景岳子曰∶痘之与疹，原非一种，虽痘之变态多证，而疹之收敛稍易，然疹之甚者，其势凶危
，亦不减于痘，最为可畏，盖疹毒痘毒，本无异也。第古人重痘而忽疹，多不详及，使后人无所宗
法，余实怅之。自得罗田万氏之刻，见其理透法精，鄙念斯慰。今悉从其训，备述于此，虽其中稍
有裁订，亦不过正其疑似，详具未详耳。使此后患疹者，幸获迷津之指南，亦以见万氏之功为不少
矣。
疹者，痘之末疾，惟二经受证，脾与肺也，内应于手足太阴，外合于皮毛肌肉，是皆天地间
戾不正之气，故曰疹也。然其名目有异，在苏松曰沙子，在浙江曰醋子在江右湖广曰麻，在山陕曰
肤疮、曰糠疮、曰赤疮，在北直曰疹子。名虽不同，其证则一。但疹在痘前者，痘后必复疹，惟痘
后出疹者，方为结局。
万氏曰∶疹以春夏为顺，秋冬为逆，以其出于脾肺二经，一遇风寒，势必难出，且多变证，故
于秋冬为不宜耳。夫天行不正之气，致为人之疡疹，然古人于痘疹二字，始终归重于痘，并不分别
疹为何物，岂可以二证归于一证耶？想当时重痘不重疹，故尔略之，致使后人不得心法，因而害事
者，往往有之。今以吾家四代传流，以及今日心得之法，开载于后，用此应病，定不差矣。敢有毫
厘隐匿，天其鉴之。
景岳先生说：痘疮和疹子，原本就不是同一种病。虽然痘疮的变证很多，但疹子的消退相对容易；然而病情严重的疹子，其势头凶险危急，也不亚于痘疮，是最令人畏惧的。大概是因为疹毒和痘毒，本质上是相同的。只是古人重视痘疮而轻视疹子，大多没有详细论述，导致后人没有遵循的法度，我对此深感遗憾。自从得到罗田万氏刻印的著作，看到其中医理透彻、治法精妙，我的忧虑才得以安慰。现在完全遵循他的教导，在此详尽叙述，虽然其中稍有裁断修订，也不过是纠正似是而非之处，将不详备的地方补充详细罢了。希望此后患疹的人，有幸获得迷途中的指南，这也足以显示万氏先生的功劳不小了。
疹子，是痘疮的轻浅之疾，主要涉及脾经和肺经这两条经络的症状，内部对应手足太阴经，外部合应于皮毛肌肉。这都是天地间乖戾不正之气所致，所以称为疹。然而它的名目有所不同，在苏州、松江地区叫“沙子”，在浙江叫“醋子”，在江西、湖广地区叫“麻”，在山陕地区叫“肤疮”、“糠疮”或“赤疮”，在北直隶地区叫“疹子”。名字虽然不同，但病症表现是一致的。但是，如果在出痘之前先出疹，那么出痘后必定还会再出疹；只有出痘之后才出疹的，才算作结局（痊愈）。
万氏说：疹子在春夏季节出现为顺证，在秋冬季节出现为逆证，因为它源于脾肺二经，一旦遇到风寒，势必难以透发，且容易变化出其他证候，所以在秋冬季节是不适宜的。天地间的乖戾不正之气，导致人发生疡疹，然而古人在痘疹这两个字上，始终着重于痘疮，并不分别疹子究竟是什么，怎么能把两种证候归结为一种呢？想当时重视痘疮而不重视疹子，所以略去了对疹子的论述，致使后人得不到心传之法，因而造成危害的事情，往往有发生。现在将我家族四代传承以及今日心得的方法，记载在下面，用这些方法来应对疾病，一定不会出差错。如果敢有丝毫隐瞒，上天会鉴察的。
Jingyue said: Variola (smallpox) and exanthema (measles/rash) are originally not the same disease. Although variola presents with many variations and syndromes, exanthema is slightly easier to resolve; however, severe cases of exanthema can be equally ominous and critical, which is most fearsome. This is because the toxins of exanthema and variola are essentially the same. It is just that ancient physicians valued variola but neglected exanthema, rarely discussing it in detail, leaving later generations without a standard to follow, which I deeply regret. Since obtaining the printed work by Mr. Wan from Luotian, seeing its profound medical principles and refined treatment methods, my concerns have been alleviated. Now, following his teachings completely, I narrate this in detail here. Although there are slight revisions and adjustments, they merely correct ambiguous points and elaborate on previously unspecified details. May those who suffer from exanthema in the future find a guide through their confusion, thereby acknowledging the significant merit of Mr. Wan.
Exanthema is a mild form of variola, primarily involving symptoms of the Spleen and Lung meridians. Internally, it corresponds to the Hand and Foot Taiyin meridians, and externally, it combines with the skin and muscles. These are caused by the aberrant and unhealthy qi of heaven and earth, hence called "exanthema." However, its names vary: in Suzhou and Songjiang, it is called "Shazi" (Sand Rash); in Zhejiang, "Cuzi" (Vinegar Seed Rash); in Jiangxi and Huguang, "Ma" (Hemp/Rash); in Shanxi and Shaanxi, "Fuchuang" (Skin Sore), "Kangchuang" (Bran Sore), or "Chichuang" (Red Sore); and in Zhili, "Zhenzi" (Rash Child). Though the names differ, the clinical manifestations are identical. However, if exanthema appears before variola, variola will inevitably reappear after the initial rash; only when exanthema appears after variola does it signify a conclusion (recovery).
Mr. Wan stated: Exanthema appearing in spring and summer is a favorable prognosis (Shun), while appearing in autumn and winter is unfavorable (Ni). Because it originates from the Spleen and Lung meridians, once exposed to wind-cold, it becomes difficult to erupt and is prone to complicated syndromes, making autumn and winter unsuitable seasons for its occurrence. The aberrant qi of nature causes sores and rashes in humans. Yet, ancient physicians always emphasized variola over exanthema, never distinguishing what exanthema actually was. How can two distinct conditions be lumped into one? It seems that at that time, valuing variola over exanthema led to its omission, causing later generations to miss the essential methods, resulting in harm frequently. Now, recording the four generations of family transmission along with my own insights below, these methods applied to diseases will certainly be accurate. If I dare conceal even a slightest detail, may Heaven witness it.