankles, armpits, and in the bend of the elbows and knees.
Symptoms:
  • Rash, papular
  • Papule may have small hemorrhagic area
  • Papulesitch
  • A localized rash
    • Skin rash or lesion located on the armpit or fold of a joint (at the elbow, knee, or ankle)
    • The amount of skin area affected increases over time (enlarging skin rash or lesion) or the rash spreads to other areas
    • When pressed the area turns white (blanches to touch)
  • Severe itching
  • Hives
  • Swelling only around a lesion (sore) or injury
  • Generalized itching (pruritus) or itching of the skin rash
  • Skin folds such as under the breasts or in the groin may be affected (intertrigo)
Note: Symptoms often begin suddenly (within hours).
Signs and tests:
No testing is necessary.
Treatment:
The objective of treatment is to break the flea life cycle by treating the home, the pets, and the outside environment with insecticide. Home foggers and flea collars are not always effective. Birds and fish must be protected during spraying. If home treatments are ineffective, professional extermination may be needed.

Calamine lotion helps relieve itching.
Expectations (prognosis):
Once fleas are established, eliminating them requires persistence. The problem will continue until the fleas are eliminated.
Complications:
Secondary skin infection caused by scratching can develop after flea infestation.
Calling your health care provider:
Apply home treatment and call your health care provider if there are signs of complications.
Prevention:
Prevention may not be possible in all cases. Use of insecticides may be helpful if fleas are common in your area. Professional extermination may be necessary in some cases.

Review Date: 8/14/2001
Reviewed By: Elizabeth Hait, M.D., Department of Pediatrics, Rainbow Babies and Children's Hospital, Case Western Reserve University, Cleveland, OH. Review provided by VeriMed Healthcare Network.
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