Stress the importance of a vet check if secondary infection is suspected. Therefore, I cannot pass on any helpful information other than to remind you that any and all irregularities on a pet's skin and coat should be reported to the owner. Whether or not he seeks medical attention is left to his discretion, but I would not hesitate, in some cases, to refuse service if a serious problem is not attended to. Well, sometimes it seems that way. New flea control products are being introduced yearly, yet those darned little bugs are getting harder and harder to control.
Fleas thrive in warm, humid conditions, but can turn up in any climate.
Some animals, particularly cats, can withstand flea infestation with only minimal discomfort while others are driven to scratching and chewing by a single flea bite. Not all pets are allergic to fleas, likewise, not all allergies are due to fleas. The allergic reaction to flea bites is caused by something present in flea saliva, and the pet need not be infested to suffer an allergic reaction. Diagnosis is best left to a vet, yet with time and experience you may come to readily recognize a fleabite allergy. The dog may continue to itch for days after the fleas are removed from its environment, yet its condition will improve with time and the absence of fleas.