时疫一证，乃天地之厉气流行，沿门盖境，无论老少强弱，触之即病，遂相传染，迥非春温夏热秋凉冬寒之
类也。夫天地间之气，升于春，浮于夏，收于秋，藏于冬，此气之常也。春应温而反寒，夏应热而反凉，秋应凉
而反温，冬应寒而反热，此气之变也。人在气交之中，如鱼在水中，时行不正之气，人受之从口鼻而入，即受毒
邪异气而不自知，迨一发则迅如风火，治之或误时，或误药，即不可救。一传十，十传百，百传千，一误再误，
识时者不免抚膺而三叹，况小儿古称哑科，幼科诸书，皆详于痘疹惊疳吐泻并诸杂证，独时疫则付阙如。若谓小
儿无时疫，凡遇地方疫毒，大人易染，小儿则独不染，于理既不可通。惟所受毒邪虽一，因其气血未足，筋骨柔
脆，故所见之症为异耳。世人但知小儿之身热，安知其头疼身痛乎；但知其不思乳食，心胸膨胀，疑其伤食，安
知疫邪传胃乎；但见呕吐恶心，口渴下利，以
小儿吐泻为常事也，又安知其因时疫毒邪所迫，而为吐为泻乎。小儿一染时疫，延挨失治，瞬即两目上吊，不时
惊搐，肢冷发痉，十指勾曲，甚则角弓反张。幼科对于此症，往往诊其无吐泻者，误认为急惊风；兼吐泻者，误
认为慢惊风其祸伊芳于胡底，因而作时疫解。
小儿当疫毒流行，忽染此病（病状已详时疫解说内，不再赘），古法主发毒邪者，以荆防败毒散（如荆芥、
防风、羌活、独活等十一味。引用生姜）。清毒邪者，以普济消毒饮（如板蓝根、升麻、芩、连等十四味，引用
灯芯），攻毒邪者，以二圣救苦丹（如大黄、皂角二味），水丸。无根水化服。
〔真按〕疫毒须分在表、在里、在阴、在阳，不可错认。又当察四时之气各异，症之轻重，体之强弱，斟酌
施治，方为稳当。兹只列急救一方∶天竺黄三钱，人中黄三钱，直僵蚕（去黑口入药直者为雄）一钱，全蝎一钱，
荆芥穗一钱，防风一钱，水煎，冲当门子一分，调匀服之。
时疫这一病证，是天地间暴戾之气流行所致，波及家家户户、整个区域，无论老少强弱，一旦接触就会发病，随即相互传染，完全不同于春温、夏热、秋凉、冬寒这类普通季节性气候引起的疾病。天地之间的气机，春季升发，夏季浮越，秋季收敛，冬季闭藏，这是气机的正常规律。如果春天本该温暖却反而寒冷，夏天本该炎热却反而凉爽，秋天本该凉爽却反而温暖，冬天本该寒冷却反而温热，这是气机的异常变化。人生活在气机交感的环境中，就像鱼生活在水中一样，时行不正之气通过口鼻侵入人体，人受到毒邪异气的侵袭而不自知，等到发作起来迅速如风火燎原，治疗如果延误时机或用错药物，就无法挽救。病情一传十、十传百、百传千，一再误治，有识之士不免捶胸长叹，更何况小儿在古代被称为“哑科”（因幼儿无法表达病痛），儿科各类书籍，都详细记载了痘疹、惊风、疳积、吐泻以及各种杂症，唯独对时疫病症缺如。如果说小儿不会得时疫，凡是遇到地方性的疫毒，大人容易感染，唯独小儿不染，这在道理上说不通。只是因为所受的毒邪虽然相同，但因其气血尚未充足，筋骨柔弱脆弱，所以表现出的症状有所不同罢了。世人只知道小儿身体发热，哪里知道他头疼身痛呢？只知道他不想吃奶吃饭，心胸胀满，怀疑是伤食，哪里知道是疫邪传入胃腑呢？只见到呕吐恶心、口渴腹泻，认为小儿吐泻是常事，又哪里知道这是因时疫毒邪逼迫，导致呕吐和腹泻呢？小儿一旦染上时疫，拖延失治，转眼就会双眼上吊，不时惊厥抽搐，四肢冰冷发生痉挛，十指弯曲，甚至出现角弓反张（背部肌肉强直痉挛，身体向后反折如弓状）。儿科医生对于这种病症，往往诊断没有吐泻的，误认为是急惊风；兼有吐泻的，误认为是慢惊风，其祸害究竟深重到何种地步，因此撰写《时疫解》一文。
小儿在疫毒流行期间，忽然染上此病（病状已在《时疫解》中详细说明，此处不再赘述），古法主张发散毒邪的，使用荆防败毒散（包含荆芥、防风、羌活、独活等十一味药，引用生姜煎服）。清解毒邪的，使用普济消毒饮（包含板蓝根、升麻、黄芩、黄连等十四味药，引用灯芯草煎服），攻逐毒邪的，使用二圣救苦丹（包含大黄、皂角两味药），制成水丸，用无根水化开服用。
〔真按〕疫毒必须区分是在表、在里、在阴、在阳，不可认错。还应当观察四季之气各不相同，病症的轻重，体质的强弱，斟酌施治，才是稳妥得当。这里只列出急救一方：天竺黄三钱，人中黄三钱，直僵蚕（去除黑口入药，笔直者为雄虫）一钱，全蝎一钱，荆芥穗一钱，防风一钱，用水煎煮，冲入当门子（即麝香）一分，调匀后服用。
The syndrome of seasonal epidemic (Shiyi) is caused by the prevalence of malignant qi from heaven and earth, spreading through neighborhoods and regions. Regardless of age or strength, anyone who comes into contact with it falls ill and transmits it to others. It is entirely different from common seasonal conditions such as Spring Warmth (Chunwen), Summer Heat (Xiare), Autumn Coolness (Qiuliang), or Winter Cold (Donghan). The qi of heaven and earth rises in spring, floats in summer, gathers in autumn, and stores in winter; this is the normal pattern of qi. If spring should be warm but turns cold, summer should be hot but turns cool, autumn should be cool but turns warm, and winter should be cold but turns hot, this is an abnormal variation of qi. Humans exist within the intersection of qi, much like fish in water. When pathogenic irregular qi enters the body through the mouth and nose, one absorbs toxic pathogens and strange qi without realizing it. Once manifested, the disease progresses rapidly like wind and fire. If treatment is delayed or incorrect medicines are used, it becomes incurable. The infection spreads from one to ten, ten to a hundred, and a hundred to a thousand. With repeated errors in diagnosis and treatment, those with insight cannot help but sigh with chest-beating regret. Moreover, children have long been referred to as the "mute department" (Yake) because they cannot verbalize their symptoms. Pediatric texts detail diseases such as smallpox/rubella (Douzhen), convulsions (Jing), malnutrition syndromes (Gan), vomiting and diarrhea (Tuxie), and various miscellaneous disorders, yet they lack descriptions of seasonal epidemics. To claim that children do not suffer from seasonal epidemics—that while adults are easily infected by local epidemic toxins, children alone remain unaffected—is logically untenable. Although the toxic pathogen received may be the same, because children's qi and blood are insufficient and their sinews and bones are soft and fragile, the symptoms presented differ. People only know that children have fever; how can they know the child suffers from headache and body pain? They only know the child refuses milk and food, with a distended chest and abdomen, suspecting food stagnation (Shangshi); how can they know the epidemic pathogen has transmitted to the Stomach? They only see vomiting, nausea, thirst, and diarrhea, assuming these are common occurrences in children; how can they know these result from the pressure of epidemic toxic pathogens causing vomiting and diarrhea? Once a child contracts a seasonal epidemic, if left untreated or treated late, eyes will roll upward, frequent convulsions and spasms will occur, limbs will become cold, tetany will develop, fingers will curl, and in severe cases, opisthotonos (Jiaogongfanzhang) may appear. Pediatric practitioners often misdiagnose cases without vomiting or diarrhea as acute convulsion (Ji Jingfeng), and cases with vomiting and diarrhea as chronic convulsion (Man Jingfeng). The extent of this disaster prompted the writing of "Explanation of Seasonal Epidemics."
When children contract this disease during an epidemic toxin outbreak (symptoms detailed in "Explanation of Seasonal Epidemics," not repeated here), ancient methods for dispersing toxic pathogens recommend Jingfang Baidu San (Cinnamon Twig and Saposhnikovia Decoction, containing 11 herbs such as Schizonepetae Herba [Jingjie], Saposhnikoviae Radix [Fangfeng], Notopterygii Rhizoma et Radix [Qianghuo], and Angelicae Pubescentis Radix [Duhuo], decocted with Zingiberis Rhizoma Recens [Shengjiang]). For clearing toxic pathogens, Puji Xiaodu Yin (Great Relief Detoxification Decoction, containing 14 herbs such as Isatidis Radix [Banlangen], Cimicifugae Rhizoma [Shengma], Scutellariae Radix [Huangqin], and Coptidis Rhizoma [Lian], decocted with Acori Tatarinowii Rhizoma [Dengxin]) is used. For attacking toxic pathogens, Ersheng Jiuku Dan (Two Sages' Saving Kindness Pill, containing Da Huang and Gleditsiae Sinensis Fructus [Zaojiao] in water pills) is prescribed, taken dissolved in wugen shui (water without roots/source).
[True's Commentary] Epidemic toxins must be differentiated as being in the exterior, interior, yin, or yang; misidentification must be avoided. One must also observe the variations of qi across the four seasons, the severity of symptoms, and the strength of the constitution to tailor treatment appropriately, which ensures safety and efficacy. Here, only one emergency rescue formula is listed: Tianzhu Huang (Calamina) 3 qian, Renzhonghuang (Human excrement processed with bamboo) 3 qian, Zhijiangcan (Bombyx Batryticatus [straight form, male]) 1 qian, Quanxie (Scorpio) 1 qian, Jingjie Sui (Schizonepetae Spica) 1 qian, Fangfeng (Saposhnikoviae Radix) 1 qian. Decoct in water, add Dangmenshen (Moschus [Musk]) 1 fen, mix well, and administer.