时疫恶寒与风、寒、暑、湿诸证不同，诸证恶寒无时而势不甚，时疫恶寒有时而势甚；恶寒之后，必见发热，
热时自热而不觉寒，寒时自寒而不觉热，非若诸证恶寒发热之相兼也。
时疫恶寒传里之后少，在表之时多，而辨气、色、神、脉、舌苔与发热同，但有浅、深、虚、实之异。邪浅
而在表者，恶寒之时少于发热，治法方药同于发热，而以解表为主。邪在半表半里者，寒热往来如疟状，治法方药
亦同发热。邪深入里，失于攻下，而热深厥深，反欲拥被向火，恶寒而不发热，或热亦微，甚则四肢反厥，此虽恶
寒，实非寒也，乃阳气为邪所郁而不通，以通郁为主，达原饮、大柴胡汤、三承气汤选用，使里气通而郁阳发，反
大热而烦渴也。此证在恶寒时最难辨其为热，须于九窍察之。如目大小 赤，鼻孔干，唇红，舌苔黄黑燥，耳鸣或
聋，小便黄、赤、涩、痛，大便燥结，或稀黄极臭，或鲜血，或心下至少腹有痛不可按处，此皆热深阳郁之象。
大抵周身皆见冷证，一、二处独见热证，反当以热证为主，反此亦然，乃辨寒、热、真、假之机要也。余所见时疫不
下数千，里证恶寒者，百中一、二，即四肢厥逆，爪甲青紫，询其所苦，亦不恶寒，此可得其概矣。
至若本系时疫热证，因其人平素虚损衰老，及大病之后，用攻伐寒凉太过，至汗出不止，呕利俱作，四肢微厥，
六脉细濡而恶寒，为阳虚，乃攻伐太过所致，当以参， 、苓、术为主。寸口脉微者，佐以升、柴；尺脉微者，佐以
桂、附。须知虽属阳虚，却从热证来，而阴必亏，桂、附亦不可过用，当佐以护阴药为妙，如白芍、麦冬、五味之
类。此证温补略缓，及温补不到，必死；或过用温补，阳虽回而阴竭，亦死，此处不可不斟酌至当。又有宣伐太
过，而成虚证之恶寒；寒凉太早，而成实证之恶寒。以疫
邪方伏于募原，未经传变之时，胸膈必多痰滞。有见其烦躁而遽用知、膏、芩、连者；有因其作渴而遽用生地、麦
冬者，有病者自认火证而恣啖冷水、西瓜、梨、荠太早者，皆能抑郁阳气，壅闭邪热，热遏于中、下二焦，冷
物、停痰滞于上焦，每每见恶寒证。遇此惟以宣导痰滞为主，痰滞通则恶寒自止。不可过温，致下焦瘀热、蓄血、
斑黄、呃逆而死；不可清凉，致胸腹痞闷而危。宜用草果、浓朴、槟榔、木香、半夏、苍术、莱菔、苓、泽导
痰、开滞、逐水。痰滞水去，则恶寒止而热证见，随其传变以施凉解攻利之剂，乃有效也。此法特救药误，
非治正病耳。
总之风寒以恶寒为重，时疫以恶寒为轻。多有初起恶寒，一、二日不治，邪气传变，而恶寒自已者。与其误
治，毋宁俟之，若误认恶寒为真寒，用辛温之药发散，未有不增其病势者也。
时疫（瘟疫）的恶寒症状与风、寒、暑、湿等其他病证引起的恶寒不同。其他病证的恶寒没有特定的时间规律，且病情程度不重；而时疫的恶寒有特定的发作时间，且病情严重。在恶寒之后，必定会出现发热。发热时只感到热而不觉得冷，发冷时只感到冷而不觉得热，不像其他病证那样恶寒和发热同时出现。
时疫的恶寒传变入里的情况较少，停留在体表的情况较多。辨别时疫恶寒与发热的方法相同，主要观察气色、神态、脉象、舌苔，区别仅在于病情的浅深、虚实有所不同。邪气浅而在体表的，恶寒的时间少于发热的时间，治疗方法与方药同于治疗发热，但以解表为主。邪气在半表半里的，出现寒热往来像疟疾一样的症状，治疗方法与方药也同于治疗发热。
邪气深入体内，如果延误了攻下法的治疗，会导致热越深四肢厥冷越严重（热深厥深），反而想要盖着被子靠近火源，表现为恶寒而不发热，或者发热也很轻微，甚至四肢反而厥冷。这虽然表现为恶寒，但实际上并非真正的寒证，而是阳气被邪气郁结阻滞而不能通达。治疗应以疏通郁结为主，选用达原饮、大柴胡汤、三承气汤，使里气通畅而郁结的阳气发散出来，反而会出现大热、烦躁和口渴的症状。这种证候在恶寒阶段最难辨别其本质为热证，必须通过观察九窍来诊断。例如：眼睛发红，鼻孔干燥，嘴唇红润，舌苔黄黑且干燥，耳鸣或耳聋，小便黄、赤、涩、痛，大便燥结，或稀黄极臭，或便鲜血，或从心窝到小腹有疼痛且不可按压的部位，这些都是热邪深重、阳气郁结的表现。
大体上，如果周身都表现出冷证，唯独一两个部位表现出热证，反而应当以热证为主要判断依据；反之亦然，这是辨别寒热、真假的关键要点。我所诊治的时疫患者不下数千例，其中表现为里证恶寒的，一百个中只有一两个。即使是四肢厥逆、指甲青紫的患者，询问其痛苦之处，他们也不觉得恶寒，由此可以概知时疫恶寒的大致情况。
至于原本就是时疫的热证，因为患者平时身体虚弱衰老，以及大病之后，使用攻伐和寒凉药物太过分，导致汗出不止，呕吐和下利同时发生，四肢轻微厥冷，六脉细弱濡软且伴有恶寒，这是阳虚证，是由攻伐太过造成的。治疗当以人参、茯苓、白术为主。如果寸口脉微弱，辅助使用升麻、柴胡；尺脉微弱，辅助使用肉桂、附子。需要知道虽然属于阳虚，但却是从热证发展而来，阴液必然亏损，所以肉桂、附子也不可以过度使用，最好辅助使用保护阴液的药物，如白芍、麦冬、五味子之类。此证温补的速度要略微缓慢，如果温补不到位，必死无疑；如果过度使用温补，阳气虽然恢复但阴液枯竭，也会死亡，此处不可不斟酌得当。又有因宣散攻伐太过，而形成虚证性质的恶寒；或因过早使用寒凉药物，而形成实证性质的恶寒。
当疫邪刚刚潜伏在募原（膜原），尚未发生传变的时候，胸膈部位往往多有痰浊停滞。有的医生见到患者烦躁就急忙使用知母、石膏、黄芩、黄连；有的医生因为患者口渴就急忙使用生地、麦冬；有的患者自己认为是火证而过早大量食用冷水、西瓜、梨、荠菜等，这些做法都能抑制阳气，壅闭邪热，使热邪郁遏在中焦和下焦，而冷物、停痰滞留在上焦，常常出现恶寒证候。遇到这种情况，只能以宣通疏导痰浊停滞为主，痰浊停滞一通，恶寒自然停止。不可过度温补，以免导致下焦瘀热、蓄血、发斑发黄、呃逆而死；也不可过于清凉，以免导致胸腹痞闷而危及生命。适宜使用草果、厚朴、槟榔、木香、半夏、苍术、莱菔子、茯苓、泽泻来导痰、开滞、逐水。痰浊停滞和水饮去除后，恶寒停止而热证显现，随后根据其传变情况施以清凉解表或攻下通利的方剂，才能见效。这种方法专门用于救治因用药错误导致的病症，并非治疗时疫的正治之法。
总之，风寒病以恶寒为重，时疫病以恶寒为轻。很多时疫初起时有恶寒，经过一两天如果不加干预，邪气传变，恶寒就会自行消失。与其误治，不如等待时机。如果误将恶寒认作真寒，使用辛温药物发散，没有不加重病情的。
The aversion to cold (Ehan) in plague-epidemic diseases differs from that caused by wind, cold, summerheat, and dampness. In other conditions, aversion to cold occurs without specific timing and is not severe; whereas in plague-epidemics, it occurs at specific times and is severe. Following aversion to cold, fever must appear. During fever, one feels only heat without cold; during chills, one feels only cold without heat. This is unlike other conditions where aversion to cold and fever occur simultaneously.
In plague-epidemics, aversion to cold rarely transmits inward but often remains on the exterior. The differentiation relies on observing qi, complexion, spirit, pulse, and tongue coating, similar to differentiating fever, with differences only in depth, superficiality, deficiency, and excess. When the pathogen is shallow and on the exterior, the duration of aversion to cold is shorter than that of fever. The treatment method and formulas are the same as for fever, but primarily focus on releasing the exterior (Jiebiao). When the pathogen is in the half-exterior half-interior stage, alternating chills and fever resembling malaria occur; the treatment method and formulas are also the same as for fever.
When the pathogen penetrates deeply into the interior, and purgation is delayed, deep heat leads to deep extremity cold (Re Shen Jue Shen), manifesting as a desire to cover oneself with blankets and approach fire, presenting as aversion to cold without fever, or with only slight fever, and even cold extremities. Although this presents as aversion to cold, it is not true cold; rather, it is yang qi constrained and blocked by the pathogen. Treatment should focus on unblocking the constraint, selecting Da Yuan Yin (Origin-Reaching Decoction), Da Chai Hu Tang (Major Bupleurum Decoction), or the three Cheng Qi Tangs (Three Order-Regulating Decoctions). This allows the interior qi to flow freely and the constrained yang qi to disperse, potentially resulting in high fever, restlessness, and thirst. This condition is most difficult to identify as heat during the phase of aversion to cold; one must examine the nine orifices. Signs include red eyes, dry nostrils, ruddy lips, yellow-black dry tongue coating, tinnitus or deafness, yellow/red/astringent/painful urination, dry constipation, or loose yellow foul-smelling stool, bloody stool, or tenderness and inability to press from the epigastrium to the lower abdomen. These are all signs of deep heat and constrained yang. Generally, if the whole body shows cold signs but one or two areas show heat signs, one should prioritize the heat diagnosis; conversely, if the whole body shows heat but one or two areas show cold, one should prioritize the cold diagnosis. This is the key to distinguishing between true and false cold and heat. Among the thousands of plague cases I have treated, only one or two out of a hundred presented with interior aversion to cold. Even those with cold extremities and cyanotic nails reported no subjective feeling of cold when asked about their discomfort. This provides a general overview.
However, if the original condition was a heat-type plague, but due to the patient's inherent deficiency, old age, or excessive use of purgative and cooling drugs after a major illness, leading to incessant sweating, simultaneous vomiting and diarrhea, mild cold extremities, fine and soggy pulses throughout, and aversion to cold, this is Yang Deficiency caused by excessive attacking. Treatment should prioritize Ren Shen (Ginseng Radix et Rhizoma), Fu Ling (Poria), and Bai Zhu (Atractylodis Macrocephalae Rhizoma). If the cunkou (radial artery at wrist) pulse is faint, assist with Sheng Ma (Cimicifugae Rhizoma) and Chai Hu (Bupleuri Radix); if the chi (distal radial artery) pulse is faint, assist with Gui Zhi (Cinnamomi Ramulus) and Fu Zi (Aconiti Lateralis Radix Praeparata). Note that although this is Yang Deficiency, it originated from a heat condition, so yin must be deficient. Therefore, Gui Zhi and Fu Zi should not be overused; it is advisable to assist with yin-nourishing herbs such as Bai Shao (Paeoniae Radix Alba), Mai Dong (Ophiopogonis Radix), and Wu Wei Zi (Schisandrae Chinensis Fructus). The warming and tonifying action here should be gradual. If warming and tonifying are insufficient, death ensues; if overused, although yang may return, yin exhaustion will cause death. Thus, careful deliberation is essential. There are also cases of aversion to cold resulting from deficiency due to excessive purgation/dispersal, or aversion to cold resulting from excess due to premature use of cold/cooling drugs.
When the epidemic pathogen is just latent in the Mu Yuan (Membrane Source) and has not yet transmuted, there is often phlegm stagnation in the chest and diaphragm. Some physicians, seeing irritability, hastily use Zhi Mu (Anemarrhenae Rhizoma), Shi Gao (Gypsum Fibrosum), Huang Qin (Scutellariae Radix), and Lian Qiao (Forsythiae Fructus - *Note: Text says 'Gao', likely referring to Gao or similar bitter cold herbs, usually interpreted as Gao Ben or similar in context of Qing Re, but strictly 'Gao' might be a typo for 'Shi Gao' or generic term. Given context 'Zhi, Gao, Qin, Lian', 'Gao' likely refers to Shi Gao or similar. I will translate as Gypsum or similar cold herb*). Others, seeing thirst, hastily use Sheng Di Huang (Rehmanniae Radix) and Mai Dong. Patients who self-diagnose fire syndromes and consume cold water, watermelon, pear, or shepherd's purse too early can also suppress yang qi and obstruct pathogenic heat. This traps heat in the middle and lower jiao, while cold substances and retained phlegm stagnate in the upper jiao, frequently causing aversion to cold. In such cases, treatment must focus on promoting the dispersion and guidance of phlegm stagnation. Once phlegm stagnation clears, aversion to cold ceases. Do not over-warm, lest it cause lower jiao blood stasis, heat accumulation, macules, jaundice, and hiccups leading to death; do not over-cool, lest it cause chest and abdominal fullness and danger. Suitable herbs include Cao Guo (Tsaoko Fructus), Hou Po (Magnoliae Officinalis Cortex), Bing Lang (Arecae Semen), Mu Xiang (Aucklandiae Radix), Ban Xia (Pinelliae Rhizoma), Cang Zhu (Atractylodis Rhizoma), Lai Fu Zi (Radish Seed), Fu Ling (Poria), and Ze Xie (Alismatis Rhizoma) to guide phlegm, open stagnation, and drain water. Once phlegm, stagnation, and water are removed, aversion to cold stops and heat signs emerge. Subsequently, apply cooling, resolving, or purgative formulas according to the transmission pattern for effectiveness. This method specifically treats iatrogenic errors, not the primary disease itself.
In summary, in wind-cold diseases, aversion to cold is heavy; in plague-epidemics, it is light. Many cases start with aversion to cold, which resolves spontaneously after one or two days as the pathogen transmutes if untreated. It is better to wait than to mistreat. Mistaking aversion to cold for true cold and using acrid-warm dispersing drugs will invariably exacerbate the condition.