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 is a prevalent autoimmune skin disease resulting in the loss of hair on the scalp and elsewhere on the body. It usually starts with one or more small, round, smooth patches on the scalp and can progress to total scalp hair loss (alopecia totalis) or complete body hair loss (alopecia universalis).