Introduction to the Research Results of Coronavirus Disease 2019 Big Data (K-COV-N) and the Corresponding Utilization Plan

Abstract

As part of the effort to establish a scientific basis for quarantine policies aimed at responding to new infectious diseases based on the experience of responding to coronavirus disease 2019 (COVID-19), the Korea Disease Control and Prevention Agency (KDCA) and National Health Insurance Service promoted the establishment of health information big data and signed a business agreement (April 29, 2021). The big data created by combining the KDCA’s COVID-19 confirmed cases and vaccination data with the National Health Insurance Service’s national health information are known as K-COV-N (KDCA Covid-19 NHIS cohort). The big data constructed were opened to the private sector through the National Health Insurance Service’s open platform to promote private research. A cumulative total of 211 cases have been approved since the opening of COVID-19 big data from April 2022 until October 2, 2024, and a total of 30 papers have been published in international journals. The main contents were research results such as COVID-19 infection risk factors, vaccination effects, and long COVID. In addition, after the opening of big data, we held workshops on practical networking for utilizing COVID-19 big data to share analyses and techniques for utilizing the data. Additionally, we established a public-private data analysis network to promote exchanges between practitioners. In addition, we are contributing to the activation of private research by expanding ties with the National Cancer Center and health-information-holding organizations. Accordingly, the KDCA plans to continue opening up infectious disease-related information to develop evidence-based quarantine policies and support expert decision-making.

Key messages

① What is known previously?

Preparing a scientific basis for quarantine policies when responding to new infectious diseases is important.

② What new information is presented?

Big data combining the Korea Disease Control and Prevention Agency’s COVID-19 confirmed case and vaccination data with the National Health Insurance Service’s national health information has been established, released to private researchers from April 2022, and 30 papers are published in international professional journals as of October 2, 2024.

③ What are implications?

Through the activation of expert research, it is necessary to continuously expand the connection with health information holding institutions to provide a scientific basis for future infectious disease policies.

Introduction

Republic of Korea (ROK) has been recognized for its successful response to the coronavirus disease 2019 (COVID-19) through active epidemiological investigations and everyday life quarantines [1,2]. In line with this, the Korea Disease Control and Prevention Agency (KDCA) and the National Health Insurance Service (NHIS) established the scientific foundation of quarantine policies and entered into a business agreement to provide and share data between organizations for the establishment and operation of a COVID-19 big data surveillance system (April 29, 2021) [3]. Additionally, they sought to contribute to actively responding to the spread of COVID-19 to prevent and strengthen the response system in case of future outbreaks of new infectious diseases by utilizing COVID-19 big data.

Results

1. Background and Progress

KDCA and NHIS integrated and linked COVID-19-related data through mutual cooperation, by which they established a big-data analysis environment for infectious disease research unique to ROK by combining COVID-19 full-cycle data and the national health information of NHIS. Big data include information on confirmed cases, such as the date of confirmation; outbreak information, such as the presence of symptoms; and immunization information, such as the number of vaccinations.

In this way, they have been able to provide a scientific basis for quarantine policies, promote the analysis of health damage caused by COVID-19 and the development of active prevention and treatment methods, and activate COVID-19 big data by making them available to private researchers (April 2022) [4].

These big data, which were created by combining the COVID-19 confirmed cases and vaccination data of KDCA with the national health information of NHIS, have been named K-COV-N (KDCA Covid-19 NHIS cohort).

To request COVID-19 big data, users need to apply to the National Insurance Health Sharing Service (NIHSS) website of NHIS; then, KDCA reviews the appropriateness of the requested data to use COVID-19 database (DB). Only the data requested and approved by KDCA shall be provided to the applicant through the NHIS Data Provision Review Committee.

COVID-19 big data are provided in the form of a DB customized for the applicant’s research purpose from NHIS, which undergoes a de-identification process to remove information that can identify individuals.

2. Research Outcomes Utilizing Coronavirus Disease 2019 Big Data and Plans for Its Use

As of October 2, 2024, 211 applications have been approved since the release of COVID-19 big data in April 2022, and 30 papers have been published in international journals, indicating active and diverse research outcomes using COVID-19 big data.

Such data are expected to provide a foundation for preemptive protection measures for susceptible and high-risk groups, for utilization in vaccination promotion and post-vaccination monitoring measures, and for follow-up studies of people with chronic COVID-19 syndrome (long COVID). The cumulative research outcomes from COVID-19 big data are shown below by category (Table 1).

Table 1. Major research results of K-COV-N utilization.

Classification	Number (duplication)a)	Major research results
COVID-19 infection risk factors	16	Increase in neonatal intensive care unit admissions due to maternal COVID-19 infection confirmed Confirmation of high-risk groups for COVID-19 infection or severe symptoms (patients with mental illness, patients with abnormal blood sugar control, organ transplant patients, patients with autoimmune diseases, obesity, asthma, patients with chronic childhood diseases, etc.) COVID-19 Omicron pandemic easier transmission among children confirmed
Vaccination effect	18	People who have been vaccinated against COVID-19 have a reduced risk of developing myocardial infarction, cerebral infarction, cardiovascular disease, and facial paralysis after COVID-19 infection The following risks are not increased by vaccination: autoimmune diseases, retinal artery and vein occlusion, early pregnancy loss, chronic diseases, and adverse effects in adolescents If you have a history of uveitis, ophthalmological monitoring is required after vaccination Risk of most AI-CTDs is not increased after COVID-19 vaccination (mRNA)
Long COVID	4	Adults infected with COVID-19 have a higher risk of developing allergic diseases compared to those who were not infected Patients with COVID-19 infection are at higher risk of developing short- and long-term neuropsychiatric sequelae compared to the general population and patients with acute respiratory infections
Using antibiotics	1	The rate of antibiotic use is higher in severe COVID-19 patients than in influenza patients

K-COV-N=KDCA Covid-19 NHIS cohort; COVID-19=coronavirus disease 2019; AI-CTDs=autoimmune connective tissue diseases; long COVID=chronic COVID-19 syndrome. ^a)If there are more than two main research results of the paper, write the number of episodes in duplicate.

Research on risk factors for COVID-19 infection has identified increased admissions to the neonatal intensive care unit due to maternal COVID-19 infection and also identified groups at increased risk of COVID-19 infection or severe disease.

Studies on the effects of COVID-19 vaccination have shown a reduced risk of myocardial infarction, cerebral infarction, cardio-cerebrovascular disease, and facial paralysis after COVID-19 infection in those who received vaccination. Conversely, vaccination does not increase the risk of autoimmune disease, retinal artery and vein occlusion, or adverse events in adolescents with chronic diseases.

COVID-19 symptoms/signs commonly last up to 4 weeks after diagnosis (i.e., acute COVID-19), while chronic COVID-19 syndrome, also known as long COVID, is defined as one or more symptoms/signs that occurred during or after the acute phase, are not explained by other conditions, and persist beyond 4 weeks to 3 months after COVID-19 diagnosis [5]. Relevant studies have found an increased risk of allergic diseases in adults with COVID-19 compared to those without, and an increased risk of short- and long-term neuropsychiatric sequelae in those infected with COVID-19 compared to the general population and patients with acute respiratory infections. Regarding COVID-19 therapeutics, higher rates of antibiotic use were found in severely ill COVID-19 patients compared to those infected with influenza.

1) Regarding risk factors for coronavirus disease 2019 infection

The paper “Identifying susceptibility of children and adolescents to the Omicron variant (B.1.1.529)” [6] from the research team of Professor June Young Chun at the National Cancer Center reported that the Omicron variant tended to spread more easily among children compared to the previous Omicron variants.

This study identified a susceptible age group for the Omicron variant virus and showed that it can be used as a basis for planning for future outbreaks.

The paper “Protective effect of vaccination on the risk of cardiovascular disease after SARS-CoV-2 infection” by the research team of Professor Sang Min Park from Seoul National University [7] reported a significant increase in the incidence of cardiovascular diseases within 1 month of confirmed COVID-19 infection. Additionally, the study found a 38% reduction in cardiovascular disease among second-dose vaccine recipients and a 56% reduction among third or more doses compared to the unvaccinated. These findings suggested that vaccination may reduce the risk of cardiovascular diseases as a sequela or complication.

Additionally, the paper “COVID-19 vaccination, incidence, and mortality rates among individuals with mental disorders in South Korea: A nationwide retrospective study” by the research team of Professor Hejin Lee from Seoul National University Bundang Hospital [8] showed that people with mental disorders had up to four times higher mortality rates from COVID-19 compared to the general population. These findings indicate that the risk of infection may be higher in certain populations during a pandemic such as COVID-19.

2) Regarding the effects of vaccinations

The paper “Association between vaccination and acute myocardial infarction and ischemic stroke after COVID-19 infection” [9] by the research team of Professor Jaehun Jung, Gachon University, showed that the risk of myocardial infarction and cerebral infarction after COVID-19 infection decreased by more than half in those who were vaccinated against COVID-19. This suggests the need to provide COVID-19 vaccination for groups with risk factors for cardiovascular diseases.

Two studies, “Risk of autoimmune skin and connective tissue disorders after mRNA-based COVID-19 vaccination” [10] and “Long-term risk of autoimmune diseases after mRNA-based SARS-CoV2 vaccination in a Korean, nationwide, population-based cohort study” [11] by the research team of Professor Solam Lee, Wonju Severance Christian Hospital, Yonsei University, concluded that COVID-19 vaccination is not associated with an increased risk of most autoimmune and connective tissue diseases. As such, the mRNA-based COVID-19 vaccine does not increase the risk of autoimmune and connective tissue diseases after vaccination and can thus be used to assess the risk of vaccination.

The paper “Retinal artery and vein occlusion risks after coronavirus disease 2019 or coronavirus disease 2019 vaccination” by the research team of Professor Yong Joon Kim from Yonsei University [12] showed no increase in the risk of retinal artery occlusion/vein occlusion within 60 days of COVID-19 infection or vaccination.

The research team led by Professor Seung-Ah Choe, Korea University, published a study entitled “Effectiveness and safety of COVID-19 vaccination during preconceptional and preclinical pregnancy period: A national population study” [13], in which they analyzed COVID-19 vaccination and the risk of miscarriage during preconception and early pregnancy and found a significant difference in the risk of early miscarriage between the vaccinated and unvaccinated groups.

These results provide evidence of the efficacy and safety of COVID-19 vaccines in early pregnancy and can be used as a basis for COVID-19 safety in pregnancy.

3) Regarding chronic coronavirus disease 2019 syndrome

For a study on long COVID, Professor Dong Keon Yon and colleagues at Kyung Hee University [14] reported a study titled “Incident allergic diseases in post-COVID-19 condition: multinational cohort studies from South Korea, Japan and the UK.” The paper focused on COVID-19 infection and the associated risk of developing allergic diseases and showed that adults infected with COVID-19 had a 20% higher risk of developing allergic diseases compared to those who were not infected; the same trend was found in Japanese (165%) and UK (14%) cohorts. This was the first study to identify an association between long COVID and the risk of developing allergic diseases. The study provided information on the risk of developing allergic diseases in COVID-19 patients using health clinical data. It also demonstrated that long-COVID research in ROK is not only focused on the severity of the disease but also on research specifically needed for Korean people.

4) Regarding antibiotic use during coronavirus disease 2019

Last, the study “Antibiotic prescription in patients with coronavirus disease 2019: Analysis of national health insurance system data in the Republic of Korea” the research team of Professor Hong Bin Kim, Seoul National University Bundang Hospital addressed antibiotic use during COVID-19 [15].

The researchers compared antibiotic prescription data for inpatients with COVID-19 and influenza and found that antibiotic use was higher in the influenza group (57%) than in the overall COVID-19 group (21%), while antibiotic use was higher in the severe COVID-19 group (67%) than in the influenza group (21%).

These results suggested the need for appropriate antibiotic use during the pandemic, considering disease severity and risk of bacterial co-infection.

Conclusion

To expand the collaboration with NHIS from a COVID-19 big data-focused collaboration to a collaboration for infectious disease research, KDCA seeks to link health information data and expand infectious diseases to be analyzed.

In this context, KDCA plans to expand the linkage of infectious diseases other than COVID-19 to promote infectious disease-related research and contribute to improving national health. To promote the utilization of COVID-19 big data, KDCA held the “Workshop for Establishing a Practice Network for Utilizing COVID-19 Big Data” (May 3, 2023) targeting those in charge of using COVID-19 big data in the public and private sectors, where they shared examples of using COVID-19 big data and analysis techniques and established a public-private data analysis network to activate exchanges among those in charge. Additionally, KDCA held the “COVID-19 Big Data Utilization Practice Network Workshop” (October 26, 2023) to strengthen the capabilities of big-data analysis and utilization, providing training on how to design and apply COVID-19 big-data research methodology. The COVID-19 big-data symposium will continue to be held to share findings from COVID-19 big-data research and discuss future research plans annually.

The National Cancer Center, another partner institution, runs the K-CURE Cancer Public Library Project. The library holds big data on cancer patients in ROK was designed to pseudonymize data on the registration, screening, healthcare utilization, and death of cancer patients. It is being held by public institutions so that it can be used for research. KDCA has expanded its cooperation with health information retention institutions, such as linking COVID-19 data with the K-CURE Cancer Public Library of the National Cancer Center and opening it to the public (July 2024), and it continues to promote private research by expanding cooperation with the Health Insurance Review and Assessment Service, another institution that holds health-related big data [16]. Additionally, it should fulfill the public’s right to know and promote infectious disease research in the private sector in areas that need to be expanded through big data research, such as population-based vaccine effectiveness research, antibiotic resistance-related research, and treatment status of chronic infectious diseases that require long-term follow-up.