Exanthema (rash) - a discrete pathological formation of the skin, its response to the effects of toxins and metabolites of the pathogen. Reaction of the skin is manifested by the fullness of the vessels of the microcirculatory bed, increased vascular permeability with the development of edema and hemorrhage, necrosis of the epidermis and deeper layers of the skin, dystrophic changes in cells (balloon dystrophy), serous, purulent, serous-hemorrhagic inflammation.