The Korean Society of Infectious Diseases has been regularly publishing guidelines for adult immunization since 2007. Following the release of coronavirus disease 2019 (COVID-19) vaccination recommendations in 2023, significant changes have occurred due to the emergence of new variant strains and the waning immunity from previous vaccinations. This article provides a comprehensive update as of November 2024, incorporating the latest evidence and guidelines. Focusing on the 2024–2025 season, this article reviews vaccines currently authorized in Korea and assesses their effectiveness against the predominant JN.1 lineage variants. The updated recommendations prioritize high-risk groups, including adults aged 65 and older, individuals with underlying medical conditions, residents of facilities vulnerable to infection, pregnant women, and healthcare workers, for vaccination with updated vaccines targeting the JN.1 strain. Additionally, COVID-19 vaccination is available for all individuals aged 6 months and older. For most adults, a single-dose strategy is emphasized, while tailored schedules may be recommended for immunocompromised individuals. This update aims to optimize vaccination strategies in Korea to ensure comprehensive protection for high-risk populations.

The Korean Society of Infectious Diseases has been regularly publishing guidelines for adult immunization since 2007. Following the release of coronavirus disease 2019 (COVID-19) vaccination recommendations in 2023, significant changes have occurred due to the emergence of new variant strains and the waning immunity from previous vaccinations. This article provides a comprehensive update as of November 2024, incorporating the latest evidence and guidelines. Focusing on the 2024–2025 season, this article reviews vaccines currently authorized in Korea and assesses their effectiveness against the predominant JN.1 lineage variants. The updated recommendations prioritize high-risk groups, including adults aged 65 and older, individuals with underlying medical conditions, residents of facilities vulnerable to infection, pregnant women, and healthcare workers, for vaccination with updated vaccines targeting the JN.1 strain. Additionally, COVID-19 vaccination is available for all individuals aged 6 months and older. For most adults, a single-dose strategy is emphasized, while tailored schedules may be recommended for immunocompromised individuals. This update aims to optimize vaccination strategies in Korea to ensure comprehensive protection for high-risk populations.

The Korean Society of Infectious Diseases has been regularly publishing guidelines for adult immunization since 2007. Following the release of coronavirus disease 2019 (COVID-19) vaccination recommendations in 2023, significant changes have occurred due to the emergence of new variant strains and the waning immunity from previous vaccinations. This article provides a comprehensive update as of November 2024, incorporating the latest evidence and guidelines. Focusing on the 2024–2025 season, this article reviews vaccines currently authorized in Korea and assesses their effectiveness against the predominant JN.1 lineage variants. The updated recommendations prioritize high-risk groups, including adults aged 65 and older, individuals with underlying medical conditions, residents of facilities vulnerable to infection, pregnant women, and healthcare workers, for vaccination with updated vaccines targeting the JN.1 strain. Additionally, COVID-19 vaccination is available for all individuals aged 6 months and older. For most adults, a single-dose strategy is emphasized, while tailored schedules may be recommended for immunocompromised individuals. This update aims to optimize vaccination strategies in Korea to ensure comprehensive protection for high-risk populations.

Background: To analyze the effects of socioeconomic status (type of insurance and income level) and cancer stage on the survival of patients with liver cancer in Korea. Methods: A retrospective cohort study was constructed using data from the Healthcare Big Data Platform project in Korea between January 1, 2007, and December 31, 2017. A total of 143,511 patients in Korea diagnosed with liver cancer (International Classification of Diseases, 10th Revision [ICD-10] codes C22, C220, and C221) were followed for an average of 11 years. Of these, 110,443 died. The patient’s insurance type and income level were used as indicators of socioeconomic status. Unadjusted and adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated using a Cox proportional hazards regression model to analyze the relationship between the effects of sex, age, and cancer stage at first diagnosis (Surveillance, Epidemiology, and the End Results; SEER), type of insurance, and income level on the survival of patients with liver cancer. The interactive effects of the type of insurance, income level, and cancer stage on liver cancer death were also analyzed. Results: The lowest income group (medical aid) showed a higher risk for mortality (HR (95% CI); 1.37 (1.27–1.47) for all patients, 1.44 (1.32–1.57) for men, and 1.16 (1.01–1.34) for women) compared to the highest income group (1–6) among liver cancer (ICD-10 code C22) patients. The risk of liver cancer death was also higher in the lowest income group with a distant cancer stage (SEER = 7) diagnosis than for any other group. Conclusion Liver cancer patients with lower socioeconomic status and more severe cancer stages were at greater risk of death. Reducing social inequalities is needed to improve mortality rates among patients in lower social class groups who present with advanced cancer.

Background: The benefits of transradial access (TRA) over transfemoral access (TFA) for bifurcation percutaneous coronary intervention (PCI) are uncertain because of the limited availability of device selection. This study aimed to compare the procedural differences and the in-hospital and long-term outcomes of TRA and TFA for bifurcation PCI using secondgeneration drug-eluting stents (DESs). Methods: Based on data from the Coronary Bifurcation Stenting Registry III, a retrospective registry of 2,648 patients undergoing bifurcation PCI with second-generation DES from 21 centers in South Korea, patients were categorized into the TRA group (n = 1,507) or the TFA group (n = 1,141). After propensity score matching (PSM), procedural differences, in-hospital outcomes, and device-oriented composite outcomes (DOCOs; a composite of cardiac death, target vessel-related myocardial infarction, and target lesion revascularization) were compared between the two groups (772 matched patients each group). Results: Despite well-balanced baseline clinical and lesion characteristics after PSM, the use of the two-stent strategy (14.2% vs. 23.7%, P = 0.001) and the incidence of in-hospital adverse outcomes, primarily driven by access site complications (2.2% vs. 4.4%, P = 0.015), were significantly lower in the TRA group than in the TFA group. At the 5-year follow-up, the incidence of DOCOs was similar between the groups (6.3% vs. 7.1%, P = 0.639). Conclusion The findings suggested that TRA may be safer than TFA for bifurcation PCI using second-generation DESs. Despite differences in treatment strategy, TRA was associated with similar long-term clinical outcomes as those of TFA. Therefore, TRA might be the preferred access for bifurcation PCI using second-generation DES.

Background: Exercise capacity is associated with lung function decline in chronicobstructive pulmonary disease (COPD) patients, but a discrepancy between exercisecapacity and airflow limitation exists. This study aimed to explore factors contributingto this discrepancy in COPD patients. Methods: Data for this prospective study were obtained from the Korean COPD SubgroupStudy. The exercise capacity and airflow limitation were assessed using the6-minute walk distance (6-MWD; m) and forced expiratory volume in 1 second (FEV1).Participants were divided into four groups: FEV1 >50%+6-MWD >350, FEV1 >50%+6-MWD ≤350, FEV1 ≤50%+6-MWD >350, and FEV1 ≤50%+6-MWD ≤350 and their clinicalcharacteristics were compared. Results: A total of 883 patients (male:female, 822:61; mean age, 68.3±7.97 years) wereenrolled. Among 591 patients with FEV1 >50%, 242 were in the 6-MWD ≤350 group, andamong 292 patients with FEV1 ≤50%, 185 were in the 6-MWD >350 group. The multipleregression analyses revealed that male sex (odds ratio [OR], 8.779; 95% confidence interval[CI], 1.539 to 50.087; p=0.014), current smoking status (OR, 0.355; 95% CI, 0.178to 0.709; p=0.003), and hemoglobin levels (OR, 1.332; 95% CI, 1.077 to 1.648; p=0.008)were significantly associated with discrepancies in exercise capacity and airflow limitationin patients with FEV1 >50%. Meanwhile, in patients with FEV1 ≤50%, diffusioncapacity of carbon monoxide (OR, 0.945; 95% CI, 0.912 to 0.979; p=0.002) was significantlyassociated with discrepancies between exercise capacity and airflow limitation. Conclusion The exercise capacity of COPD patients may be influenced by factors otherthan airflow limitation, so these aspects should be considered when assessing andtreating patients.

Background: Antimicrobial prescriptions for serious chronic or acute illness nearing its end stages raise concerns about the potential for futile use, adverse events, increased multidrugresistant organisms, and significant patient and social cost burdens. This study investigated the nationwide situation of how antibiotics are prescribed to patients during the last 14 days of life to guide future actions. Methods: This nationwide multicenter retrospective cohort study was conducted at 13 hospitals in South Korea from November 1 to December 31, 2018. All decedents were included in the study. Antibiotic use during the last two weeks of their lives was investigated. Results: A total of 1,201 (88.9%) patients received a median of two antimicrobial agents during the last two weeks of their lives. Carbapenems were prescribed to approximately half of the patients (44.4%) in the highest amount (301.2 days of therapy per 1,000 patient-days).Among the patients receiving antimicrobial agents, 63.6% were inappropriate and only 327 patients (27.2%) were referred by infectious disease specialists. The use of carbapenem (odds ratio [OR], 1.51; 95% confidence interval [CI], 1.13–2.03; P = 0.006), underlying cancer (OR, 1.56; 95% CI, 1.20–2.01, P = 0.047), underlying cerebrovascular disease (OR, 1.88; 95% CI, 1.23–2.89, P = 0.004), and no microbiological testing (OR, 1.79; 95% CI, 1.15–2.73; P = 0.010) were independent predictors for inappropriate antibiotic prescribing. Conclusion A considerable number of antimicrobial agents are administered to patients with chronic or acute illnesses nearing their end-of-life, a high proportion of which are prescribed inappropriately. Consultation with an infectious disease specialist, in addition to an antimicrobial stewardship program, may be necessary to induce the optimal use of antibiotics.

Despite the availability of direct-acting antivirals (DAAs) for chronic hepatitis C virus (HCV) infection in Korea, need remains for pangenotypic regimens that can be used in the presence of hepatic impairment, comorbidities, or prior treatment failure. We investigated the efficacy and safety of sofosbuvir–velpatasvir and sofosbuvir–velpatasvir–voxilaprevir for 12 weeks in HCV-infected Korean adults. Methods: This Phase 3b, multicenter, open-label study included 2 cohorts. In Cohort 1, participants with HCV genotype 1 or 2 and who were treatment-naive or treatment-experienced with interferon-based treatments, received sofosbuvir–velpatasvir 400/100 mg/day. In Cohort 2, HCV genotype 1 infected individuals who previously received an NS5A inhibitor-containing regimen ≥ 4 weeks received sofosbuvir–velpatasvir–voxilaprevir 400/100/100 mg/day. Decompensated cirrhosis was an exclusion criterion. The primary endpoint was SVR12, defined as HCV RNA < 15 IU/mL 12 weeks following treatment. Results: Of 53 participants receiving sofosbuvir–velpatasvir, 52 (98.1%) achieved SVR12. The single participant who did not achieve SVR12 experienced an asymptomatic Grade 3 ASL/ALT elevation on day 15 and discontinued treatment. The event resolved without intervention. All 33 participants (100%) treated with sofosbuvir–velpatasvir–voxilaprevir achieved SVR 12. Overall, sofosbuvir–velpatasvir and sofosbuvir–velpatasvir–voxilaprevir were safe and well tolerated. Three participants (5.6%) in Cohort 1 and 1 participant (3.0%) in Cohort 2 had serious adverse events, but none were considered treatment-related. No deaths or grade 4 laboratory abnormalities were reported. Conclusions: Treatment with sofosbuvir–velpatasvir or sofosbuvir–velpatasvir–voxilaprevir was safe and resulted in high SVR12 rates in Korean HCV patients.

Background: This study aimed to investigate the prevalence rate of hepatitis C virus (HCV) infection and identify the demographic, and sociological characteristics and changes in awareness of HCV infection by participating the study for North Korean defectors residing in South Korea. Methods: This study prospectively enrolled participants. Demographic, sociological and clinical data, and questionnaire surveys focused on awareness of HCV infection were collected. Results: In total, 211 North Korean defectors participated in this study from September 2020 until June 2021. There were 174 women (82.5%), and the overall mean age was 48.9 years (range, 20 to 80 years). Of these participants, 112 (53.1%) had immigrated to South Korea since 2011. The overall prevalence of anti-HCV antibody among North Korean defectors was 1.9%. Thirty participants (14.2%) had hepatitis B surface antigens. A huge lack of awareness regarding HCV infection has been observed among North Korean defectors. Conclusion This is the first prospective study to investigate the prevalence rate of HCV infection among North Korean defectors residing in South Korea. As North Korean defectors are a vulnerable group concerning HCV infection, they may benefit from HCV screening policies and educational interventions for HCV infection.

Background: This study aimed to determine whether serum uric acid (SUA) levels are associated with various indices of liver damage in the adult Korean population. Methods: We used the Seventh (VII) Korean National Health and Nutritional Examination Surveys. Our study population comprised 6,007 men and 8,488 women. Levels of SUA were divided into four groups (≤ 5.3, 5.3–6.0, 6.0–7.0, and > 7.0 mg/dL for men and ≤ 4.0, 4.0–4.8, 4.8–6.0, and > 6.0 mg/dL for women). Elevated liver enzyme levels were defined as > 35 (men) and > 31 (women) IU/L for aspartate aminotransferase (AST), > 45 (men) and > 34 (women) IU/L for alanine aminotransferase (ALT). Hepatic steatosis index and fibrosis (FIB)-4 index was used to determine nonalcoholic fatty liver disease (NAFLD) and liver FIB, respectively. Adjusted odds ratios (aORs) were calculated by logistic regression analysis for liver enzymes, NAFLD, and liver FIB, according to the SUA level. Results: Among women, the 4.8–6.0 and > 6.0 mg/dL SUA groups showed higher ORs of elevated AST (aOR, 1.78 and 2.03; 95% confidence interval [CI], 1.37–2.32 and 1.40–2.96, respectively; P < 0.001) and the 4.0–4.8, 4.8–6.0, and > 6.0 mg/dL SUA groups showed a higher ORs of ALT elevation (aOR, 1.35, 2.26, and 2.37; 95% CI, 1.02–1.79, 1.72–2.97, and 1.60–3.50, respectively; P < 0.001) compared to the lowest level SUA group. Among women with normal ALT, > 6.0 mg/dL SUA group showed higher OR of NAFLD status (aOR, 1.52; 95% CI, 1.06–2.19). Among men and women with NAFLD, hyperuricemia showed higher ORs of liver FIB (aOR, 2.25 and 1.89; 95% CI, 1.21–4.19 and 1.09–3.27, respectively) than the lowest level SUA group. Conclusion High SUA levels may be associated with elevated liver enzymes and NAFLD, mainly in women. Even in women with normal ALT levels, SUA levels may predict the NAFLD status. Hyperuricemia may predict advanced liver FIB in both men and women with NAFLD. Further studies investigating the causal effects of SUA on liver damage are required.