This study was the first to conduct a survey of traditional medicine doctors engaged in public health works regarding the prevention and management of AEs utilizing traditional medicine modalities before and after the COVID-19 vaccination. Ninety-seven percent of KMDs who received the vaccine complained of AEs such as muscle pain, fever, pain at the injection site, and fatigue. Moderate AEs were common, and AEs lasted more than 1 d in many cases. Fifteen percent of the participants took herbal medicines before vaccination to prevent AEs, and 57.78% took herbal medicines for post-vaccination management. More than 60% of the PHDKMs stated that they would recommend taking herbal medicines to manage AEs before vaccination and considered that KM treatments for vaccine AEs were helpful in public health.
COVID-19 and traditional medicine
As the pandemic lasted nearly 3 years, COVID-19 has had a tremendous impact on each country's economy and medical status and travel, trade, and restrictions on daily activities. For this reason, policymakers are seeking to return to pre-pandemic status via vaccination; however, a worldwide vaccine shortage has been the issue for all. Up to date, 24.3% of the world population have received at least one dose of a COVID-19 vaccine, and 3.22 billion doses have been administered globally. With regard to the Republic of Korea, 15 million people received their first vaccination, and 5.3 million were finished until June. So far, six vaccines have been approved by the World Health Organization, and four vaccines are being used in Korea. Nucleic acid vaccine of COVID-19, mRNA-1273, was developed by Moderna and the National Institute of Allergy and Infectious Diseases and entered human trial on March 16, 2020. mRNA-1273 received emergency use approval from the United States Food and Drug Administration[25,26]. Another nucleic acid vaccine, BNT162b2, was developed by Pfizer and BioNTech and a phase III trial has been completed. Non-replicating viral vector vaccines also get approval. The Oxford Jenner Institute and AstraZeneca developed ChAdOx1 nCoV-19 Vaccine (AZD1222) using non-replicating chimpanzee adenovirus containing severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) surface spike. Janssen Pharmaceutical’s vaccine, Ad26, is a single-dose vaccine that shows a safety profile in phase I study and a phase III trial is being conducted.
Common AEs of COVID-19 vaccines include fever, fatigue, headache, coldness, nausea, diarrhea, and muscle pain. Severe and rare AEs include anaphylaxis, thrombosis with thrombocytopenia syndrome, myocarditis, and pericarditis[8,10]. Anxiety-related symptoms, including syncope, were also reported after vaccination. According to an online survey conducted in Poland, 78% (1253) of vaccinated respondents reported soreness at injection sites, 46.6% (746) limb pain, 30% (490) fatigue, and 24.5% (392) injection site swelling. Vaccine refusal due to AEs is a long-known threat to infectious disease management in the field of public health. In the United States, myocarditis has been reported after vaccination of COVID-19 mRNA vaccine to healthy soldiers, and anaphylaxis has also been observed after Pfizer-BioNTech COVID-19 vaccine inoculation. However, the number of 11.1 cases per million doses is small. It is well known that the misinformation and fear of AEs negatively affect the rate of accepting vaccination. Recently, countries such as Romania have also struggled to increase coverage because of COVID-19 vaccine rejection due to an outdated trend of vaccine rejection. Thus, developing public health strategies to prevent and manage vaccine AEs effectively is essential to increase COVID-19 vaccination rates and return to the pre-COVID era. Through this study, it was possible to explore the awareness and attitude of KMDs working in public health in managing AEs of vaccination utilizing KM. Most of the participants in this study reported the AEs of COVID-19 vaccination. It is vital to note that the response rate of recommending herbal medicine treatment for effective management of vaccine AEs was high.
Sanghanron (Shang Han Lun, Treatise on Cold Damage and Miscellaneous Diseases), the oldest traditional Chinese medicine book, is a book to treat infectious diseases (refer to Sanghanron), and until recently, traditional medicine has been used to treat various infectious diseases in East Asia. Various experimental studies and clinical studies have been conducted to elucidate the mechanism of herbal medicines in the treatment of COVID-19, and the results of the studies are being actively used in the treatment of COVID-19 in China. Studies on herbal medicines to prevent AEs of vaccines or enhance vaccines' effectiveness are also being reported in East Asia. In this study, no side effects were reported after taking herbal medicine. One of herbal medicine's most known side effects is drug-induced liver damage. However, the risk of drug-induced liver damage from herbal medicines prescribed by professionals like KM doctors is around 1%, and most recover when they stop taking them[36-40]. From this point of view, this study is meaningful in that it confirmed the consensus on the AEs experienced during the vaccination process and management experience with herbal medicines through an online survey among the PHDKMs. The participants were highly inclined to recommend KM treatments to the general public. In addition to the existing experimental and clinical evidence of the effects of herbal medicines on vaccine AEs, it was confirmed through the experiences and opinions of experts that herbal medicines can be used to manage AEs of vaccines. Hence, these data can be used as fundamental research data on the role of KM in establishing a strategy to increase the vaccination rate by reducing vaccine rejection. However, there is no consensus on the types of recommended herbal medicines; therefore, additional research is much needed. Further research is also needed to explore how many clinical effects herbal medications have been used in the management of AEs and how they affect immune formation when combined with vaccines.
Limitation, recommendation, and future perspective
This study has several strengths. First, to our knowledge, this study is the first to report the use of KM treatment after vaccination in Korea. Second, previous studies reported that AEs were severe in people in the 20s and 30s rather than in older people. This study's data perhaps could be used in a homogeneous population with relatively severe AEs. Third, this study was conducted on KMDs working on public health; it has the advantage of obtaining fairly accurate data compared to other groups because of a high understanding of the types of AEs. There are also some limitations to this study. First, this research was based on self-reported AEs, which would have been biased and may not represent all KMDs. In addition, a bias may exist that gives more favorable answers to KM due to the fact that the participants were KMDs. Nonetheless, raw data itself is meaningful because it is the significant data that shows the public health workers' awareness of KM interventions. Since this survey was conducted after vaccination, the reported AEs could be overestimated or underestimated. Third, participants were recruited by the APKOM, further studies are needed to reflect the attitude of all KMDs. Lastly, when this survey was conducted on April 2021, there was no distinction between vaccination according to age according to national guidelines, and KMDs who were in their 20s were vaccinated with AZ vaccine. However, in May 2021, the same KMDs received the Pfizer-centered vaccinations due to a change in the guidelines. Finally, the study period was short (11 d), the number of people who responded to the questionnaire was less than 100, and the study design itself had intrinsic limitations in which no control group was established. Nevertheless, this study has the strength of being the first exploratory survey that can confirm the attitudes of using KM interventions after vaccination from KMDs.
Also, in this study, there was no statistically significant difference in the incidence of AEs between the group taking herbal medicine and the group taking Western medicine (14 herbal and 13 western medicine) before vaccination to prevent AEs. However, this study is not quantitatively or clinically confirming the difference in AEs after administration, but a questionnaire about the attitudes toward vaccines of traditional medicine practitioners in public health. Because the number of samples is small to verify the difference in the occurrence of AEs after administration, and the power is low accordingly, it is not possible to make a definitive conclusion about the occurrence of AEs after administration as a result of this study. In this regard, further studies are needed to figure out the clinical outcomes of usage of KM treatment for the post-vaccination AE management. From a clinical perspective, PHKMDs recommend herbal medicine and acupuncture for the AEs of vaccination management. In order to increase the vaccination rate when a new infectious disease is prevalent, herbal medicine or acupuncture should be actively used to manage the side effects of vaccination. In terms of clinical research, prospective, controlled, and multi-site clinical studies are needed to explore which kind of herbal prescription is effective for each side effect.