This is disease is caused by measles or rubeola virus which is an RNA paramyxovirus. Its characteristic rash is due to hypersensitivity to skin viral antigens. It has pathognomonic Koplik spots close to parotid duct which shows ulcerated mucosal lesions with necrosis and neutrophils. Subacute sclerosing panencephalitis and inclusion body encephalitis which occur in immunocompromised individuals may be late complication. But it is easily preventable by vaccination.