疾病的感染有其臨床路徑，傷寒論三綱學說的內容色含太陽病風中衛、寒傷營、風寒兩傷營衛等三條臨床路徑o 太陽病體表為風寒邪氣入侵的途徑，榮衛乃人體對抗邪氣入侵的防禦系統，與微循環系統密切相關。傷寒論將風寒邪氣所引起的疾病分為三陽病和三陰病。由體表至內臟組織器官的慢性炎症感染疾病，稱為太陽病;太陽病內傳陽明或病邪經由口腔直接進入腸胃道，引起胃家實，統稱為陽明病。病原體由太陽病或陽明病的病住區，經血行感染入侵少陽病的病社區，所引起組織器官的炎症浸潤，稱為少陽病。而三陰病多由太陽病慢性病變引起器官機能衰竭，少陰病色括循環性休克或心臟衰竭，太陰病為肝失代償，厥陰病包括急、慢性腎衰竭綜合徵。

The Infectious diseases ordinal had a clinic pathway, the three principle theoretical content of Shang han lun included three clinic pathway of wind evil damage defense, cold evil damage construction, wind-cold evil damage construction and defense of Greater yang disease. The body surface of Greater yang disease is an invaded entrance of the wind or cold evil. The defense and construction are the preventive system of human body for anti-evil invasion, which related with microcirculatory system. .The infectious diseases caused by wind-cold evil in Shang han lun book were divided to three yang diseases and three yin diseases. The chronic infectious diseases caused by the pathway of body surface into visceral organ tissue, which is called Greater yang disease. From Greater yang disease internally transferred Yang ming or disease evil through by mouth direct into gastr-intestinal tract caused stomach domain repletion, which is called Yang ming disease. Pathogen from the lesion area of Greater yang disease or Yang ming disease, through the blood stream enter the lesion area of Lesser yang disease and caused organ and tissue inf1ammatory infiltration, which is called Lesser yang disease. On the other hand, the three yin disease most caused from Greater yang disease which organ function failure or decompensate. The Lesser yin disease is stand of shock or heart failure. The Greater yin disease is stand of the liver decompensate. The Reverting yin disease included acute and chronic renal failure syndrome.