COVID-19 Vaccination Rates in Patients With Chronic Medical Conditions: A Nationwide Cross-Sectional Study.

As most individuals acquire immunity to severe acute respiratory syndrome coronavirus 2, South Korea declared a return to normalcy a few months ago. However, epidemic waves continue because of endlessly emerging variants and waning immunity. Health authorities are focusing on those at high risk of severe coronavirus disease 2019 to minimize damage to public health and the economy. In this regard, we investigated the vaccination rates in patients with various chronic medical conditions by examining the national health insurance claims data and the national immunization registry. We found that patients with chronic medical conditions, especially those of higher severity, such as malignancy, had vaccination rates approximately 10-20% lower than those of the general population. Public health authorities and healthcare providers should try to vaccinate these patients to avoid preventable morbidity and mortality.

Temporal Correlation Between Kawasaki Disease and Infectious Diseases in South Korea.

Importance: Infections are proposed to be triggering factors for Kawasaki disease (KD), although its etiological factors remain unknown. Recent reports have indicated a 4- to 6-week lag between SARS-CoV-2 infection and multisystem inflammatory syndrome in children with a similar presentation to that of KD. Objective: To investigate the temporal correlation between KD and viral infections, focusing on respiratory viruses. Design, Setting, and Participants: This cohort study was conducted among individuals aged 0 to 19 years diagnosed with KD between January 2010 and September 2020 from the Korean National Health Insurance Service. Data on infectious disease outbreaks from 2016 to 2019 were collected from the Korea Disease Control and Prevention Agency, Korean Influenza and Respiratory Virus Monitoring System, Korea Enteroviruses Surveillance System, and the Enteric Pathogens Active Surveillance Network in South Korea. Data were analyzed from December 2020 to October 2021. Main Outcomes and Measures: National databases for infectious diseases were used for a time-series analysis of the correlation between viral infections and KD. The temporal correlation between infectious disease outbreaks and KD outbreaks was evaluated using the Granger causality test (G-test), which is a useful tool to estimate correlations between 2 time series of diseases based on time lags. Results: Overall, 53 424 individuals with KD were identified, including 22 510 (42.1%) females and 30 914 (57.9%) males and 44 276 individuals (82.9%) younger than 5 years. Intravenous immunoglobulin-resistant KD was identified in 9042 individuals (16.9%), and coronary artery abnormalities were identified in 384 individuals (0.7%). Of 14 infectious diseases included in the analyses, rhinovirus infection outbreaks were identified as significantly correlated at 1 to 3 months before KD outbreaks in South Korea (r = 0.3; 1 month: P < .001; 2 months: P < .001; 3 months: P < .001). Outbreaks of respiratory syncytial virus infection were identified as significantly correlated with KD outbreaks by 2 months (r = 0.5; 2 months: P < .001). Additionally, varicella outbreaks were identified as significantly correlated at 2 and 3 months before KD outbreaks (r = 0.7; 2 months: P < .001; 3 months: P < .001). Conclusions and Relevance: In this cohort study with a time series analysis of children and youth in South Korea with KD, respiratory infections caused by rhinovirus and respiratory syncytial virus and varicella outbreaks were significantly correlated with KD at 1 to 3 months before KD outbreaks.

Unemployment and child maltreatment during the COVID-19 pandemic in the Republic of Korea.

BACKGROUND: Risk factors for child maltreatment have been exacerbated during the COVID-19 pandemic, especially due to economic downfalls leading to parental job losses and poor mental health. OBJECTIVE: This study aimed to examine the association between child maltreatment and unemployment rate in the Republic of Korea. PARTICIPANTS AND SETTING: Nationally representative data at the province level were used. METHODS: The monthly excess number of hotline calls related to child maltreatment during the COVID-19 pandemic was estimated for each province. Fixed effects regressions was used to examine the relationship between the excess number of hotline calls and unemployment rate. RESULTS: The average excess number of hotline calls was significantly negative in the early stage of the pandemic, but became significantly positive afterwards except for some months with averages not statistically different from zero. The regression results showed that an increase of male unemployment rate by 1% was significantly associated with an increase in the excess number of hotline calls by 0.15-0.17 per 10,000 children for most dependent variables for the first year of the COVID-19 pandemic. The statistical significance of female unemployment rate was mixed with the opposite sign of the coefficient to that of male unemployment. Overall unemployment rate was not significant. CONCLUSIONS: This study suggests that disruptions in child welfare services should be avoided to prevent underreporting of or delayed responses to suspected cases. Also, policies need to be designed considering potential pathways from economic downfalls, especially male unemployment, to child maltreatment.

Predicted and Observed Incidence of Thromboembolic Events among Koreans Vaccinated with ChAdOx1 nCoV-19 Vaccine.

We used the nationwide claims database to calculate the incidence of thrombotic events and predict their overall 2-week incidence. From 2006 to 2020, the incidence of deep vein thrombosis (DVT), pulmonary embolism (PE), and disseminated intravascular coagulation (DIC) tended to increase. Unlike intracranial venous thrombosis (ICVT) and intracranial thrombophlebitis (ICTP), which showed no age difference, other venous embolism, and thrombosis (OVET), DIC, DVT, and PE were significantly more common in over 65 years. The overall 2-week incidence of ICVT was 0.21/1,000,000 (95% confidence interval [CI], 0.11-0.32). ICTP, OVET, DIC, DVT and PE were expected to occur in 0.08 (95% CI, 0.02-0.14), 7.66 (95% CI, 6.08-9.23), 5.95 (95% CI, 4.88-7.03), 13.28 (95% CI, 11.92-14.64), 14.09 (95% CI, 12.80-15.37) per 1,000,000, respectively. To date, of 8,548,231 patients vaccinated with ChAdOx1 nCoV-19 in Korea, two had confirmed thrombosis with thrombocytopenia syndrome within 2 weeks. The observed incidence of ICVT after vaccination was 0.23/1,000,000.

Decrease in hospital admissions for respiratory diseases during the COVID-19 pandemic: a nationwide claims study.

Non-pharmaceutical interventions (NPIs) have been widely implemented to mitigate the spread of COVID-19. We assessed the effect of NPIs on hospitalisations for pneumonia, influenza, COPD and asthma. This retrospective, ecological study compared the weekly incidence of hospitalisation for four respiratory conditions before (January 2016-January 2020) and during (February-July 2020) the implementation of NPI against COVID-19. Hospitalisations for all four respiratory conditions decreased substantially during the intervention period. The cumulative incidence of admissions for COPD and asthma was 58% and 48% of the mean incidence during the 4 preceding years, respectively.

Estimating Baseline Incidence of Conditions Potentially Associated with Vaccine Adverse Events: a Call for Surveillance System Using the Korean National Health Insurance Claims Data.

BACKGROUND: Vaccines against coronavirus disease 2019 (COVID-19) are raising concerns about vaccine safety, particularly in the context of large-scale immunization. To address public concerns, we measured the baseline incidence rates of major conditions potentially related to vaccine-related adverse events (VAEs). We aimed to provide a basis for evaluating VAEs and verifying causality. METHODS: Conditions of interest were selected from the US Vaccine Adverse Event Reporting System Table of Reportable Events and a recent report from a European consortium on vaccine surveillance. We used the National Health Insurance Service database in Korea to identify the monthly numbers of cases with these conditions. Data from January 2006 to June 2020 were included. Prediction models were constructed from the observed incidences using an autoregressive integrated moving average. We predicted the incidences of the conditions and their respective 95% confidence intervals (CIs) for January through December 2021. In addition, subgroup analysis for the expected vaccination population was conducted. RESULTS: Mean values (95% CIs) of the predicted monthly incidence of vasovagal syncope, anaphylaxis, brachial neuritis, acute disseminated encephalomyelitis, Bell's palsy, Guillain-Barré syndrome, encephalopathy, optic neuritis, transverse myelitis, immune thrombocytopenic purpura, and systemic lupus erythematosus in 2021 were 23.89 (19.81-27.98), 4.72 (3.83-5.61), 57.62 (51.37-63.88), 0.03 (0.01-0.04), 8.58 (7.90-9.26), 0.26 (0.18-0.34), 2.13 (1.42-2.83), 1.65 (1.17-2.13), 0.19 (0.14-0.25), 0.75 (0.61-0.90), and 3.40 (2.79-4.01) cases per 100,000 respectively. The majority of the conditions showed an increasing trend with seasonal variations in their incidences. CONCLUSION: We measured the incidence of a total of 11 conditions that could potentially be associated with VAEs to predict the monthly incidence in 2021. In Korea, conditions that could potentially be related to VAEs occur on a regular basis, and an increasing trend is observed with seasonality.

Years of Life Lost Attributable to COVID-19 in High-incidence Countries.

BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic is a major public health problem of international concern. It is important to estimate its impact of COVID-19 for health policy decision-making. We estimated the years of life lost (YLLs) due to COVID-19 in high-incidence countries. METHODS: We collected the YLLs due to COVID-19 in 30 high-incidence countries as of April 13, 2020 and followed up as of July 14, 2020. Incidence and mortality were collected using each country's formal reports, articles, and other electronic sources. The life expectancy of Japanese females by age and the UN population data were used to calculate YLLs in total and per 100,000. RESULTS: As of April 22, 2020, there were 1,699,574 YLLs due to COVID-19 in 30 high-incidence countries. On July 14, 2020, this increased to 4,072,325. Both on April 22 and July 14, the total YLLs due to COVID-19 was highest in the USA (April 22, 534,481 YLLs; July 14, 1,199,510 YLLs), and the YLLs per 100,000 population was highest in Belgium (April 22, 868.12 YLLs/100,000; July 14, 1,593.72 YLLs/100,000). YLLs due to COVID-19 were higher among males than among females and higher in those aged ≥ 60 years than in younger individuals. Belgium had the highest proportion of YLLs attributable to COVID-19 as a proportion of the total YLLs and the highest disability-adjusted life years per 100,000 population. CONCLUSION: This study estimated YLLs due to COVID-19 in 30 countries. COVID-19 is a high burden in the USA and Belgium, among males and the elderly. The YLLs are very closely related with the incidence as well as the mortality. This highlights the importance of the early detection of incident case that minimizes severe acute respiratory syndrome coronavirus-2 fatality.

The Burden of Disease due to COVID-19 in Korea Using Disability-Adjusted Life Years.

BACKGROUND: The world is currently experiencing a pandemic of coronavirus disease 2019 (COVID-19). In Korea, as in other countries, the number of confirmed cases and deaths due to COVID-19 have been rising. This study aimed to calculate the burden of disease due to COVID-19 in Korea. METHODS: We used data on confirmed cases and deaths due to COVID-19 between January 20 and April 24, 2020 provided by the Korea Centers for Disease Control and Prevention, the local governments and the public media to determine disability-adjusted life years (DALYs) by sex and age. Morbidity was estimated directly among the confirmed, cured, and fatal cases. Disability weights were adopted from previous similar causes on the severity of COVID-19 for the years of life lived with disability (YLDs). The years of life lost (YLLs) were calculated using the standard life expectancy from the 2018 life tables for each sex and age. RESULTS: The YLDs were higher in females (155.2) than in males (105.1), but the YLLs were higher in males (1,274.3) than in females (996.4). The total disease burden attributable to COVID-19 in Korea during the study period, was estimated to be 2,531.0 DALYs, and 4.930 DALYs per 100,000 population. The YLDs and the YLLs constituted 10.3% and 89.7% of the total DALYs, respectively. The DALYs per 100,000 population were highest in people aged ≥ 80 years, followed by those aged 70-79, 60-69, and 50-59 years, but the incidence was the highest in individuals aged 20-29 years. CONCLUSION: This study provided the estimates of DALYs due to COVID-19 in Korea. Most of the disease burden from COVID-19 was derived from YLL; this indicates that decision-makers should focus and make an effort on reducing fatality for preparing the second wave of COVID-19.