OBJECTIVES: We aimed to evaluate the severity of suspected severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) reinfection according to variants of concern in Gyeongsangbuk-do and Daegu, Korea. METHODS: The database of coronavirus disease 2019 (COVID-19) cases reported from epidemiological investigations through the integrated system operated by the Korea Disease Control and Prevention Agency, from January 20, 2020 to May 7, 2022 was combined with data from the Health Insurance Review and Assessment Service system. The severity odds ratio (SOR) in secondary infection episodes compared with primary infection was estimated using a generalized linear model with a binomial distribution. RESULTS: In all patients, the SOR of SARS-CoV-2 reinfection was 0.89 (95% confidence interval [CI], 0.82 to 0.95), and the severity was lower than in the first infection. Patients who had been vaccinated within 91 days showed a more attenuated SOR (0.85; 95% CI, 0.74 to 0.98). However, despite vaccination, in patients with both primary and secondary infections caused by the Omicron variant, the severity was reduced to a lesser extent than in patients primarily infected with other variants. CONCLUSIONS We could make efforts to relieve the severity of COVID-19 in vulnerable populations, in which death is more likely, by recommending booster vaccinations in case of a resurgence.

Health risk appraisal (HRA) is a systematic approach for collecting information regarding individual risk factors, predicting the probability of disease occurrence and death, and linking patients with interventions to promote health and prevent disease. Because the risk factors of cardiovascular disease are well established, several cardiovascular disease risk prediction models have been developed over multiple decades. The health risk appraisal prediction model of the Korean national health screening program will be revised and updated using the latest well-validated studies to reflect the current characteristics of the Korean population and to improve the effectiveness of education and behavioral modifications. It is necessary to provide various tools such as a web page and smartphone application to increase the utility of this program in the future.
Behavior Control ; Cardiovascular Diseases* ; Education ; Health Status Indicators* ; Humans ; Mass Screening* ; Risk Factors ; Smartphone

Objectives: This study aimed to present data on reported adverse events following coronavirus disease 2019 (COVID-19) vaccination in Republic of Korea from February 26 to October 31, 2021, and to determine whether any significant patterns emerged from an analysis of the characteristics of suspected adverse event cases for each type of vaccine. Methods: Adverse events following COVID-19 vaccination reported by medical doctors and forensic pathologists were analyzed. Cases of suspected anaphylaxis were classified using the Brighton Collaboration definition. Results: By October 31, 2021, a total of 353,535 (0.45%) adverse events were reported after 78,416,802 COVID-19 vaccine doses. Of the adverse events, 96.4% were non-serious and 3.6% were serious. The most frequently reported adverse events were headache, myalgia, and dizziness. Of the 835 reported deaths after COVID-19 vaccination, 2 vaccine-related deaths were confirmed. Suspected anaphylaxis was confirmed in 454 cases using the Brighton Collaboration definition. Conclusion The commonly reported symptoms were similar to those described in clinical trials. Most reported adverse events were non-serious, and the reporting rate of adverse events following COVID-19 vaccination was higher in women than in men (581 vs. 315 per 100,000 vaccinations). Confirmed anaphylaxis was reported in 5.8 cases per 1,000,000 vaccinations.

Objectives: On February 26, 2021, coronavirus disease 2019 (COVID-19) vaccination was started for high-priority groups based on the recommendation of the Advisory Committee on Immunization Practices with 2 available COVID-19 vaccines (AstraZeneca and Pfizer-BioNTech) in Korea. This report provides a summary of adverse events following COVID-19 vaccination as of April 30, 2021. Methods: Adverse events following immunization are notifiable by medical doctors to the Korea Immunization Management System (KIMS) under the national surveillance system. We analyzed all adverse events reports following COVID-19 vaccination to the KIMS from February 26 to April 30, 2021. Results: In total, 16,196 adverse events following 3,586,814 administered doses of COVID-19 vaccines were reported in approximately 2 months (February 26 to April 30, 2021). Of these, 15,658 (96.7%) were non-serious adverse events, and 538 (3.3%) were serious adverse events, including 73 (0.5%) deaths. The majority of adverse events (n=13,063, 80.7%) were observed in women, and the most frequently reported adverse events were myalgia (52.2%), fever (44.9%), and headache (34.9%). Of the 73 deaths following the COVID-19 vaccination, none were related to the vaccines. Conclusion By April 30, 3.6 million doses of the COVID 19 vaccine had been given in Korea, and the overwhelming majority of reports were for non-serious events. The Korea Disease Control and Prevention Agency continues to monitor the safety of COVID-19 vaccination.

Objectives: On February 26, 2021, coronavirus disease 2019 (COVID-19) vaccination was started for high-priority groups based on the recommendation of the Advisory Committee on Immunization Practices with 2 available COVID-19 vaccines (AstraZeneca and Pfizer-BioNTech) in Korea. This report provides a summary of adverse events following COVID-19 vaccination as of April 30, 2021. Methods: Adverse events following immunization are notifiable by medical doctors to the Korea Immunization Management System (KIMS) under the national surveillance system. We analyzed all adverse events reports following COVID-19 vaccination to the KIMS from February 26 to April 30, 2021. Results: In total, 16,196 adverse events following 3,586,814 administered doses of COVID-19 vaccines were reported in approximately 2 months (February 26 to April 30, 2021). Of these, 15,658 (96.7%) were non-serious adverse events, and 538 (3.3%) were serious adverse events, including 73 (0.5%) deaths. The majority of adverse events (n=13,063, 80.7%) were observed in women, and the most frequently reported adverse events were myalgia (52.2%), fever (44.9%), and headache (34.9%). Of the 73 deaths following the COVID-19 vaccination, none were related to the vaccines. Conclusion By April 30, 3.6 million doses of the COVID 19 vaccine had been given in Korea, and the overwhelming majority of reports were for non-serious events. The Korea Disease Control and Prevention Agency continues to monitor the safety of COVID-19 vaccination.

Objectives: This study aimed to disseminate information on coronavirus disease 2019 (COVID-19) vaccine safety among adolescents aged 12 to 17 years in the Republic of Korea. Methods: Two databases were used to assess COVID-19 vaccine safety in adolescents aged 12 to 17 years who completed the primary Pfizer-BioNTech vaccination series. Adverse events reported to the web-based COVID-19 vaccination management system (CVMS) and collected in the text message-based system were analyzed. Results: From March 5, 2021 to February 13, 2022, 12,216 adverse events among 12- to 17-year-olds were reported to the CVMS, of which 97.1% were non-serious adverse events and 2.9% were serious adverse events, including 85 suspected cases of anaphylaxis, 74 suspected cases of myocarditis and/or pericarditis, and 2 deaths. From December 13, 2021 to January 26, 2022, 10,389 adolescents responded to a text message survey, and local/systemic adverse events were more common after dose 2 than after dose 1. The most commonly reported events following either vaccine dose were pain at the injection site, headache, fatigue/tiredness, and myalgia. Conclusion The overall results are consistent with previous findings; the great majority of adverse events were non-serious, and serious adverse events were rare among adolescents aged 12 to 17 years following Pfizer-BioNTech COVID-19 vaccination.

OBJECTIVES: In Korea, a national coronavirus disease 2019 (COVID-19) vaccination program was implemented, including 4 vaccines against COVID-19. A text messaging-based survey, in addition to a passive adverse event reporting system, was launched to quickly report unusual symptoms post-vaccination. This study compared the frequency of adverse events after COVID-19 vaccination based on the vaccine type and the type of 2-dose regimen (homologous or heterologous). METHODS: Self-reported adverse events were collected through a text-message survey for 7 days after each vaccination. This study included 50,950 vaccine recipients who responded to the survey at least once. Informed consent to receive surveys via text was obtained from the vaccine recipients on the date of first vaccination. RESULTS: The recipients of mRNA vaccines reported local and systemic reactions 1.6 times to 2.8 times more frequently after dose 2 than after dose 1 (p<0.001), whereas ChAdOx1-S recipients reported significantly fewer local and systemic reactions after dose 2 than after dose 1 (p<0.001). Local and systemic reactions were approximately 2 times and 4 times more frequent for heterologous vaccination than for BNT162b2/BNT162b2 and ChAdOx1-S/ChAdOx1-S regimens, respectively. Young individuals, female, and those receiving heterologous vaccine regimens including ChAdOx1-S/BNT162b2 vaccines reported more adverse events than older participants, male, and those with homologous vaccine regimens. CONCLUSIONS Although a heterologous regimen, youth, and female sex were associated with a higher risk of adverse reactions after COVID-19 vaccination, no critical issues were noted. Active consideration of heterologous schedules based on the evidence of efficacy and safety appears desirable.