疟之病候经论载之详矣先寒后热名曰寒疟先热后寒名曰温疟但热无寒名曰瘅疟但寒无热
名曰
牝疟是皆发作有时若邪气中于风府则间日而作邪气客于头项则频日而作气有虚实邪中异所故
有早晚之异然经止论寒温瘅疟所受之因而不及牝疟又论温疟瘅疟所舍之藏而不及寒疟意有互
见发明处学人究阴阳之盛衰深思以得之大抵风者阳气也寒者阴气也先伤于风后伤于寒即先热
后寒先伤于寒后伤于风即先寒后热阴气先绝阳气独发则但热无寒阳气先绝阴气独发则但寒无
热以温疟得之于冬邪气藏于骨髓则知寒疟乃得之于夏邪气客于皮肤腠理之间矣以瘅疟之气实
而不泄且不及于阴则知牝疟乃气虚而泄且不及于阳矣是皆不出于阴阳上下交争虚实更作也又
有挟诸溪毒岚瘴鬼邪之气亦寒热羸瘦延引岁月休作有时久不已变成劳疟或结为 瘕者名曰疟
母至于五脏三阳三阴疟者皆因脏气偏虚故邪气乘而舍之其治法合随其经络灸刺及所用药各不
同后学宜细详之(类编同上)
病有不可补者一曰疟疾二曰狂疾三曰水气四曰香港脚此四疾治得稍愈切不可服暖药以峻补
之如平平补药亦须于本病上有益乃可(医余)
瘕之状虽同而不动者为 其治有法而可推移者名瘕瘕病轻于 瘕不动者必死之候其发
语声
嘶挹言语而不出此人食结在腹其病寒口中常有水出四肢洒洒如疟饮食不能郁郁而痛此食瘕也
疟疾的病候，在经典医论中已有详细记载。发作前先恶寒后发热，称为寒疟；先发热后恶寒，称为温疟；只发热不恶寒，称为瘅疟（热疟）；只恶寒不发热，称为牝疟（冷疟）。这些病症都有固定的发作时间。如果邪气侵入风府穴，则隔日发作；如果邪气客居头项部位，则每日频繁发作。这是因为人体正气有虚有实，邪气侵犯的部位不同，所以发作时间有早有晚。
然而，经典医论只论述了寒疟、温疟、瘅疟的致病原因，而没有涉及牝疟；又论述了温疟和瘅疟所寄居的脏腑，却没有提及寒疟。这大概是作者意在互相补充、阐明道理的地方。学习者应当深入研究阴阳的盛衰变化，深思以领悟其真谛。大体而言，风属于阳气，寒属于阴气。先受风邪后受寒邪，就是先发热后恶寒；先受寒邪后受风邪，就是先恶寒后发热。如果阴气先衰竭，阳气独自亢盛，就会表现为只发热不恶寒；如果阳气先衰竭，阴气独自亢盛，就会表现为只恶寒不发热。
既然温疟是因为冬季感受邪气，邪气潜伏于骨髓所致，那么可以推知寒疟是因为夏季感受邪气，邪气客居于皮肤腠理之间。既然瘅疟是气实而不外泄，且病势不及于阴分，那么可以推知牝疟是气虚而外泄，且病势不及于阳分。这些情况都不超出阴阳上下交争、虚实交替变化的规律。此外，还有夹杂各种溪谷毒气、山岚瘴气、鬼邪之气导致的疟疾，也会出现寒热往来、身体消瘦，病程迁延岁月，时作时止，久治不愈，演变成劳疟，或者结聚形成“瘕”块，称为“疟母”。至于五脏疟以及三阳经、三阴经疟，都是因为脏腑之气偏虚，导致邪气乘虚而入并停留其中。治疗方法应当根据经络不同，采用灸法、刺法以及相应的药物，各不相同。后学者应当仔细详察。（内容同上，出自《类编》）
疾病中有不可使用补法的四种：一是疟疾，二是狂疾，三是水气病，四是脚气病。这四种疾病即使治疗得稍微好转，也切不可服用温热性质的药物进行峻猛进补。即使是平和的补药，也必须对原发病有益处才可以服用。（出自《医余》）
瘕的症状表现虽然相似，但触之不动的是“寢”（此处原文可能有缺字或通假，通常指积块固定不移），可以通过推移改变位置的是“瘕”。瘕病的病情轻于寢。触之不动者，必然是死证的征象。患者发声嘶哑，想说话却说不出来，这是食物结滞在腹中的病证。此病属寒，口中常流出清水，四肢发冷如疟疾状，饮食困难，心中郁闷疼痛，这是食瘕。
The clinical manifestations of malaria (Nue, intermittent fever) have been detailed in classical medical treatises. When chills precede fever, it is called Cold Malaria (Han Nue); when fever precedes chills, it is called Warm Malaria (Wen Nue); when there is only fever without chills, it is called Dan Malaria (Dan Nue, also known as Heat Malaria); and when there is only chills without fever, it is called Pin Malaria (Pin Nue, also known as Cold Malaria). All these conditions occur at regular intervals. If the pathogenic factor invades the Fengfu acupoint (GV16), the attacks occur every other day; if the pathogenic factor lodges in the head and neck region, the attacks occur frequently on a daily basis. This variation in timing arises because the body's vital energy (Qi) varies in deficiency or excess, and the location of pathogenic invasion differs.
However, the classics discuss the etiology of Cold, Warm, and Dan Malaria but omit Pin Malaria; they discuss the viscera involved in Warm and Dan Malaria but omit Cold Malaria. This likely reflects an intent to mutually supplement and elucidate principles. Students should thoroughly investigate the prosperity and decline of Yin and Yang, contemplating deeply to grasp their essence. Generally speaking, Wind belongs to Yang Qi, while Cold belongs to Yin Qi. Injury by Wind first, followed by Cold, results in fever preceding chills; injury by Cold first, followed by Wind, results in chills preceding fever. If Yin Qi is exhausted first and Yang Qi acts alone, there will be fever without chills; if Yang Qi is exhausted first and Yin Qi acts alone, there will be chills without fever.
Since Warm Malaria arises from winter pathogens lodging in the bone marrow, it can be inferred that Cold Malaria arises from summer pathogens lodging between the skin and interstices (Couli). Since Dan Malaria involves excess Qi that does not dissipate and does not affect the Yin aspect, it can be inferred that Pin Malaria involves deficient Qi that leaks and does not affect the Yang aspect. All these cases fall within the pattern of Yin and Yang struggling above and below, with deficiency and excess alternating. Additionally, malaria complicated by various toxic vapors from streams, mountain miasmas, or evil influences may present with alternating chills and fever, emaciation, prolonged duration, irregular onset and cessation, and if unresolved for a long time, may transform into Labor Malaria (Lao Nue) or form a mass known as "Malaria Mother" (Nue Mu). Regarding Malaria of the Five Viscera and the Three Yang and Three Yin meridians, these all arise because the Qi of specific viscera is biased towards deficiency, allowing pathogenic factors to enter and lodge. Treatment methods must vary according to the meridians involved, utilizing moxibustion, acupuncture, and specific herbal formulas accordingly. Later learners should examine this carefully (Same as above, from *Leibian*).
There are four diseases where tonification is contraindicated: one is Malaria, two is Mania (Kuang Ji), three is Water Qi (Shui Qi, edema/fluid retention), and four is Hongxiangjiao (Hongxiangjiao, often referring to beriberi or gouty arthritis). Even if these four diseases show slight improvement after treatment, one must absolutely avoid administering warm-natured herbs for vigorous tonification. Even mild tonifying herbs should only be used if they benefit the primary disease (From *Yiyu*).
Although the manifestations of Jia (soft, movable abdominal mass) appear similar, those that do not move upon palpation are referred to as Qian (hard, fixed abdominal mass). Those that can be displaced or shifted are named Jia. The condition of Jia is milder than that of Qian. A fixed, immobile mass indicates a terminal prognosis. The patient’s voice becomes hoarse, and speech is inhibited or absent; this indicates food stagnation lodged in the abdomen. This disease is characterized by cold, frequent salivation, limbs feeling chilly as in malaria, difficulty eating, mental depression, and pain. This is termed Food Jia (Shi Jia).