Flea allergy in dogs

Flea bite hypersensitivity is a common cause of a severely itchy skin disease in cats and dogs. The itch is caused by an allergic reaction to the flea's saliva which the flea injects into the skin as it feeds. Cats and dogs without this allergic response can tolerate the flea bites, so that they can have fleas and only be mildly itchy. Indeed, there are many cats and dogs without flea allergy that have fleas and show no signs at all. However, in cats and dogs with flea bite hypersensitivity, their skins' reaction to one flea bite is immediate and excessive and this leads to a severe itch for up to one week.

What are the signs of flea bite allergies?

Fleas drive hypersensitive cats and dogs and their skin crazy! It is this hypersensitivity that causes visible signs. Dogs have pink skin, scabby crusts and are biting and scratching at their coat. Hotspots (fast developing dermatitis) can also occur. Cats can develop numerous small crusty lumps, open sores or just hair loss.

Some flea statistics!

The flea is happy to make its home on either cats or dogs; indeed it will even feed on us. Most pets will catch their fleas from another infested pet or place other pets visit. Female fleas lay 40-50 eggs per day. These fall out of the coat and a heavy build up of eggs occur where cats and dogs spend more time, such as sleeping places. The eggs hatch to larvae (or small worms) which prefer living in carpets, bedding and sandy soils, but cracks between wooden floorboards and brick paving will also serve as great flea nurseries. After 5-10 days, the larvae will develop a cocoon and become an adult flea. The adults will remain in the cocoon and hatch when stimulated by warmth, pressure or vibration (like a host walking by). Once on a cat or dog they feed immediately and remain on the host, feeding and breeding. The females can lay 2000 eggs in their lifetime and the lifecycle can be as short as 12 days. This gives fleas an amazing ability to build to large numbers in an extremely short period of time.

How can fleas be controlled?

The best way to control the allergic reaction in an affected cat or dog is to remove the cause, that is remove ALL the fleas. We direct our efforts at:

  1. The patient
  2. Sources of exposure to fleas and
  3. The pets living areas

For the patient and other pets, we use topical applications once every 2-4 weeks. Ideally it is important to treat all in contact animals (at least within the household). If your dog plays with a large group of other dogs in a situation such as a park, it may be both necessary and beneficial to use topical sprays or systemic tablets in addition to topical spot-on applications.

To control those fleas in the home regularly, thorough vacumming should be performed (including under couches/ tables/ bedding). Once weekly washing of the pets bedding followed by hanging it outside in full sunlight to dry is also recommended. This means your pet may need 2 sets of bedding. In addition you can use a "flea bomb" preparation, but please follow directions closely.

Other common breeding grounds for fleas are "sand beds" and patio areas. These can be treated with outdoor products such as Coopex™ (please follow instructions on packaging).