<b>Objectives</b><br/>This study presents the standardized protocols developed by the Clinical-Based Human Microbiome Research and Development Project (cHMP) in the Republic of Korea. <br/><b>Methods</b><br/>It addresses clinical metadata collection, specimen handling, DNA extraction, sequencing methods, and quality control measures for microbiome research. <br/><b>Results</b><br/>The cHMP involves collecting samples from healthy individuals and patients across various body sites, including the gastrointestinal tract, oral cavity, respiratory system, urogenital tract, and skin. These standardized procedures ensure consistent data quality through controlled specimen collection, storage, transportation, DNA extraction, and sequencing. Sequencing encompasses both amplicon and whole metagenome methods, followed by stringent quality checks. The protocols conform to international guidelines, ensuring that the data generated are both reliable and comparable across microbiome studies. <br/><b>Conclusion</b><br/>The cHMP underscores the importance of methodological standardization in enhancing data integrity, reproducibility, and advancing microbiome-based research with potential applications for improving human health outcomes.

<b>Objectives</b><br/>This study aimed to identify safe, conserved, and highly immunogenic epitopes from all proteins of human-infecting norovirus (NoV) and to design a multi-epitope subunit vaccine construct from these epitopes using an immunoinformatics approach. Additionally, the vaccine construct was evaluated using both sequence- and structure-based assessments. <br/><b>Methods</b><br/>Conserved fragments were identified from all proteins of human-infecting NoV, and B and T lymphocyte epitopes were subsequently predicted using multiple epitope prediction tools. The selected epitopes were linked to form a multi-epitope construct, incorporating various adjuvants in the design. Vaccine constructs with different adjuvants were analyzed for their physicochemical properties and immune simulation profiles, and the optimal combination was selected as the final vaccine candidate for further study. Finally, molecular docking and dynamics simulations were performed to visualize the interaction between the construct and a host immune receptor. <br/><b>Results</b><br/>Twenty-two safe, conserved, and highly immunogenic epitopes were identified from all human-infecting NoV proteins. The construct adjuvanted with 50S ribosomal protein L7/L12 (50SrpL7/L12) was chosen as the final vaccine candidate due to its optimal physicochemical properties and favorable immune simulation profile. Furthermore, the construct exhibited high binding affinity and a stable interaction with toll-like receptor 4). <br/><b>Conclusion</b><br/>The multi-epitope subunit vaccine designed in this study shows promise as a potential NoV vaccine candidate for human immunization. Further in vitro and in vivo experiments are warranted to validate these findings.

<b>Objectives</b><br/>This study investigated the relationship between metabolic factors (blood lipids and glucose) and inflammatory indicators (tumor necrosis factor-alpha [TNF-α] and high-sensitivity C-reactive protein [hs-CRP]), disease activity, and the rheumatoid arthritis (RA) risk. <br/><b>Methods</b><br/>Serum fasting blood glucose (FBG) and lipid profiles—including total cholesterol (Chol), triglycerides (TG), high-density lipoprotein (HDL), and low-density lipoprotein—were measured in 100 RA patients and 100 healthy individuals. Disease severity was assessed using the disease activity score 28. Inflammatory indicators (TNF-α and hs-CRP) were measured using the enzyme-linked immunosorbent assay method. <br/><b>Results</b><br/>In RA patients, serum FBG, TG, Chol/HDL, and TG/HDL were significantly elevated, whereas HDL levels reduced compared to healthy individuals. Multivariate analysis indicated that each unit increase in serum FBG, HDL, Chol/HDL, and TG/HDL was associated with a 64% increase (p<0.001), a 7% reduction (p=0.001), a 52% increase (p=0.007), and a 54% increase (p=0.001) in the odds of RA, respectively. Disease activity showed no correlation with metabolic factors (p>0.05). Among all metabolic factors studied, FBG had the largest area under the curve (0.981) (p<0.0001) for predicting RA. Across the total participant group, FBG, TG, and TG/HDL were positively associated with hs-CRP and TNF-α (p<0.05). HDL showed an inverse association with hs-CRP (p=0.008). Among RA patients specifically, TNF-α positively correlated with TG and TG/HDL, while hs-CRP correlated only with TG/HDL. <br/><b>Conclusion</b><br/>These findings indicate that increased FBG and Chol/HDL and decreased HDL may elevate RA risk by promoting systemic inflammation. Among these, elevated FBG may serve as the strongest predictor of RA risk.

<b>Objectives</b><br/>Subacute sclerosing panencephalitis (SSPE) is a rare but fatal neurodegenerative disease caused by persistent measles virus infection. After a significant measles outbreak in 2000–2001, the Republic of Korea implemented a nationwide measles elimination program, which led to a dramatic reduction in measles incidence. This study aimed to evaluate the impact of these measles elimination efforts on the incidence of SSPE in the Republic of Korea. <br/><b>Methods</b><br/>This nationwide, population-based retrospective cohort study identified patients newly diagnosed with measles and SSPE between 2007 and 2022, registered in the Health Insurance Review and Assessment Service (HIRA) and Korea Disease Control and Prevention Agency (KDCA) databases. Population-based incidence rates of measles and SSPE were calculated and compared annually. <br/><b>Results</b><br/>A total of 236 measles cases (HIRA data) and 1,168 measles cases (KDCA data), along with 2,736 SSPE cases, were diagnosed during the study period. Measles incidence significantly declined, reaching zero cases in 2021, while SSPE incidence displayed an upward trend, peaking in 2014. The mean age at SSPE onset was 21.2 years, with a marked male-to-female ratio of 13.0:1. <br/><b>Conclusion</b><br/>SSPE incidence was remarkably low in the post-outbreak period, likely attributable to successful measles control. This study underscores the critical importance of maintaining low measles incidence through sustained vaccination efforts, preventing SSPE and other measles-related complications.

<b>Objectives</b><br/>This study aimed to investigate the combined effects of individual, household, and community-level factors on coronavirus disease 2019 (COVID-19) vaccination intention using a multilevel analysis. Methods: This cross-sectional study analyzed raw data from the 2021 Korea Community Health Survey and regional statistics from 255 health centers, with a final sample of 229,216 individuals. Multilevel analysis was conducted, focusing on individual, household, and community-level factors. Individual-level factors included demographics, health status, and COVID-19 concerns; household-level factors included income and marital status; and community-level factors included city type and vaccination rates. Results: At the individual level, significant differences were observed across all variables. At the household level, higher vaccination intention was associated with households of 4 or more members and a monthly income of 4 million Korean won or more. At the community level, higher flu vaccination rates, greater concern about COVID-19 infection, and higher COVID-19 vaccination rates were linked to increased vaccination intention. Conclusion: This study highlights that COVID-19 vaccination intention is influenced by factors at the individual, household, and community levels. Vaccination strategies that integrate household and community-level approaches may be more effective. Policymakers should consider both individual and social health factors when designing vaccination policies.

<b>Objectives</b><br/>This study aimed to investigate the relationship between blood microbiota, specifically bacterial DNA, and cognitive decline in individuals with subjective cognitive decline (SCD) and amnestic mild cognitive impairment (aMCI). The objective was to identify potential microbial signatures that could serve as biomarkers for cognitive deterioration. Methods: Forty-seven participants were recruited, including 13 with aMCI, 20 with SCD, and 14 normal cognition (NC). Blood samples were collected, and microbial DNA was analyzed using 16S rRNA sequencing on the Illumina MiSeq platform. Bioinformatics analyses—including α- and β-diversity measures and differential abundance testing (using edgeR)—were employed to assess microbial diversity and differences in bacterial composition among groups. Logistic regression models were used to evaluate the predictive impact of the microbiota on cognitive decline. Results: Microbial diversity differed significantly between groups, with NC exhibiting the highest α-diversity. Both the aMCI and SCD groups showed reduced diversity. Taxa such as Bacteroidia, Alphaproteobacteria, and Clostridia were significantly decreased in the aMCI group compared to NC (p< 0.05). In contrast, Gammaproteobacteria increased significantly in the aMCI group compared to both NC and SCD, indicating progressive microbial changes from SCD to aMCI. No significant differences were found between the NC and SCD groups. Conclusion: Distinct bacterial taxa—particularly the increase in Gammaproteobacteria along with decreases in Bacteroidia, Alphaproteobacteria, and Clostridia—are associated with the progression of cognitive decline. These findings suggest that blood microbiota could serve as potential biomarkers for the early detection of aMCI. However, the small sample size and the lack of control for confounding factors such as diet and medication limit the findings. Larger studies are needed to validate these results and further explore the role of microbiota in neurodegeneration.

<b>Objectives</b><br/>This study aimed to explore factors influencing satisfaction with medical services among medically underserved populations at the free medical clinic, providing data to improve free medical services for these populations. Methods: We employed a descriptive correlational study design involving 112 individuals (aged 19 years and older) from medically underserved populations who visited the clinic. Data were collected through face-to-face surveys from September to October 2023, and statistical analyses (t-tests, analysis of variance, Pearson correlation, and hierarchical multiple regression) were used to identify key predictors of satisfaction. Results: Perceived support from healthcare providers emerged as the strongest predictor of satisfaction with medical services, demonstrating a significant positive association. While social support was positively correlated with perceived support from healthcare providers, it did not independently predict satisfaction. Conclusion: These findings underscore the importance of healthcare provider and social support in increasing satisfaction with medical services among medically underserved populations. Developing tailored healthcare programs and specialized healthcare provider training are essential strategies to improve healthcare access and outcomes for these vulnerable groups.

<b>Objectives</b><br/>This study aimed to describe and compare health-related quality of life (QoL) as measured by the World Health Organization Quality of Life–BREF (WHOQoL-BREF) and the EuroQol-5 Dimensions (EQ-5D) among the Malaysian population, examining differences by sociodemographic characteristics including age, income, sex, ethnicity, educational level, and occupation. Methods: This cross-sectional study used data from 19,402 individuals collected as part of a health and demographic surveillance system survey conducted in the Segamat district of Malaysia in 2018–2019. Descriptive statistics and measures of central tendency were produced. Differences in QoL among demographic sub-groups were examined using the t-test and analysis of variance, while the correlations between the WHOQoL-BREF and EQ-5D were evaluated using Pearson correlation coefficients. Results: Based on complete case analysis (n=19,129), the average scores for the 4 WHOQoLBREF domains were 28.2 (physical), 24.1 (psychological), 12.0 (social relationships), and 30.4 (environment). The percentages of participants not in full health for each EQ-5D dimension were 12.8% (mobility), 3.1% (self-care), 6.9% (usual activities), 20.9% (pain/discomfort), and 6.8% (anxiety/depression). Correlations between the 4 WHOQoL-BREF domains and the 5 EQ-5D dimensions were relatively weak, ranging from –0.06 (social relationships with self-care and pain/discomfort; p<0.001) to –0.42 (physical with mobility; p<0.001). Conclusion: Although health-related QoL as measured by the WHOQoL-BREF and the EQ-5D are correlated, these 2 measures should not be considered interchangeable. The choice between them should be guided by the specific research questions and the intended use of the data.

<b>Objectives</b><br/>This study systematically reviewed and analyzed epidemiological evidence regarding the association between dietary total antioxidant capacity (DTAC) and both the risk of developing diabetes and glycemic biomarker levels. <br/><b>Methods</b><br/>We searched the PubMed, Scopus, ScienceDirect, and Google Scholar databases through July 2024 without imposing any date restrictions. Original studies that examined the relationship between DTAC and either the risk of developing diabetes or glycemic biomarker levels—specifically fasting blood glucose (FBG), hemoglobin A1C (HbA1C), insulin, and the homeostatic model assessment for insulin resistance (HOMA-IR)—were eligible for inclusion. After eliminating duplicates and irrelevant records, relevant studies were selected, and data were extracted through rigorous critical analysis. <br/><b>Results</b><br/>A total of 32 articles were included in the review. Of the 19 studies that evaluated diabetes risk, 15 reported a lower risk among subjects with higher DTAC values. All 4 studies examining prediabetes risk found lower risk in participants with high DTAC scores. Additionally, significant inverse relationships were observed between DTAC values and FBG (9/15 studies), HbA1C (1/6 studies), insulin (5/6 studies), and HOMA-IR (8/9 studies). <br/><b>Conclusion</b><br/>The majority of evidence indicates that high adherence to an antioxidant-rich diet may reduce diabetes risk and improve glycemic biomarkers, including FBG, insulin, and HOMA-IR.

<b>Objectives</b><br/>Klebsiella pneumoniae is known as one of the most common causes of hospitalacquired infections. Its prevalence poses substantial challenges to both hospital and public health systems, particularly due to the rise of multidrug‐resistant strains. Understanding the epidemiology and resistance properties of K. pneumoniae can inform antimicrobial stewardship and infection control programs. A cross-sectional study was employed from November 2021 to November 2023. Methods: A total of 24 isolates underwent antimicrobial susceptibility testing using the disk diffusion method, an extended-spectrum beta-lactamase (ESBL) production test, and molecular gene detection. Results: The study found that 95.8% of clinical isolates were classified as multidrug-resistant. All isolates were resistant to ampicillin (100%). A high percentage of isolates were resistant to cefazolin (91.7%), ceftriaxone (87.5%), cefotaxime (87.5%), cefepime (87.5%), ciprofloxacin (83.3%), and sulfamethoxazole-trimethoprim (83.3%). Of the 24 isolates, 87.5% harbored ESBL genes, while the frequencies for GES, NDM, SIM, and OXA-48 were 16.7%, 20.8%, 8.3%, and 41.7%, respectively. Notably, the OXA-23 and OXA-51 genes, which are typically associated with Acinetobacter baumannii, were detected in 16.7% and 20.8% of isolates, respectively. Moreover, the prevalence of virulence genes rmpA, acrAB, and tolC was 0%, 95.8%, and 87.5%, respectively. Conclusion: This study demonstrated a high level of antibiotic resistance and a significant presence of virulence genes among K. pneumoniae isolates. Consequently, these findings represent a critical public health issue that requires heightened awareness among all stakeholders, including health workers.

This study aimed to establish a foundation for future collaborations aimed at preparing for and responding to infectious diseases by examining the vaccine injury compensation programs (VICPs) of East Asian countries. We reviewed the current status of VICPs in the Republic of Korea, Japan, and Taiwan by searching national government websites and reviewing relevant literature. Additionally, we conducted email inquiries targeting experts from Japan and Taiwan. Through the comprehensive analysis of VICPs in these 3 countries covered various aspects, we identified several similarities and differences in the VICPs across these countries. While the governments of the Republic of Korea, Japan, and Taiwan play a central role in supporting investigations into vaccine injuries and managing compensation procedures based on legal statutes, they differ in terms of financial resources for compensation, the range of vaccines covered, and the criteria for assessing causality. In the Republic of Korea, Japan, and Taiwan, compensation is typically paid in a lump sum, although the specific benefits available vary by country. This study on VICPs in the Republic of Korea, Japan, and Taiwan provides valuable insights for the further development and management of domestic systems.

<b>Objectives</b><br/>This study investigated factors influencing intentional self-harm in Chungcheongbuk Province (hereinafter, Chungbuk) compared to Seoul in the Republic of Korea. <br/><b>Methods</b><br/>Raw data from the Discharge In-depth Injury Survey conducted by the Korea Disease Control and Prevention Agency were utilized. From 2,329,149 cases recorded over 9 years (2013–2021), 911 were identified as intentional self-harm cases (248 from Chungbuk and 633 from Seoul). We analyzed the differences in and influencing factors of intentional self-harm in Chungbuk relative to Seoul using the independent sample t-test, chi-square test, and binomial logistic regression analysis. <br/><b>Results</b><br/>Intentional self-harm was found to be 1.232 times more prevalent among females than males (p<0.05); 2.327 times more prevalent among middle-aged and older adults, ages 50 to 64, compared to those under 50 years old (p<0.01); 8.603 times more prevalent among those using hospitals with fewer than 500 beds compared to those with 500 beds or more (p<0.001); 2.412 times more prevalent among individuals using hospitals in different regions compared to those within the same region (p<0.01); 2.217 times more prevalent among those attempting intentional self-harm during daily activities compared to other specified activities (p<0.01); and 6.987 times more prevalent among those using pesticides or herbicides compared to other poisons (p<0.001) in Chungbuk relative to Seoul. <br/><b>Conclusion</b><br/>In the Chungbuk region, intentional self-harm prevention programs should be implemented, specifically targeting women, particularly those aged 50 to 64. Additionally, due to the high incidence of intentional self-harm involving pesticides or herbicides in Chungbuk, these substances should be stringently monitored to restrict access.

<b>Objectives</b><br/>In this study, we performed comparative genomic and transcriptomic analysis of clinical isolates of Mycobacterium tuberculosis collected from patients with drug-susceptible tuberculosis (DS-TB). The clinical isolates were categorized based on treatment duration: standard 6 months or >6 months. <br/><b>Methods</b><br/>Study participants were recruited from a 2016 to 2018 tuberculosis cohort, and clinical M. tuberculosis isolates were collected from the sputum of patients with tuberculosis. We analyzed the genome and transcriptome of the isolated M. tuberculosis. <br/><b>Results</b><br/>Genomic analysis revealed a specific non-synonymous single-nucleotide polymorphism in pe_pgrs9 and ppe34, exclusive to the group treated for >6 months. Transcriptomic analysis revealed increased expression of various virulence-associated protein family genes and decreased expression of ribosomal protein genes and ppe38 genes in the group treated for >6 months. <br/><b>Conclusion</b><br/>The identified genetic variation and gene expression patterns may influence treatment outcomes by modulating host immune responses, increasing virulence, and potentially contributing to persister cell formation in M. tuberculosis. This study provides insights into the genetic and transcriptomic factors associated with prolonged DS-TB treatment. However, our study identified molecular characteristics using a small sample size, and further detailed studies are warranted.

<b>Objectives</b><br/>This study aimed to comprehensively outline the methodological approaches used in published research comparing the vaccine effectiveness (VE) of coronavirus disease 2019 (COVID-19) vaccines. <br/><b>Methods</b><br/>A systematic search was conducted on June 13, 2024, to identify comparative studies evaluating the effectiveness of mRNA versus non-mRNA and monovalent versus bivalent COVID-19 vaccines. We screened titles, abstracts, and full texts, collecting data on publication year, country, sample size, study population composition, study design, VE estimates, outcomes, and covariates. Studies that reported relative VE (rVE) were analyzed separately from those that did not. <br/><b>Results</b><br/>We identified 25 articles comparing rVE between mRNA and non-mRNA COVID-19 vaccines, as well as between monovalent and bivalent formulations. Among the studies assessing VE by vaccine type, 126 did not provide rVE estimates. Comparative VE studies frequently employed retrospective cohort designs. Among the definitions of rVE used, the most common were hazard ratio and absolute VE, calculated as (1−odds ratio)×100. Studies were most frequently conducted in the United Kingdom and the United States, and the most common outcome was infection. Most targeted the general population and assessed the VE of mRNA vaccines using the AstraZeneca vaccine as a reference. A small proportion, 7.3% (n=11), did not adjust for any variables. Only 3 studies (2.0%) adjusted for all core confounding variables recommended by the World Health Organization. <br/><b>Conclusion</b><br/>Few comparative studies of COVID-19 vaccines have incorporated rVE methodologies. Reporting rVE and employing a consistent set of covariates can broaden our understanding of COVID-19 vaccines.

<b>Objectives</b><br/>No study has yet analyzed risk factors to determine whether students with confirmed coronavirus disease 2019 (COVID-19) infections may affect students at neighboring schools. Therefore, this study aimed to determine risk factors for COVID-19 transmission among schools within a community in the Republic of Korea. <br/><b>Methods</b><br/>An epidemiological investigation was conducted among 696 students and school staff members at 3 schools where COVID-19 clusters began on October 15, 2021. Interviews, visit history surveys, a facility risk assessment, and closed-circuit television were used to identify risk factors. The statistical significance of risk factors was also evaluated. <br/><b>Results</b><br/>We confirmed 129 cases (18.5%) among the individuals exposed to COVID-19 at the 3 schools, many of whom had a history of visiting the same multi-use facilities. The odds ratio of having visited multi-use facilities such as karaoke rooms was 1.90 (95% confidence interval, 1.03–3.50); the number of visits to a karaoke room and the visit durations were significantly higher among confirmed cases than non-confirmed cases (p=0.02 and p=0.03, respectively). <br/><b>Conclusion</b><br/>Having a history of visiting karaoke rooms often and spending a long time there were risk factors for COVID-19 infection and inter-school transmission. Thus, it is necessary to investigate the status of multi-use facilities frequently visited by adolescents and consider incorporating them into the scope of school quarantine to prevent infectious diseases at schools in a community.