COVID-19 Vaccination in Korea.

Since December 2020, various coronavirus disease 2019 (COVID-19) vaccines have been developed and approved. As of February 2023, mRNA vaccines including bivalent vaccines (Pfizer/BioNTech, Moderna), recombinant protein vaccines (Novavax, SK Bioscience), and viral vector vaccines (AstraZeneca, Janssen) have been approved in Korea. COVID-19 vaccination can effectively reduce hospitalization and deaths due to symptomatic COVID-19, especially severe and critical COVID-19. The primary series vaccination against COVID-19 is recommended for all adults aged ≥18 years in Korea. Booster vaccination with the bivalent mRNA vaccine is available for those ≥12 years who have completed the primary series vaccination, regardless of the type of vaccine previously received, and is recommended for all adults. Booster vaccination can be administered since 90 days after the last dose. Localized and systemic adverse events following COVID-19 vaccination are relatively common and more frequently documented in younger age groups. Rare but potentially serious specialized adverse reactions include anaphylaxis, thrombosis with thrombocytopenia syndrome, myocarditis, and Guillain-Barré syndrome. Previous severe allergic reactions, such as anaphylaxis, to any COVID19 vaccine or vaccine component are considered a contraindication for vaccination. The indications and schedule for COVID-19 vaccination are subject to change based on further research results and the COVID-19 pandemic.

SARS-CoV-2 Variants Associated with Vaccine Breakthrough in the Delaware Valley through Summer 2021.

The severe acute respiratory coronavirus-2 (SARS-CoV-2) is the cause of the global outbreak of COVID-19. Evidence suggests that the virus is evolving to allow efficient spread through the human population, including vaccinated individuals. Here, we report a study of viral variants from surveillance of the Delaware Valley, including the city of Philadelphia, and variants infecting vaccinated subjects. We sequenced and analyzed complete viral genomes from 2621 surveillance samples from March 2020 to September 2021 and compared them to genome sequences from 159 vaccine breakthroughs. In the early spring of 2020, all detected variants were of the B.1 and closely related lineages. A mixture of lineages followed, notably including B.1.243 followed by B.1.1.7 (alpha), with other lineages present at lower levels. Later isolations were dominated by B.1.617.2 (delta) and other delta lineages; delta was the exclusive variant present by the last time sampled. To investigate whether any variants appeared preferentially in vaccine breakthroughs, we devised a model based on Bayesian autoregressive moving average logistic multinomial regression to allow rigorous comparison. This revealed that B.1.617.2 (delta) showed 3-fold enrichment in vaccine breakthrough cases (odds ratio of 3; 95% credible interval 0.89-11). Viral point substitutions could also be associated with vaccine breakthroughs, notably the N501Y substitution found in the alpha, beta and gamma variants (odds ratio 2.04; 95% credible interval of1.25-3.18). This study thus overviews viral evolution and vaccine breakthroughs in the Delaware Valley and introduces a rigorous statistical approach to interrogating enrichment of breakthrough variants against a changing background. IMPORTANCE SARS-CoV-2 vaccination is highly effective at reducing viral infection, hospitalization and death. However, vaccine breakthrough infections have been widely observed, raising the question of whether particular viral variants or viral mutations are associated with breakthrough. Here, we report analysis of 2621 surveillance isolates from people diagnosed with COVID-19 in the Delaware Valley in southeastern Pennsylvania, allowing rigorous comparison to 159 vaccine breakthrough case specimens. Our best estimate is a 3-fold enrichment for some lineages of delta among breakthroughs, and enrichment of a notable spike substitution, N501Y. We introduce statistical methods that should be widely useful for evaluating vaccine breakthroughs and other viral phenotypes.

Effect of self-learning media based on 360° virtual reality for learning periodontal instrument skills.

INTRODUCTION: Of 360° Virtual Reality (VR) is possibly produced and sufficiently effective as a consumer-friendly VR learning medium. Therefore, it is also expected to be useful in the dental practice field, as a self-learning medium for non-face-to-face skill training during the ongoing pandemic (COVID-19). Accordingly, this study was conducted to assess 360° VR self-learning media for a periodontal instrument operation. MATERIALS AND METHODS: We recruited 30 participants who had never experienced instrument training. We offered basic education and initial assessment (IA), then divided them into three groups: 1) PAPER: trained only with paper handouts; 2) 2D: trained with 2D video; 3) VR: trained with 360° VR. Each group performed self-learning and mid-term assessment (MA). Subjects then implemented home self-learning with the same media for one week, which was then followed by a final assessment (FA). RESULT: Analysis of IA-to-FA improvement scores showed that VR and 2D video were significantly higher than the PAPER groups. Meanwhile, analysis of MA-to-FA improvement scores showed that only VR was substantially higher than the PAPER group. Although VR and 2D video groups were not considerably different, VR scores were numerically higher than 2D video in all improvement score analyses. DISCUSSION: Both 2D video and 360° VR training were helpful to participants for an effective self-learning and also had good portability and accessibility as online-based learning methods. 360° VR showed higher learning efficiency than regular 2D video, possibly due to its autonomy, 360° visual information and physical and immersive characteristics, which positively affected self-training. CONCLUSION: Our findings showed the potential of 360° VR learning media and, further, suggest its usefulness as a novel self-learning method in future dental education.

Clinical application of the Panbio™ COVID-19 Ag rapid test device and SSf-COVID19 kit for the detection of SARS-CoV-2 infection.

OBJECTIVE: We evaluated the sensitivity and specificity of the Panbio™ COVID-19 Ag rapid test device using nasal swabs and those of the SSf-COVID19 kit, one of RT-PCR tests, using saliva specimens. These tests were compared with RT-PCR tests using nasopharyngeal swabs for the diagnosis of SARS-CoV-2 infection. The three diagnostic tests were simultaneously conducted for patients aged ≥ 18 years, who were about to be hospitalized or had been admitted for COVID-19 confirmed by RT-PCR in two research hospitals from August 20 to October 29, 2021. Nasal swabs were tested using the Panbio™ COVID-19 Ag rapid test device. More than 1 mL of saliva was self-collected and tested using the SSf-COVID19 kit. RESULTS: In total, 157 patients were investigated; 124 patients who were about to be hospitalized and 33 patients already admitted for COVID-19. The overall sensitivity and specificity of the Panbio™ COVID-19 Ag rapid test device with nasal swabs were 64.7% (95% confidence interval [CI] 47.9-78.5%) and 100.0% (95% CI 97.0-100.0%), respectively. The median time to confirm a positive result was 180 s (interquartile range 60-255 s). The overall sensitivity and specificity of the SSf-COVID19 kit with saliva specimens were 94.1% (95% CI 80.9-98.4%) and 100.0% (95% CI 97.0-100.0%), respectively.

Impact of COVID-19 Pandemic on Thyroid Surgery in a University Hospital in South Korea.

The COVID-19 pandemic has changed healthcare systems around the world. Medical personnel concentrated on infectious disease management and treatments for non-emergency diseases and scheduled surgeries were delayed. We aimed to investigate the change in the severity of thyroid cancer before and after the outbreak of COVID-19 in Korea. We collected three years of data (2019, 2020, and 2021) on patients who received thyroid surgery in a university hospital in South Korea and grouped them as "Before COVID-19", "After COVID-19 1-year" and "After COVID-19 2-years". The total number of annual outpatients declined significantly after the outbreak of COVID-19 in both new (1303, 939, and 1098 patients) and follow-up patients (5584, 4609, and 4739 patients). Clinical characteristics, including age, sex, BMI, preoperative cytology results, surgical extent, and final pathologic diagnosis, were not significantly changed after the outbreak of COVID-19. However, the number of days from the first visit to surgery was significantly increased (38.3 ± 32.2, 58.3 ± 105.2, 47.8 ± 124.7 days, p = 0.027). Papillary thyroid carcinoma (PTC) patients showed increased proportions of extrathyroidal extension, lymphatic invasion, vascular invasion, and cervical lymph node metastasis. Increased tumor size was observed in patients with follicular tumor (3.5 ± 2.2, 4.0 ± 1.9, 4.3 ± 2.3 cm, p = 0.019). After the COVID-19 outbreak, poor prognostic factors for thyroid cancer increased, and an increase in the size of follicular tumors was observed. Due to our study being confined to a single tertiary institution in Incheon city, Korea, nationwide studies that include primary clinics should be required to identify the actual impact of COVID-19 on thyroid disease treatment.

Online Feedback Systems and Debate on Scientific Issues during COVID-19: A Case Study on Sookmyung Women's University.

As the COVID-19 pandemic continues, university education and feedback guidance have inevitably moved to online platforms, becoming a global trend. This study focuses on a case of Sookmyung Women's University in South Korea, which has operated an online discussion clinic for university general education for more than a year as a case study. There are two main research methods. A frequency analysis was conducted to confirm what kind of counseling the students preferred at the discussion clinic based on the answers written in the students' applications. The students whose applications were used for the analysis were divided into 57 teams, and there were two to six members per team. The results were as follows: In the survey results, students wanted help with the preparation process necessary for the discussion and the practical strategies for facilitating discussions. They wanted personalized counseling, demonstrating that discussion education provided in the foundational curriculum is insufficient. Second, the educational model of the discussion clinic and educational examples were examined. The findings confirmed that online discussion education is effective if the system is technically supplemented. Instructors and researchers are prepared to meet students' demands for feedback and individual counseling, even if these are not provided through face-to-face discussions. Additionally, face-to-face guidance can be operated more effectively by taking advantage of online systems. The findings also demonstrate that further research on designing and operating online discussion centers is required. This study is a preceding study on developing online systems and educational guidelines for higher educational institutions to present new insights into smart learning. This paper also includes suggestions for educational and scientific discussions. The online discussion instructional model shown in this paper explores methods of scientific communication through a debate on scientific issues.

Detection of SARS-CoV-2 RNA using RT-LAMP and molecular beacons.

BACKGROUND: Rapid spread of SARS-CoV-2 has led to a global pandemic, resulting in the need for rapid assays to allow diagnosis and prevention of transmission. Reverse transcription-polymerase chain reaction (RT-PCR) provides a gold standard assay for SARS-CoV-2 RNA, but instrument costs are high and supply chains are potentially fragile, motivating interest in additional assay methods. Reverse transcription and loop-mediated isothermal amplification (RT-LAMP) provides an alternative that uses orthogonal and often less expensive reagents without the need for thermocyclers. The presence of SARS-CoV-2 RNA is typically detected using dyes to report bulk amplification of DNA; however, a common artifact is nonspecific DNA amplification, which complicates detection. RESULTS: Here we describe the design and testing of molecular beacons, which allow sequence-specific detection of SARS-CoV-2 genomes with improved discrimination in simple reaction mixtures. To optimize beacons for RT-LAMP, multiple locked nucleic acid monomers were incorporated to elevate melting temperatures. We also show how beacons with different fluorescent labels can allow convenient multiplex detection of several amplicons in "single pot" reactions, including incorporation of a human RNA LAMP-BEAC assay to confirm sample integrity. Comparison of LAMP-BEAC and RT-qPCR on clinical saliva samples showed good concordance between assays. To facilitate implementation, we developed custom polymerases for LAMP-BEAC and inexpensive purification procedures, which also facilitates increasing sensitivity by increasing reaction volumes. CONCLUSIONS: LAMP-BEAC thus provides an affordable and simple SARS-CoV-2 RNA assay suitable for population screening; implementation of the assay has allowed robust screening of thousands of saliva samples per week.

The Lived Experiences of COVID-19 Patients in South Korea: A Qualitative Study.

The purpose of this qualitative study is to provide an in-depth understanding and description of the disease experiences of COVID-19 patients. The participants were 16 patients discharged from hospitals after receiving treatment for COVID-19 in isolation. Data collection was conducted through individual in-depth interviews until data saturation, and the interviews were recorded and transcribed verbatim. Data were analyzed using Colaizzi's phenomenological method. The participants were quarantined after their COVID-19 diagnosis was confirmed, and they experienced desperate and uncertain times during treatment. The participants expressed shock and dissatisfaction due to an excessive invasion of privacy during the quarantine process and in the quarantine system. As confirmed COVID-19 cases, the participants experienced social stigma and feelings of guilt, negative attitudes from others and society, and negative influences from social networking services and the media. The participants also experienced mental and physical difficulties due to COVID-19 symptoms. However, they rediscovered meaningful relationships through the support of their family and friends in the midst of adversity. It is necessary to provide an integrated psychosocial rehabilitation program to reduce social stigma and improve the resilience of COVID-19 patients.

Can reactogenicity predict immunogenicity after COVID-19 vaccination?

BACKGROUND/AIMS: This study aimed to assess the association between local and systemic reactogenicity and humoral immunogenicity after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination. METHODS: Adverse events were prospectively evaluated using an electronic diary in 135 healthy adults who received a SARS-CoV-2 vaccine (AZD1222, AstraZeneca/Oxford, n = 42; or BNT162b2, Pfizer/BioNTech, n = 93). We semi-quantitatively measured anti-S1 immunoglobulin G (IgG) using an enzyme-linked immunosorbent assay at baseline, 3 weeks after the first dose of AZD1222 or BNT162b2, and 2 weeks after the second dose of BNT162b2. We evaluated the association between the maximum grade of local or systemic adverse events and the anti-S1 IgG optical density using multivariate linear regression with adjustment for age, sex, and use of antipyretics. RESULTS: The median age of the 135 vaccinees was 30 years (36 years in the AZD1222 group and 29 years in the BNT162b2 group) and 25.9% were male (9.5% in the AZD1222 group and 33.3% in the BNT162b2 group). Local and systemic adverse events were generally comparable after the first dose of AZD1222 and the second dose of BNT162b2. The grades of local and systemic adverse events were not significantly associated with anti-S1 IgG levels in the AZD1222 or BNT162b2 group. CONCLUSION: Local and systemic reactogenicity may not be associated with humoral immunogenicity after SARS-CoV-2 vaccination.

SARS-CoV-2 Genomic Variation in Space and Time in Hospitalized Patients in Philadelphia.

The severe acute respiratory coronavirus 2 (SARS-CoV-2) is the cause of the global outbreak of COVID-19. The epidemic accelerated in Philadelphia, PA, in the spring of 2020, with the city experiencing a first peak of infections on 15 April, followed by a decline through midsummer. Here, we investigate spread of the epidemic in the first wave in Philadelphia using full-genome sequencing of 52 SARS-CoV-2 samples obtained from 27 hospitalized patients collected between 30 March and 17 July 2020. Sequences most commonly resembled lineages circulating at earlier times in New York, suggesting transmission primarily from this location, though a minority of Philadelphia genomes matched sequences from other sites, suggesting additional introductions. Multiple genomes showed even closer matches to other Philadelphia isolates, suggestive of ongoing transmission within Philadelphia. We found that all of our isolates contained the D614G substitution in the viral spike and belong to lineages variously designated B.1, Nextstrain clade 20A or 20C, and GISAID clade G or GH. There were no viral sequence polymorphisms detectably associated with disease outcome. For some patients, genome sequences were determined longitudinally or concurrently from multiple body sites. In both cases, some comparisons showed reproducible polymorphisms, suggesting initial seeding with multiple variants and/or accumulation of polymorphisms after infection. These results thus provide data on the sources of SARS-CoV-2 infection in Philadelphia and begin to explore the dynamics within hospitalized patients.IMPORTANCE Understanding how SARS-CoV-2 spreads globally and within infected individuals is critical to the development of mitigation strategies. We found that most lineages in Philadelphia had resembled sequences from New York, suggesting infection primarily but not exclusively from this location. Many genomes had even nearer neighbors within Philadelphia, indicating local spread. Multiple genome sequences were available for some subjects and in a subset of cases could be shown to differ between time points and body sites within an individual, indicating heterogeneous viral populations within individuals and raising questions on the mechanisms responsible. There was no evidence that different lineages were associated with different outcomes in patients, emphasizing the importance of individual-specific vulnerability.