Purpose: The career ladder system is a pivotal strategy for securing excellent nurses. The aim of this study is to understand hospital nurses’ experiences of participating in the career ladder system and to explore the essence of this system. Methods: In February 22 to March 3, 2022, nurses employed at a general hospital in South Korea were selected for this study using snowball and purposive sampling. Data were collected from interviews with three focus groups, the compositions of which are as follows: group 1, 6 participants; group 2, 5 participants; and group 3, 6 participants. All interviews were recorded, transcribed verbatim, and subsequently analyzed using qualitative research methods. Results: The following six categories were derived under the overall theme of “the arduous journey to discovering a nurse’s true name”: (1) rites of passage to becoming the ideal nurse; (2) unexpected challenges in the promotion preparation process; (3) biased criteria for evaluating nursing competencies; (4) unclear changes in roles and perceptions after promotion; (5) self-discovered pride and fulfillment as a nurse; and (6) the unspoken struggles of evaluators. Conclusion The findings suggest that the career ladder system fosters nurses’ professional growth and self-actualization. However, for effective implementation, nurses’ deep understanding and systematic management of the career ladder system are essential. This study offers valuable insights and benchmarks for healthcare institutions aiming to adopt the system.

Purpose: The career ladder system is a pivotal strategy for securing excellent nurses. The aim of this study is to understand hospital nurses’ experiences of participating in the career ladder system and to explore the essence of this system. Methods: In February 22 to March 3, 2022, nurses employed at a general hospital in South Korea were selected for this study using snowball and purposive sampling. Data were collected from interviews with three focus groups, the compositions of which are as follows: group 1, 6 participants; group 2, 5 participants; and group 3, 6 participants. All interviews were recorded, transcribed verbatim, and subsequently analyzed using qualitative research methods. Results: The following six categories were derived under the overall theme of “the arduous journey to discovering a nurse’s true name”: (1) rites of passage to becoming the ideal nurse; (2) unexpected challenges in the promotion preparation process; (3) biased criteria for evaluating nursing competencies; (4) unclear changes in roles and perceptions after promotion; (5) self-discovered pride and fulfillment as a nurse; and (6) the unspoken struggles of evaluators. Conclusion The findings suggest that the career ladder system fosters nurses’ professional growth and self-actualization. However, for effective implementation, nurses’ deep understanding and systematic management of the career ladder system are essential. This study offers valuable insights and benchmarks for healthcare institutions aiming to adopt the system.

Purpose: The career ladder system is a pivotal strategy for securing excellent nurses. The aim of this study is to understand hospital nurses’ experiences of participating in the career ladder system and to explore the essence of this system. Methods: In February 22 to March 3, 2022, nurses employed at a general hospital in South Korea were selected for this study using snowball and purposive sampling. Data were collected from interviews with three focus groups, the compositions of which are as follows: group 1, 6 participants; group 2, 5 participants; and group 3, 6 participants. All interviews were recorded, transcribed verbatim, and subsequently analyzed using qualitative research methods. Results: The following six categories were derived under the overall theme of “the arduous journey to discovering a nurse’s true name”: (1) rites of passage to becoming the ideal nurse; (2) unexpected challenges in the promotion preparation process; (3) biased criteria for evaluating nursing competencies; (4) unclear changes in roles and perceptions after promotion; (5) self-discovered pride and fulfillment as a nurse; and (6) the unspoken struggles of evaluators. Conclusion The findings suggest that the career ladder system fosters nurses’ professional growth and self-actualization. However, for effective implementation, nurses’ deep understanding and systematic management of the career ladder system are essential. This study offers valuable insights and benchmarks for healthcare institutions aiming to adopt the system.

In the 2023–2024 season, the influenza epidemic in South Korea peaked earlier than in recent years. In this study, we aimed to estimate the interim vaccine effectiveness (VE) of the influenza vaccination to prevent influenza during the early season. From November 1, 2023, to December 31, 2023, we enrolled 2,632 subjects with influenza-like illness from eight hospitals participating in hospital-based influenza morbidity and mortality surveillance. A retrospective test-negative case-control study was conducted to estimate the VE. The results showed an adjusted VE of 22.5% (95% confidence interval [CI], 6.6 to 35.8) for the total population. The adjusted VE was 22.3% (95% CI, 6.1 to 35.7) for influenza A and 9.4% (95% CI, −51.3 to 45.7) for influenza A/H1N1. Full results of the analysis will be reported.

Background: Bivalent booster mRNA vaccines containing the omicron-variant strains have been introduced worldwide in the autumn of 2022. Nevertheless, the omicron subvariants evoked another large coronavirus disease 2019 (COVID-19) pandemic wave in late 2022 and early 2023. Methods: A retrospective, test-negative, case-control study was conducted to estimate the vaccine effectiveness (VE) of bivalent COVID-19 vaccines in 8 university hospitals between January and February 2023. The case and control groups were divided based on nasopharyngeal COVID-19 real-time polymerase chain reaction results and matched based on age, sex, hospital, and date (week) of the test performed. The VE of the BA.1- or BA.4/BA.5-based mRNA vaccines were estimated. VE was calculated using the 1−adjusted odds ratio from multivariable logistic regression. Results: In total, 949 patients and 947 controls were enrolled in this study. VE for the BA.4/ BA.5-based bivalent mRNA vaccine was 43% (95% confidence interval [CI], 17, 61%). In subgroup analysis based on age and underlying medical conditions, BA.4/BA.5-based bivalent mRNA vaccine was effective against old adults aged ≥ 65-years (VE, 55%; 95% CI, 23, 73%) and individuals with comorbidities (VE, 54%; 95% CI, 23, 73%). In comparison, the BA.1-based bivalent mRNA vaccine did not demonstrate statistically significant effectiveness (VE, 25%; 95% CI, −8, 49%). Conclusion The BA.4/BA.5-based bivalent mRNA booster vaccine provided significant protection against COVID-19 in the Korean adults, especially in the older adults aged ≥ 65 years and in individuals with underlying medical conditions.

Background: This study aimed to determine the effect of ramen sauce on tooth tone changes over time, after selecting three different ramen colors from the ramens sold in the market, and applying the sauce to bovine teeth. Methods: Healthy bovine teeth were selected, and cutting discs were used to produce 60 specimens (5×5×3 mm), with 15 specimens distributed per county. Three types of ramen (buldak, chacharoni black bean sauce, and ottogi curry noodle) were used as the experimental group, and water was used as the negative control group. Tooth tone measurement was performed using a spectrophotometer (CM-700d) to measure the color before and after 1 (3 h 44 min), 2 (7 h 28 min), 3 (11 h 12 min), and 4 weeks (14 h 56 min). Analysis of the color tone change was performed using Statistical Package for the Social Sciences version 28. Results: In the experimental group, there was a significant color tone change before and after immersion. L* indicated the largest change in black bean sauce ramen, a* indicated buldak ramen, and b* indicated the largest change in curry ramen. The amount of color change (ΔE*) was the largest in curry ramen, followed by buldak and black bean sauce ramens. The results of the post-hoc analysis showed significant differences between all groups except buldak and black bean sauce ramens. Conclusion All three types of ramen revealed significant color change before and after immersion, and curry ramen showed the largest amount of color change among them.

OBJECTIVES: We estimated the population prevalence of antibodies to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), including unreported infections, through a Korea Seroprevalence Study of Monitoring of SARS-CoV-2 Antibody Retention and Transmission (K-SEROSMART) in 258 communities throughout Korea. METHODS: In August 2022, a survey was conducted among 10,000 household members aged 5 years and older, in households selected through two stage probability random sampling. During face-to-face household interviews, participants self-reported their health status, COVID-19 diagnosis and vaccination history, and general characteristics. Subsequently, participants visited a community health center or medical clinic for blood sampling. Blood samples were analyzed for the presence of antibodies to spike proteins (anti-S) and antibodies to nucleocapsid proteins (anti-N) SARS-CoV-2 proteins using an electrochemiluminescence immunoassay. To estimate the population prevalence, the PROC SURVEYMEANS statistical procedure was employed, with weighting to reflect demographic data from July 2022. RESULTS: In total, 9,945 individuals from 5,041 households were surveyed across 258 communities, representing all basic local governments in Korea. The overall population-adjusted prevalence rates of anti-S and anti-N were 97.6% and 57.1%, respectively. Since the Korea Disease Control and Prevention Agency has reported a cumulative incidence of confirmed cases of 37.8% through July 31, 2022, the proportion of unreported infections among all COVID-19 infection was suggested to be 33.9%. CONCLUSIONS The K-SEROSMART represents the first nationwide, community-based seroepidemiologic survey of COVID-19, confirming that most individuals possess antibodies to SARS-CoV-2 and that a significant number of unreported cases existed. Furthermore, this study lays the foundation for a surveillance system to continuously monitor transmission at the community level and the response to COVID-19.

Background: We assessed the myocardial infarction (MI), stroke, and all-cause death risks during follow-up according to the low-density lipoprotein cholesterol (LDL-C) levels among older adults. Methods: The Korean National Health Insurance Service datasets (2002 to 2020) were used for this population-based cohort study. The hazards of MI, stroke, and all-cause mortality during follow-up were analyzed according to LDL-C level in individuals aged ≥65 years without baseline cardiovascular diseases (n=1,391,616). Results: During a mean 7.55 years, 52,753 MIs developed; 84,224 strokes occurred over a mean 7.47 years. After a mean 8.50 years, 233,963 died. A decrease in LDL-C was associated with lower hazards of MI and stroke. The decreased hazard of stroke in lower LDL-C was more pronounced in statin users, and individuals with diabetes or obesity. The hazard of all-cause death during follow-up showed an inverted J-shaped pattern according to the LDL-C levels. However, the paradoxically increased hazard of mortality during follow-up in lower LDL-C was attenuated in statin users and individuals with diabetes, hypertension, or obesity. In statin users, lower LDL-C was associated with a decreased hazard of mortality during follow-up. Conclusion Among the elderly, lower LDL-C was associated with decreased risks of MI and stroke. Lower LDL-C achieved by statins in the elderly was associated with a decreased risk of all-cause death during follow-up, suggesting that LDL-C paradox for the premature death risk in the elderly should not be applied to statin users. Intensive statin therapy should not be hesitated for older adults with cardiovascular risk factors including diabetes.

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.

Background: As the coronavirus disease 2019 (COVID-19) pandemic continues, there are concerns regarding waning immunity and the emergence of viral variants. The immunogenicity of Ad26.COV2.S against wild-type (WT) and variants of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) needs to be evaluated.Method: This prospective cohort study was conducted between June 2021 and January 2022 at two university hospitals in South Korea. Healthy adults who were scheduled to be vaccinated with Ad26.COV2.S were enrolled in this study. The main outcomes included anti-spike (S) IgG antibody and neutralizing antibody responses, S-specific T-cell responses (interferon-γ enzyme-linked immunospot assay), solicited adverse events (AEs), and serious AEs. Results: Fifty participants aged ≥ 19 years were included in the study. Geometric mean titers (GMTs) of anti-S IgG were 0.4 U/mL at baseline, 5.2 ± 3.0 U/mL at 3–4 weeks, 55.7 ± 2.4 U/mL at 5–8 weeks, and 81.3 ± 2.5 U/mL at 10–12 weeks after vaccination. GMTs of 50% neutralizing dilution (ND50) against WT SARS-CoV-2 were 164.6 ± 4.6 at 3-4 weeks, 313.9 ± 3.6 at 5–8 weeks, and 124.4 ± 2.6 at 10–12 weeks after vaccination. As for the S-specific T-cell responses, the median number of spot-forming units/10 6 peripheral blood mononuclear cell was 25.0 (5.0–29.2) at baseline, 60.0 (23.3–178.3) at 5-8 weeks, and 35.0 (13.3–71.7) at 10–12 weeks after vaccination. Compared to WT SARS-CoV-2, ND50 against Delta and Omicron variants was attenuated by 3.6-fold and 8.2-fold, respectively. The most frequent AE was injection site pain (82%), followed by myalgia (80%), fatigue (70%), and fever (50%). Most AEs were grade 1–2, and resolved within two days. Conclusion Single-dose Ad26.COV2.S was safe and immunogenic. NAb titer and S-specific T-cell immunity peak at 5–8 weeks and rather decrease at 10–12 weeks after vaccination.Cross-reactive neutralizing activity against the Omicron variant was negligible.