This mite burrows under the skin to lay its eggs. Some dogs can harbor the mites without reaction, but others develop a severe allergy to the presence of these spider cousins. This mange can seriously debilitate an affected animal. Some dogs become allergic to flea bites, making flea control an important part of the family's dog care plan. One flea can cause a reaction in a sensitive dog.
Fleas are also vectors for tapeworms.
Ticks don't hang around long enough or bite frequently enough to cause major skin problems, but they are vectors for Rocky Mountain Spotted Fever and Lyme Disease that they can transfer to dogs through their bites. Ticks are more difficult to kill than fleas and there are no organic or biological controls for these spider and mite kin. The best preventive is to examine the dog after he has been in fields or woods, remove any ticks, and place them in a vial of alcohol. Immune deficiencies Canine autoimmune diseases can cause skin problems ranging from loss of hair or pigment to blindness. The immune system malfunction that allows these diseases to develop may be inherited, although related dogs may have different diseases.