Coronavirus Disease 2019 In Korea Research Articles

Worsening of health disparities across COVID-19 pandemic stages in Korea.

With the end of the coronavirus disease 2019 (COVID-19) pandemic, the health outcomes of this disease in Korea must be examined. We aimed to investigate health outcomes and disparities linked to socioeconomic status during the COVID-19 pandemic in Korea and to identify risk factors for hospitalization and mortality. This nationwide retrospective study incorporated an analysis of individuals with and without COVID-19 in Korea between January 1, 2020, and December 31, 2022. The study period was divided into 4 stages. Prevalence, hospitalization, mortality, and case-fatality rates were calculated per 100,000 population. Multivariate logistic regression was performed to identify risk factors for COVID-19 hospitalization and mortality. Overall, the incidence rate was 40,601 per 100,000 population, the mortality rate was 105 per 100,000 population, and the case-fatality rate was 259 per 100,000 cases. A total of 12,577,367 new cases (24.5%) were recorded in stage 3 and 8,979,635 cases (17.5%) in stage 4. Medical Aid recipients displayed the lowest 3-year cumulative incidence rate (32,737 per 100,000) but the highest hospitalization (5,663 cases per 100,000), mortality (498 per 100,000), and case-fatality (1521 per 100,000) rates. Male sex, older age, lower economic status, non-metropolitan area of residence, high Charlson comorbidity index, and disability were associated with higher risk of hospitalization and death. Vaccination was found to reduce mortality risk. As the pandemic progressed, surges were observed in incidence, hospitalization, and mortality, exacerbating disparities associated with economic status and disability. Nevertheless, Korea has maintained a low case-fatality rate across all economic groups.

Effectiveness of Bivalent mRNA Booster Vaccine Against COVID-19 in Korea.

Bivalent booster mRNA vaccines containing the omicron-variant strains have been introduced worldwide in the autumn of 2022. Nevertheless, the omicron subvariants evoked another large coronavirus disease 2019 (COVID-19) pandemic wave in late 2022 and early 2023. A retrospective, test-negative, case-control study was conducted to estimate the vaccine effectiveness (VE) of bivalent COVID-19 vaccines in 8 university hospitals between January and February 2023. The case and control groups were divided based on nasopharyngeal COVID-19 real-time polymerase chain reaction results and matched based on age, sex, hospital, and date (week) of the test performed. The VE of the BA.1- or BA.4/BA.5-based mRNA vaccines were estimated. VE was calculated using the 1-adjusted odds ratio from multivariable logistic regression. In total, 949 patients and 947 controls were enrolled in this study. VE for the BA.4/BA.5-based bivalent mRNA vaccine was 43% (95% confidence interval [CI], 17, 61%). In subgroup analysis based on age and underlying medical conditions, BA.4/BA.5-based bivalent mRNA vaccine was effective against old adults aged ≥ 65-years (VE, 55%; 95% CI, 23, 73%) and individuals with comorbidities (VE, 54%; 95% CI, 23, 73%). In comparison, the BA.1-based bivalent mRNA vaccine did not demonstrate statistically significant effectiveness (VE, 25%; 95% CI, -8, 49%). The BA.4/BA.5-based bivalent mRNA booster vaccine provided significant protection against COVID-19 in the Korean adults, especially in the older adults aged ≥ 65 years and in individuals with underlying medical conditions.

Comparison of COVID-19 vaccine policies and their effectiveness in Korea, Japan, and Singapore

BackgroundThis study aimed to analyze coronavirus disease 2019 (COVID-19)vaccine policies and effectiveness in Korea, Japan, and Singapore, thereby providing empirical experience for vaccination and response to similar public health emergencies.MethodsThe study systematically summarized the COVID-19 vaccine policies in Korea, Japan, and Singapore through public information from the Our World in Data website and the official websites of the Ministries of Health in these three countries.Total vaccinations, COVID-19 vaccination rates, rates of fully vaccinated, rates of boostervaccinated, and total confifirmed cases were selected for cross-sectional comparison of COVID-19 vaccination in these three countries. Combining the basic characteristics of these three countries, daily cases per million, daily deaths per million, and the effective reproduction rate were calculated to measure the effectiveness of COVID-19 vaccine policies implementation in each of these three countriesResultsThe countermeasures against the COVID-19 in Korea, Japan, and Singapore, although seemingly different on the surface, have all taken an aggressive approach. There are large similarities in the timing of the start of COVID-19 vaccination, the type of vaccine, how vaccine appointments are made, and whether vaccination are free, and all had high vaccination rates. A systematic comparison of the anti-epidemic practices in the three East Asian countries revealed that all three countries experienced more than one outbreak spike due to the spread of new mutant strains after the start of mass vaccination with COVID-19 vaccination, but that vaccination played a positive role in reducing the number of deaths and stabilizing the effective reproduction rate.ConclusionsThis study comparatively analyzed the COVID-19 vaccine policies and their effects in South Korea, Japan, and Singapore, and found that there is a common set of logical combinations behind the seemingly different strategies of these three countries. Therefore, in the process of combating COVID-19, countries can learn from the successful experience of combating the epidemic and continue to strengthen the implementation of vaccination programs, as well as adjusting public perceptions to reduce the level of vaccine hesitancy, enhance the motivation for vaccination, and improve the coverage of COVID-19 vaccine based on different cultural factors, which remains the direction for future development.

Human resources and medical supplies consumption during the COVID-19 pandemic: a single-center study

Background: In the face of the unexpected coronavirus disease 2019 (COVID-19) pandemic, every country has struggled with insufficient human resources and medical supplies. This study aims to provide the statistical information necessary for discussing how to model stockpiles of medical resources.Methods: This study was conducted at the Hallym University Kangnam Sacred Heart Hospital, in South Korea. The study duration was 2 weeks, centered on March 16, 2022, when the number of daily confirmed patients with COVID-19 in Korea peaked. The number of human resources was obtained by counting the number of healthcare workers using CCTV. Drug prescriptions and medical device usage were obtained from electronic medical records.Results: In total, 117 inpatients and 26,485 outpatients were managed at this hospital during the 2-week study period. Daily visits were highest among nurses in all units, followed by doctors and radiology technicians. The mean daily consumption of personal protective equipment (PPE) per bed was 4.3 sets in the intensive care unit (ICU), 1.8 in the semi-ICU, and 1.4 in the ward. Despite the four-fold difference in the number of patients, there was no statistically significant difference between the two wards in the number of daily visits. Drug prescription rates were higher among inpatients than at-home patients.Conclusions: The higher the COVID-19 severity, the higher the consumption of PPE per patient. Among healthcare workers, nurses had the highest number of inpatient treatment visits for COVID-19. To efficiently utilize, PPE, structures containing more isolation beds in a single negative pressure isolation system would be preferred.

Effective vaccination strategies to control COVID-19 in Korea: a modeling study.

In Korea, as immunity levels of the coronavirus disease 2019 (COVID-19) in the population acquired through previous infections and vaccinations have decreased, booster vaccinations have emerged as a necessary measure to control new outbreaks. The objective of this study was to identify the most suitable vaccination strategy for controlling the surge in COVID-19 cases. A mathematical model was developed to concurrently evaluate the immunity levels induced by vaccines and infections. This model was then employed to investigate the potential for future resurgence and the possibility of control through the use of vaccines and antivirals. As of May 11, 2023, if the current epidemic trend persists without further vaccination efforts, a peak in resurgence is anticipated to occur around mid-October of the same year. Under the most favorable circumstances, the peak number of severely hospitalized patients could be reduced by 43% (n=480) compared to the scenario without vaccine intervention (n=849). Depending on outbreak trends and vaccination strategies, the best timing for vaccination in terms of minimizing this peak varies from May 2023 to August 2023. Our findings suggest that if the epidemic persist, the best timing for administering vaccinations would need to be earlier than currently outlined in the Korean plan. It is imperative to continue monitoring outbreak trends, as this is key to determining the best vaccination timing in order to manage potential future surges.

Beyond Acute COVID-19: Investigating the Incidence of Subacute Thyroiditis in Long COVID-19 in Korea.

The correlation between acute coronavirus disease 2019 (COVID-19) and subacute thyroiditis (SAT) has not been clearly investigated in "long COVID" patients. We aimed to investigate the incidence of SAT during convalescence and after the acute phase of COVID-19, comparing with that of the general population. Data from a total of 422,779 COVID-19 patients and a control group of 2,113,895 individuals were analyzed. The index date was defined as the date 3 months after confirmation of COVID-19. The incidence rate (IR) of SAT and hazard ratios (HRs) were calculated per 100,000 persons. Subgroup analysis included analysis of HRs 90-179 and 180 days post-COVID-19 diagnosis; and additional analysis was conducted according to hospitalization status, sex, and age group. The IR of SAT was 17.28 per 100,000 persons (95% confidence interval [CI], 12.56 to 23.20) in the COVID-19 group and 8.63 (95% CI, 6.37 to 11.45) in the control group. The HR of COVID-19 patients was 1.76 (95% CI, 1.01 to 3.06; P=0.045). The HR of SAT was 1.39 (95% CI, 0.82 to 2.34; P=0.220) up to 6 months after the index date and 2.30 (95% CI, 1.60 to 3.30; P<0.001) beyond 6 months. The HR for SAT among COVID-19 patients was 2.00 (95% CI, 1.41 to 2.83) in hospitalized patients and 1.76 (95% CI, 1.01 to 3.06) in non-hospitalized patients compared to the control group. The IR of SAT was 27.09 (95% CI, 20.04 to 35.82) for females and 6.47 (95% CI, 3.34 to 11.30) for males. In the 19 to 64 age group, the IR of SAT was 18.19 (95% CI, 13.70 to 23.67), while the IR was 9.18 (95% CI, 7.72 to 10.84) in the 65 to 69 age group. SAT could be a potential long-term complication of COVID-19. Long-term surveillance for thyroid dysfunction is needed especially in hospitalized, female and young-aged subjects.

Epidemiologic and Clinical Features of Campylobacter Enteritis Before and During COVID-19 in Korea.

With the increase in meals at home due to coronavirus disease 2019 (COVID-19), the pattern and incidence of enteritis seemed to change. Some types of enteritis, such as Campylobacter enteritis, appear to have increased. Our study aimed to evaluate the change in the trend of enteritis, especially Campylobacter enteritis, before COVID-19 (2016-2019) and at the present time during COVID-19 in South Korea. We analyzed data from the Health Insurance Review and Assessment Service. From 2016 to 2020, the International Classification of Diseases codes related to enteritis were examined to distinguish bacterial and viral enteritis and the trends of each were analyzed. The aspects of enteritis, before and after the COVID-19 outbreak, were compared. Both bacterial and viral enteritis declined in all age groups from 2016 to 2020 (P < 0.001). In 2020, the reduction rate of viral enteritis was higher than that of bacterial enteritis. However, unlike other causes of enteritis, even after COVID-19, Campylobacter enteritis increased in all age groups. An increase of Campylobacter enteritis in 2020 was particularly noticeable in children and adolescents. The prevalence of viral and bacterial enteritis was higher in urban areas than in rural areas (P < 0.001). Campylobacter enteritis was more common in the rural areas (P < 0.001). Although the prevalence of bacterial and viral enteritis have decreased in COVID-19, Campylobacter enteritis has increased in all age groups and in rural areas compared to urban areas. Recognizing that the trend of Campylobacter enteritis before and during COVID-19 is helpful for future public health measures and interventions.

Risk Factors for Sudden Death Within 2 Days After Diagnosis of COVID-19 in Korea.

We aimed to analyze the risk factors for sudden death after diagnosis of coronavirus disease 2019 (COVID-19) in South Korea and to provide evidence for informing prevention and control interventions for patients at risk of sudden death. We included 30,302 COVID-19 related deaths registered in the patient management information system (Central Disease Control Headquarters) between January 1, 2021, and December 15, 2022. We collected their epidemiological data recorded by the reporting city, province, or country. We performed multivariate logistic regression analysis to identify risk factors for sudden death after diagnosis of COVID-19. Among the 30,302 deaths, there were 7,258 (24.0%) and 23,044 (76.0%) sudden and non-sudden deaths, respectively. Sudden death means a person who died within 2 days of diagnosis and who did not receive inpatient treatment. Underlying condition, vaccination status, and place of death were significantly associated with the survival period in all age groups. Moreover, region, sex, and prescription were significantly associated with the survival period only in certain age groups. However, reinfection was not significantly associated with the survival period in any age group. To our knowledge, this is the first study on the risk factors for sudden death after a diagnosis of COVID-19, which included age, underlying condition, vaccination status, and place of death. Additionally, individuals aged < 60 years without an underlying condition were at high risk for sudden death. However, this group has relatively low interest in health, as can be seen from the high non-vaccination rate (16.1% of the general population vs. 61.6% of the corresponding group). Therefore, there is a possibility for the presence of an uncontrolled underlying disease in this population. In addition, many sudden deaths occurred due to delayed hospital visits to continue economic activities even after the onset of COVID-19 symptoms (7 days overall vs. 10 days average for the group). In conclusion, 'continued interest in health' is a key factor in avoiding sudden death in the economically active group (under 60 years of age).

Mask-Wearing Behaviors after Two Years of Wearing Masks Due to COVID-19 in Korea: A Cross-Sectional Study.

In Korea, wearing masks in public places has become the norm during the prolonged coronavirus disease 2019 (COVID-19) pandemic. This cross-sectional study investigated the mask-wearing behavior of Koreans (n = 433) via online mode living in Seoul and Gwangju after wearing a mask in public spaces for two years due to COVID-19. The respondents selected their face masks based on season, gender, age, occupation, mask-wearing hours, mask filter performance, mask shape, and mask color. The general discomfort caused by wearing a mask was divided into physical and speech discomfort, and it was not correlated with anxiety when not wearing a face mask. Speech discomfort caused by wearing a mask was correlated with general discomfort, clear speech, vocal pain, anxiety, and only-indoor mask-off plans. Anxiety when not wearing a mask appeared to affect both indoor and outdoor mask-off plans. The more uncomfortable and less anxious respondents were when not wearing a mask, the sooner they wanted to discontinue wearing masks indoors and outdoors. It is expected that the use of masks will continue in the future and that there may be differences in the place and time of use of masks in Korea and around the world due to new infectious diseases and fine dust. Facial masks can be worn more comfortably and conveniently if the discomfort and anxiety of wearing a mask are improved by considering various behaviors when wearing a mask in the future.

Effect of Anxiety and Calling on Professional Quality of Life in COVID-19 Dedicated Nurses in Korea.

This study was conducted to investigate the anxiety, calling, and professional quality of life (ProQOL) of coronavirus disease 2019 (COVID-19)-dedicated nurses at COVID-19 hospitals and to identify the factors influencing the ProQOL in COVID-19-dedicated nurses. For this descriptive correlational study, data were collected from June to September, 2021, using structural questionnaires completed by 149 nurses working at four general hospitals with inpatient treatment facilities for patients with COVID-19 in Korea. The State–Trait Anxiety Inventory, Multidimensional Calling Measure, and ProQOL 5 were employed for the survey. The data were examined using descriptive analysis, independent t-tests, one-way analysis of variance, Pearson’s correlation coefficients, and multiple regression analysis. The factors influencing compassion satisfaction were state anxiety, trait anxiety, and calling, with an explanatory power of 64%. The factors influencing burnout were trait anxiety and calling, and the explanatory power was 52%. The factors influencing secondary traumatic stress were state anxiety and trait anxiety, and the explanatory power was 23%. Based on the results, lower anxiety and calling influence the ProQOL of COVID-19-dedicated nurses. We propose that programs to raise and maintain ProQOL should be developed and applied.

Stress, and coping strategy of university students during COVID-19 in Korea: The mediating role of ego-resiliency

We aimed to identify the level of stress, ego-resiliency (ER), and coping strategies of university students during the onset of coronavirus disease 2019 (COVID-19) and examine the mediating role of ER in the relationship between stress and coping strategies (e.g., problem-solving, social support seeking, and avoidance). We analyzed responses from 160 university students and found that problem-solving was the most common coping strategy (26.02 ± 4.65), followed by social support-seeking (25.08 ± 5.23), and avoidance (19.21 ± 3.78). ER was negatively associated with stress and showed a mediating effect on the relationship between stress and social support, and stress and problem-solving coping strategies. These findings indicate that ER helps decrease stress caused by the pandemic among university students and should be considered a significant factor for developing adaptive stress coping strategies.

국내 제약·바이오기업들의 제품 R&amp;D/판매 활동이 주가에 미치는 영향: 코로나바이러스감염증-19 치료제 제조기업과 진단키트 제조기업에 대한 사건연구

The market values of many biopharmaceutical firms are known to have increased due to the outbreaks of Coronavirus Disease 2019 (COVID-19). This paper used the “Event Study” methodology to examine press releases’ impact on the stock prices of remedy and diagnosis kits after the pandemic of COVID-19 in Korea. By analyzing 97 events of R&D and marketing activities of the remedy manufacturers and diagnosis kit manufacturers, remedy manufacturers had more significant positive effects than diagnosis kit manufacturers. Furthermore, both manufacturers had strong positive effects on early R&D and sales stages and early periods of event dates. We interpreted these results that biopharmaceutical firms’ development and marketing activities responding to COVID-19 had different impacts on the stock price value according to the level of technological advancement, R&D and sales stages, and the dates of the events. Thus, this paper can give biopharmaceutical firms effective R&D and marketing strategies in response to rapid environmental changes.

Stress, Depression, and Unhealthy Behavior Changes among Patients with Diabetes during COVID-19 in Korea.

The government ordered various restrictions to limit the spread of coronavirus disease 2019 (COVID-19), thus, affecting the mental health status and lifestyle of people with diabetes. This study identifies COVID-19 effects on mental health problems and unhealthy behavioral changes among patients with diabetes. The subjects of this cross-sectional study were adults aged 19 years or older who participated in the 2020 Korean Community Health Survey. Stress, depression, and changes in unhealthy behavior in diabetic patients (N = 26,839) because of COVID-19 were compared with controls (N = 26,834). The association between stress and depression and unhealthy behaviors among patients with diabetes was investigated. During the COVID-19 pandemic, 20.3% and 4.2% of diabetic patients reported higher levels of stress and depression, respectively, than controls. Diabetic patients showed decreased physical activity and sleep time, and increased smoking. Among diabetic patients, stress and depression are associated with unhealthy behavior changes during COVID-19. Measures to promote healthy lifestyles along with stress and depression management strategies must be implemented for the health care of diabetic patients during the pandemic.

The Impact of COVID-19 Protocols on the Continuity of Care for Patients with Hypertension.

The aim of this study was to investigate the impact of the coronavirus disease 2019 (COVID-19) pandemic on the continuity of care (COC) for patients with hypertension. Additionally, the factor of whether participants were treated via telemedicine was also considered. This study used the National Health Insurance and Medical Aid claims data of the Republic of Korea between 2019 and 2020. Multivariable regression analysis was performed to identify the differences in the number of visits and the most frequent provider continuity (MFPC) of hypertensive patients before and after the appearance of COVID-19 in Korea. Additional analysis was performed with data that excluded cases of patients who received telemedicine services. A total of 5,791,812 hypertensive patients were included in this study. The MFPC decreased by 0.0031 points after the appearance of COVID-19, and it showed the same decrease even when telemedicine cases were excluded. The number of outpatient clinic visit days decreased by 0.2930 days after the appearance of COVID-19. Without the telemedicine cases, the number of outpatient clinic visit days decreased by 0.3330 days after the appearance of COVID-19. Accordingly, the COVID-19 protocols did not affect hypertension patients’ COC but impacted the frequency of their outpatient visits. In other words, with or without telemedicine, the utilization of healthcare was not disrupted, but there was a significant difference in the volume of healthcare use depending on the inclusion of telemedicine cases.

Nationwide COVID-19 vaccination coverage and COVID-19 incidence in South Korea, January 2022: a national official report

Objective: To reduce the risk of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, severe coronavirus disease 2019 (COVID-19) illness, and COVID-19 related death, all persons in South Korea should stay up to data with recommended COVID-19 vaccinations. This study investigated the rates and effectiveness of the COVID-19 vaccination in reducing the severity of disease of the entire Korean population. Methods: On January 2022, the official data released by the Korea Disease Control and Prevention Agency was analyzed. The types of COVID-19 vaccines (ChAdOx1-S [AstraZeneca], BNT162b2 [Pfizer-BioNTech], mRNA-1273 [Moderna], and Ad26.COV2.S [Janssen]), the cumulative cases, and the incidences of COVID-19 were estimated. The relative risk reduction of the severe COVID-19 cases was analyzed according to the histories of the COVID-19 vaccination. Results: On January 2022, the cumulative number of patients with COVID-19 cases was 642,207, with the incidence rate of 1,239 per 1,000,000 people. 82.22% [42,219,818/51,349,116] of Koreans have successfully been vaccinated two doses and 36.42% [13,709,545/51,349,116] were vaccinated a booster dose of the COVID-19. The relative risk reduction of severe COVID-19 was 27% (95% confidence interval [95% CI], 24 to 30) for the second dose of the COVID-19 vaccine and 79% (95% CI, 66 to 87) for the booster dose of the COVID-19 vaccine. In the ≥75 years old age group, the relative risk reduction of severe COVID-19 cases was 0.71 (95% CI, 0.69 to 0.73) for the second dose of COVID-19 vaccine and 0.99 (95% CI, 0.99 to 1.00) for the booster dose of COVID-19 vaccine. Conclusion: A maximum of high as 82.22% of Korean has been vaccinated two doses for COVID-19 until by January 2022. The COVID-19 vaccination was effective for reducing the severity of the COVID-19 in Korea. In addition, the preventive effect of COVID-19 vaccine for severe COVID-19 cases was high in old population.

Mental Health of Adolescents and Subjective Economic Deterioration Caused by COVID-19 in Korea

BackgroundThe coronavirus disease 2019 (COVID-19) pandemic greatly impacted the health and economy worldwide. Children and adolescents are less affected by COVID-19 but are more vulnerable to secondary damage, such as mental health. We would like to evaluate the subjective economic changes caused by COVID-19 in Korea and adolescents’ mental health status.MethodsThe data are based on the Korea Youth Risk Behavior Survey, published by the Korea Center for Disease Control and Prevention in South Korea. It is an annual cross-sectional national representative survey of middle and high school students. There were 54,948 subjects, and the survey was conducted from August 3, 2020 to November 13, 2020. We investigated usual stress, loneliness, anxiety, sadness and hopelessness, and suicidal ideation.ResultsWe found that the odds ratio of adolescent mental health increased as the economic deterioration caused by COVID-19 increased. Overall, it was more severe in female students, and the greater the economic change, the worse the anxiety in boys and the worse the sadness and hopelessness in girls.ConclusionWe hope that it will be possible to prevent and intervene early in adolescents, considering not only the risk of infection from COVID-19 but also mental health, especially mental health related to the economic deterioration caused by COVID-19.

Performance Comparison of Five SARS-CoV-2 Antibody Assays for Seroprevalence Studies.

BackgroundSeroprevalence studies of coronavirus disease 2019 (COVID-19) cases, including asymptomatic and past infections, are important to estimate the scale of the disease outbreak and to establish quarantine measures. We evaluated the clinical performance of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibody assays available in Korea for use in seroprevalence studies.MethodsThe sensitivity, specificity, cross-reactivity, and interference of five SARS-CoV-2 antibody assays were evaluated using the following 398 serum samples from confirmed COVID-19 patients, 510 negative control samples from before 2018 (pre-pandemic), 163 serum samples from patients with SARS, Middle East respiratory syndrome (MERS), and other viral infections, and five samples for the interference study.ResultsThe sensitivities of the five assays ranged from 92.2% to 98%, and their specificities, including cross-reactivity and interference, ranged from 97.5% to 100%. The agreement rates were excellent (kappa >0.9). Adjustment of the cutoff values could be considered through ROC curve analysis. The positive predictive values of the individual assays varied from 3.5% to 100% at a 0.1% prevalence but were as high as ≥95% when two assays were combined.ConclusionsThe prevalence of COVID-19 in Korea is considered to be exceptionally low at present; thus, we recommend using a combination of two or more SARS-CoV-2 antibody assays rather than a single assay. These results could help select SARS-CoV-2 antibody assays for COVID-19 seroprevalence studies in Korea.

Chronic Obstructive Pulmonary Disease is Associated with a More Symptomatic Burden and Severe Presentation of COVID-19: A Korean National COVID-19 Cohort Study.

Insufficient data are available on comprehensive evaluation of demographics, symptoms or signs, laboratory findings, and disease course in patients with coronavirus disease 2019 (COVID-19) and chronic obstructive pulmonary disease (COPD). We aimed to evaluate whether COPD patients are more prone to severe COVID-19 compared with those without COPD. We also investigate the clinical characteristics and disease course of COVID-19 in patients with COPD versus those without COPD. Patients were selected from a Korean nationwide cohort of 5,628 patients with confirmed COVID-19 and who had completed treatment or quarantine by April 30, 2020; 3,673 patients aged 40 years or older were included in this study. COPD was diagnosed using patient reports of physician-diagnosed COPD. During the study period, all patients with COVID-19 in Korea were hospitalized following the national health policy. Of the study participants, 38 (1.0%) had COPD. Regarding initial symptoms, COPD patients with COVID-19 showed greater sputum production (50.0% vs. 29.8%, p < 0.01) and dyspnea (36.8% vs. 14.9%, p < 0.01) than those without COPD. In addition, patients with COPD were more likely to receive oxygen therapy or non-invasive ventilation (29.0% vs. 13.7%, p = 0.01) and had a higher mortality (21.1% vs. 6.4%, p < 0.01) than those without COPD. After adjusting for age, sex, body mass index, and comorbidities, COPD patients showed increased risk of severe COVID-19 compared with those without COPD. Our nationwide study showed that COVID-19 patients with COPD have higher symptomatic burden and more severe disease course than those without COPD.

Expert Consensus on COVID-19 Vaccination in Korean Adolescents: A Modified Delphi Survey.

The effectiveness of coronavirus disease 2019 (COVID-19) vaccines had been shown in many studies in adult population, however, the real-world evidence in the childhood population was scarce. We aimed to organize the collective expert’s opinions on adolescent vaccination against COVID-19 in Korea, therefore to guide the vaccination policy in the setting of available evidence. The Delphi panels responded that adolescents were greatly impacted by the quarantine measures, and COVID-19 is an important health problem for adolescents. Panels responded that in general, the benefits of the COVID-19 vaccine overweigh the potential risks in Korean adolescents. Continuing monitoring of available data is needed to provide the best vaccination practices in adolescents guided by the updated evidence.

Analysis of Critical COVID-19 Cases Among Children in Korea.

BackgroundCoronavirus disease 2019 (COVID-19) is generally asymptomatic or mild in otherwise healthy children, however, severe cases may occur. In this study, we report the clinical characteristics of children classified as critical COVID-19 in Korea to provide further insights into risk factors and management in children.MethodsThis study was a retrospective case series of children < 18 years of age classified as critical COVID-19. Cases were identified by the Korea Disease Control and Prevention Agency surveillance system and medical records were reviewed. Critical COVID-19 was defined as cases with severe illness requiring noninvasive (high flow nasal cannula, continuous positive airway pressure, or bilevel positive airway pressure) or invasive mechanical ventilation, extracorporeal membrane oxygenation (ECMO) or continuous renal replacement therapy (CRRT), between January 20, 2020 and October 7, 2021.ResultsAmong 39,146 cases diagnosed with COVID-19 in subjects < 18 years of age, eight cases (0.02%) were identified as critical COVID-19. The median age was 13 years (range 10 month–17 years) and male-to-female ratio was 1:1. Three children had underlying diseases; one child has asthma and major depressive disorder, one child had Lennox-Gastaut syndrome and one child had mental retardation and was newly diagnosed with type 2 diabetes mellitus with the diagnosis of COVID-19. Among the eight children, seven were obese (body mass index range [BMI] median 29.3, range 25.9–38.2, weight-for-length > 97% for infant) and one was overweight (BMI 21.3). All patients had fever, six patients had dyspnea or cough and other accompanied symptoms included sore throat, headache, lethargy and myalgia. Radiologic findings showed pneumonia within 1–8 days after symptom onset. Pneumonia progressed in these children for 2–6 days and was improved within 5–32 days after diagnosis. Among the eight critical cases, remdesivir was administered in six cases. Steroids were provided for all cases. Inotropics were administered in one case. Six cases were treated with noninvasive mechanical ventilator and three required mechanical ventilator. One case required ECMO due to acute respiratory distress syndrome. All cases were admitted to the intensive care unit and admission period ranged from 9–39 days. Among all critical COVID-19 cases < 18 years of age, there were no fatal cases.ConclusionTo develop appropriate policies for children in the COVID-19 pandemic, it is important to monitor and assess the clinical burden in this population.