This is a multi-center, outcome assessor-blinded, practical randomized controlled trial, aiming to compare the actual clinical effectiveness of individualized traditional Chinese medicine and conventional Western medicine in the treatment of long COVID.

Totally 162 patients with long COVID recruited into the study will be randomly assigned to the traditional Chinese medicine treatment group or the Western medicine control group. Patients in the treatment group will receive individualized TCM syndrome differentiation treatment, and patients in the control group will receive conventional Western medicine symptomatic treatment from general Western medicine practitioners for 4 weeks. All patients were followed up once a week (±2 days) during treatment period and followed up by 4 weeks (±2 days) after the treatment. Outcome measurements will be conducted at baseline, the end of treatment (week 4 ±2 days) and the follow-up visit (week 8 ±2 days).

The novel coronavirus has caused a global pandemic since the end of 2019. As of November 27, 2022, 637 million people have been diagnosed worldwide and more than 6 million people have died. Studies have reported that about 10%-20% of people will continue to have some post-infection symptoms after being infected with the new coronavirus. The World Health Organization (WHO) named it the Post COVID-19 Condition or Long COVID. The main symptoms of Long COVID include severe fatigue, shortness of breath, heart damage (such as myocarditis), cognitive impairment, sleep disturbance, post-traumatic stress disorder syndrome, muscle pain, decreased concentration, headache, impaired taste, and smell, etc.

In the face of the ongoing epidemic and more and more people being infected, people are increasingly concerned about the long-term impact of the new coronavirus infection. At present, western medicine is trying to adopt symptomatic treatment for some main symptoms of COVID-19. In addition, people are also trying many non-drug treatments, such as exercise, pulmonary rehabilitation training, cognitive behavioral therapy, etc.

Traditional Chinese medicine (TCM) has been strongly involved in the treatment and prevention of COVID-19 and the recovery of COVID-19 infection in the early stages of the epidemic. In order to cope with the fifth wave of the epidemic in Hong Kong, in April 2022, the Chinese government's Anti-epidemic Chinese Medicine Expert Group in Hong Kong launched the "Guidelines on the Rehabilitation of Traditional Chinese Medicine during the Recovery Period of Coronavirus Disease 2019 (Trial Version)". However, there is a lack of clinical research evidence that has practical guiding value for the TCM syndrome diagnosis and medication in long COVID patients. Secondly, there is a lack of reliable research evidence on the clinical effectiveness of individualized Chinese medicine treatment of long COVID. Thirdly, there is a lack of large-scale research data on patients with long COVID from clinical treatment. Fourthly, there is a lack of comparative research evidence between traditional Chinese medicine and conventional Western medicine.

Therefore, this study will be conducted in order to understand the possible advantages or disadvantages of traditional Chinese medicine compared with Western medicine; improve the efficacy of traditional Chinese medicine in the treatment of long COVID; and promote the application of traditional Chinese medicine in the field of long COVID treatment.

Inclusion Criteria:

• Chinese subjects with age between 6 and 80 years old;
• For those who have recovered from COVID-19, it has been more than 28 days since the date of diagnosis (the diagnosis is confirmed by rapid antigen test or positive nucleic acid test of deep throat saliva or nose/throat swab);
• The average score of the modified COVID-19 Yorkshire Rehabilitation Scale (C19-YRSm) is above 2 (i.e. above the moderate level).

Exclusion Criteria:

• People who have not been infected with COVID-19;
• People who are still positive for COVID-19;
• Known history of some certain serious medical disease, which is in an unstable state or even affects basic survival, such as cardiovascular disease, liver or renal dysfunction, diabetes, cancer, cerebrovascular disease, blood disorders;
• Known impaired hematological characteristics or impaired liver/kidney function;
• People with mild cognitive impairment, that is, those whose age/education matching percentile in the score of the Hong Kong version of Montreal Cognitive Assessment (HK-MoCA) is lower than 16; or those who cannot truthfully fill out the questionnaire due to mental and psychological factors;
• Have used any drugs or other treatment methods for the treatment of COVID-19 in the past week, such as acupuncture, massage, scraping, cupping, etc.;
• Known history of allergy to any traditional Chinese medicine.

The outcome data collectors are blinded throughout the study. Patients will be specifically instructed not to disclose specific treatment received to outcome data collectors.