A desert is a region of land that is very dry because it receives low amounts of precipitation (usually in the form of rain but may be snow, mist or fog), often has little coverage by plants, and in which streams dry up unless they are supplied by water from outside the area.
Alopecia areata is an autoimmune disease. Autoimmune means that the body's immune system attacks the body. When alopecia areata develops, the body attacks its own hair follicles. A person's genetic makeup, combined with other factors, triggers this form of hair loss.
Alopecia areata facts. 1  Alopecia areata is a hair-loss condition which usually affects the scalp. 2  Alopecia areata causes one or more patches of hair loss. 3  Alopecia areata affects both genders. 4  It is an autoimmune disorder, in which the immune system attacks hair follicles, is believed to cause alopecia areata.lopecia areata is occasionally associated with other autoimmune conditions such as thyroid disease, vitiligo, lupus, rheumatoid arthritis, and ulcerative colitis. The diagnosis or treatment of these diseases is unlikely to affect the course of alopecia areata.