Prickly heat rash is a red corn-like papule on the skin, accompanied by strong itching and tingling sensation, common in hot and humid climate, caused by sweat gland duct obstruction or excretion disorder. The reason for the onset of prickly rash-like rash 1, sweat duct obstruction or excretion disorder The formation of prickly heat is due to high summer temperatures, high humidity, excessive body sweating, not easy to evaporate, sweat impregnated epidermal keratin layer, resulting in sweat duct mouth occlusion, sweat ducts within the storage of sweat, due to increased internal pressure and rupture, sweat infiltration into the surrounding tissue caused by stimulation, herpes and papules at the sweat hole, prickly heat occurs. Some doctors also believe that the occlusion of sweat holes is a primary staphylococcal infection of sweat holes, such infection is related to the hot and wet environment. 2, allergic reactions and allergies such as rheumatic fever patients in 1/3 can appear a variety of rashes. The most common is annular erythema and subcutaneous nodules, rash this disease is accompanied by fever, sweating, arthralgia and accelerated blood sedimentation and other reactions. 3. Acute rash infections Acute rash infections include scarlet fever, rubella, chickenpox, measles, dengue typhus, rash scrub typhus, typhoid fever, paratyphoid fever, diphtheria, hare fever, horse nose gangrene and many other diseases. It is characterized by a rash mostly accompanied by different forms of fever.