此由邪气与卫气俱行于风府，而有时相失不相得，故邪气内搏五脏，则道远气深，故其
行迟，不能与卫气偕出，是以间日而作也。
夫疟皆生于风。风者，阳气也，阳主热，故卫气每至于风府，则腠理开，开则邪入，邪
入则病作。先伤于风，故发热而后寒栗。
夫瘅疟者，肺素有热，气盛于身，厥逆上冲，中气实而不外泄，因有所用力，腠理开，
风寒舍于皮肤之内，分肉之间而发。发则阳气盛，阳气盛而不衰则病矣。其气不及之阴，故
但热而不寒，热气内藏于心，而外舍分肉之间，令人消铄脱肉，故命曰瘅疟。其状，但热不
寒，阴气先绝，阳气独发，则少气烦惋，手足热而呕也。
此病生于岭南，带山瘴之气。其状，发寒热，休作有时，皆由山溪源岭嶂湿毒瓦斯故也。
其病重于伤暑之疟。
痰实疟者，谓患人胸膈先有停痰结实，因成疟病，则令人心下胀满，气逆烦呕也。
夫疟者，风寒之气也。邪并于阴则寒，并于阳则热，故发作皆寒热也。
此由寒气并于阴则发寒，风气并于阳则发热，阴阳二气更实更虚，故寒热更往来也。
这是由于邪气与卫气一同运行至风府穴，但有时两者失去协调、不能同步，因此邪气向内搏击五脏。因为路径遥远、病位深在，所以邪气运行迟缓，无法与卫气同时外出，这就是疟疾每隔一天发作一次的原因。
大凡疟疾都是由风邪引起的。风属于阳气，阳主热，所以当卫气运行到风府穴时，腠理（皮肤纹理及汗孔）就会张开；腠理张开则邪气得以侵入，邪气侵入则疾病发作。因为先受到风邪伤害，所以表现为先发热而后出现寒战。
所谓瘅疟（一种以高热为主要特征的疟疾），是因为患者肺中素有积热，体内气机亢盛，气逆向上冲撞，中焦之气充实而不能向外宣泄。加上因用力劳作导致腠理开张，风寒之邪便停留在皮肤之内、分肉（肌肉间隙）之间而发病。发病时阳气亢盛，若阳气亢盛而不衰退，疾病就会持续。由于邪气未能波及阴分，所以只发热而不恶寒。热气内藏于心，外留于分肉之间，使人肌肉消瘦、身体枯槁，因此命名为瘅疟。其症状表现为只有发热而没有恶寒，阴气先衰竭，阳气独自亢盛，导致气短、心中烦闷懊恼，手足发热并伴有呕吐。
这种病产生于岭南地区，带有山间的瘴疠之气。其症状为发作时忽冷忽热，且有固定的间歇时间，这都是由山溪源岭间潮湿毒气所致。这种病的病情比伤暑引起的疟疾更为严重。
痰实疟，是指患者胸膈部位原本就有停聚的痰饮凝结成实，因而形成疟疾，导致心下（胃脘部）胀满，气机上逆、心烦且呕吐。
大凡疟疾，是由风寒邪气引起的。邪气并入阴分则表现为寒，并入阳分则表现为热，所以发作时都伴有寒热交替。
这是由于寒气并入阴分则发寒，风气并入阳分则发热，阴阳二气虚实交替变化，所以寒热往来交替出现。
这是由于阴阳邪气相互搏结，阳气虚弱则阴气偏胜，阴气偏胜则生寒。寒气从内部发出并向外部扩散，导致内外皆寒，所以在疾病发作时仅表现为战栗和咬牙鼓动腮颊。
This occurs because the pathogenic factor and the Wei Qi (Defensive Qi) travel together to the Fengfu acupoint (GV16), but at times they lose coordination and fail to move in sync. Consequently, the pathogenic factor internally assaults the Zang organs. Due to the long pathway and deep location of the disease, its movement is slow; it cannot exit simultaneously with the Wei Qi. This is why the condition manifests every other day.
Generally, all malaria arises from Wind pathogens. Wind belongs to Yang energy, and Yang governs heat. Therefore, whenever the Wei Qi reaches the Fengfu acupoint (GV16), the Couli (pores and interstices of the skin) open. When the Couli are open, pathogens enter; once pathogens enter, the disease manifests. Because the body was initially injured by Wind, fever appears first, followed by chills.
The so-called Dan Malaria (a type of malaria characterized by high fever) occurs because the lungs inherently possess accumulated heat, causing Qi to be excessive throughout the body. There is rebellious Qi rushing upward, and the Qi in the Middle Jiao is full but fails to vent outward. Due to physical exertion that causes the Couli to open, Cold-Wind pathogens lodge within the skin and between the muscles (Fenrou). Upon manifestation, Yang Qi becomes excessive. If this excessive Yang Qi does not decline, the disease persists. Since the pathogenic Qi does not reach the Yin aspect, there is only fever without chills. The hot Qi stores internally in the Heart and externally lodges between the muscles, causing emaciation and wasting of flesh; thus, it is named Dan Malaria. Its presentation involves only fever without chills; Yin Qi is exhausted first, while Yang Qi acts alone and excessively, resulting in shortness of breath, mental restlessness and vexation, heat in the hands and feet, and vomiting.
This disease originates in the Lingnan region, carrying the miasmic Qi of the mountains. Its symptoms include alternating chills and fever with regular intervals. This is caused by the damp-toxic vapors found in mountain streams and ridges. The severity of this illness exceeds that of malaria caused by summer-heat injury.
Tan Shi Malaria (Phlegm-Stasis Malaria) refers to a condition where the patient already has stagnant phlegm consolidated in the chest and diaphragm prior to onset. This leads to malaria, causing distension and fullness below the heart (epigastrium), rebellious Qi, mental irritability, and vomiting.
Generally, malaria is caused by Cold-Wind pathogens. When pathogens merge into the Yin aspect, cold manifests; when they merge into the Yang aspect, heat manifests. Therefore, attacks always involve both cold and heat.
This occurs because Cold Qi merging into Yin induces chills, while Wind Qi merging into Yang induces fever. The Yin and Yang Qi undergo alternating excess and deficiency, leading to the alternating recurrence of chills and fever.
This results from the mutual binding of Yin and Yang pathogens. When Yang is deficient, Yin prevails; when Yin prevails, cold generates. Cold emanates from the interior and merges with the exterior, causing both interior and exterior to be cold. Thus, during an attack, the patient experiences only shivering and clenching of the jaw.
For malaria that persists for a long time without resolution, both the exterior and interior become deficient. The invading pathogens have not dispersed, and the True Qi has not recovered. Therefore, although the disease may temporarily subside, any slight exertion will trigger a recurrence.