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Flea bite hypersensitivity or flea allergic dermatitis is very common in cats. In fact, it is the most common skin disease to be diagnosed in pets. Flea allergies usually develop when cats are young (less than one and up to five years of age), but can begin at any age. Flea saliva is actually believed to be the cause for the allergy or sensitivity.
The flea life cycle includes the adult flea, egg, larva and pupa. Adult fleas do bite, but cannot survive long if they are not on an animal. Once the adult flea lays its eggs on the host cat it will fall off, leaving the eggs to mutate through the rest of their life cycles. The rest of the flea's life cycle then occurs on the host cat, and the generational cycle continues and grows until the flea population has been eradicated entirely.
Flea bite hypersensitivity or flea allergic dermatitis usually causes severe itching, a condition that is medically referred to as pruritis. Since as few as one or two flea bites a week can cause pruritis, symptoms will often persist even after some form of flea control has been applied. Most cats will have symptoms that worsen with age, but symptoms are also often episodic. Cats especially will sometimes suffer from a related conditon called neurodermatoses, a behavioral problem that comes about as the result of anxiety related flea bite hypersensitivity.
Most owners will first notice frequent and severe itching and scratching, hair loss, and scabs on their cat's skin. Many times the hind end is affected more than the front of the body or the head, however, cats that are suffering from an allergy to fleas can have lesions anywhere on the body. Moreover, fleas or flea dirt may or may not be readily visible.
Using a flea comb to inspect your cat, fleas or flea dirt may be seen more easily. Skin tests for mites or bacterial skin diseases may also be recommended if the fleas cannot be seen. Sometimes the best diagnostic method is just to treat for fleas.
Any type of arachnid excluding ticks
An insect that has hatched from an egg but has not yet reached the pupal stage
A condition in which the skin becomes inflamed
Term used to imply that a situation or condition is more severe than usual; also used to refer to a disease having run a short course or come on suddenly.
A reaction to a certain pathogen that is out of the ordinary