1.A multi-city outbreak of Salmonella Enteritidis infections linked to bakery products, Republic of Korea
Da Seul KIM ; Soon-Young SEO ; Dong Hwi KIM ; Yeon Hee WOO ; Deborah LEE ; Se Jeong YANG ; Junyoung KIM ; Eunkyung SHIN ; Byungsun JUNG ; Eunmi LEE ; Min Jung LEE ; Young-Joon PARK
Osong Public Health and Research Perspectives 2026;17(1):61-71
Objectives:
In May 2025, clusters of salmonellosis were identified in 7 cities in the Republic of Korea, all associated with consumption of identical bakery products. This investigation aimed to characterize the outbreak, identify potential contributing factors, and inform strategies for preventing similar multi-facility foodborne outbreaks.
Methods:
A case series study was conducted among individuals who consumed Manufacturer H’s Product I and Product II on May 15–16, 2025 at 7 facilities (n = 1,235). Clinical specimens from symptomatic individuals, retained food samples, and environmental samples were collected and tested. Food-exposure histories were assessed, and active case finding was implemented across all supplied facilities. Traceback investigations were conducted at the manufacturer, distributor, and egg farms. Human and food isolates underwent pulsed-field gel electrophoresis (PFGE) and whole-genome sequencing (WGS).
Results:
A total of 323 cases met the outbreak case definition (attack rate, 26.2%), of which 48 were laboratory-confirmed. Salmonella Enteritidis was isolated from both clinical specimens and retained bakery products. PFGE patterns were indistinguishable between human and food isolates, and WGS demonstrated high genetic relatedness. These findings confirmed a common-source outbreak linked to the implicated bakery products.
Conclusion
This outbreak underscores the value of integrating epidemiological investigation, active case finding, and molecular typing to identify common food vehicles in outbreaks involving widely distributed manufactured foods. Coordinated collaboration between public health and food safety authorities is essential for the effective detection, response, and prevention of multi-facility foodborne outbreaks.
2.Effect of Subepithelial Pterygium Pedicle Length on Anterior Corneal Keratometry and Wavefront Aberrations
Eunkyung JANG ; Seung Hyeun LEE ; Kyoung Woo KIM
Korean Journal of Ophthalmology 2026;40(2):176-184
Purpose:
To introduce subepithelial pterygium pedicle (SPP) and to investigate the effect of SPP length on the anterior corneal curvature including keratometry and aberrations.
Methods:
In this single-center retrospective cohort, 72 eyes of 72 patients with primary nasal pterygium were analyzed using anterior segment (AS) swept-source optical coherence tomography (SS-OCT; Anterion). We evaluated SPP length, horizontal invasion length (HIL), and corneal profiles including keratometry, root mean square values for lower- and higher-order aberrations, and first- to fourth-order wavefront aberrations. Correlations between SPP length and these parameters were assessed after adjusting for HIL. The SPP cutoff for significant anterior horizontal tilt deterioration was determined using receiver operating characteristic (ROC) analysis and validated by analysis of covariance controlling for HIL.
Results:
SPP was detected in 57 of 72 eyes (79.2%), with a mean length of 842.3 ± 408.1 μm. A significant positive correlation was found between SPP length and HIL (r = 0.376, p = 0.001). After adjusting for HIL, SPP length remained significantly associated with anterior corneal horizontal tilt (p = 0.026), whereas no significant correlations were observed with other refractive or aberration parameters. ROC curve analysis identified an SPP length of approximately 850 μm as the threshold for predicting anterior horizontal tilt ≥3.65 μm. Consequently, this cutoff significantly differentiated subgroups after adjusting for HIL, showing a marked increase in horizontal tilt in eyes with SPP ≥850 μm (p = 0.016), indicating mechanical distortion.
Conclusions
SPP length, a subepithelial microstructural parameter visualized by AS SS-OCT, independently correlates with anterior horizontal tilt after adjustment for HIL. This finding suggests that SPP length serves as a microstructural indicator of horizontal mechanical corneal distortion in eyes with pterygium.
3.Comparison of Suicide Completion Rate in Korean Students Pre- and Post-COVID-19 Pandemics
Kyungjin LEE ; Boram NAM ; Kyoil SEO ; Eunkyung JO ; Seohyun KIM ; Deokyong SHIN ; Aeju KIM ; Youngil JEONG ; Yeni KIM
Psychiatry Investigation 2025;22(2):204-211
Objective:
This study compared the incidence of suicide cases among Korean students before and after the coronavirus disease-2019 (COVID-19) pandemic.
Methods:
Aggregated case reports of all known suicide victims attending elementary, middle, and high school in South Korea from 2017 to 2022 were analyzed. These reports, compiled by teachers under the directive of the South Korean Department of Education, surveyed the circumstances surrounding each suicide and identified associated risk factors posthumously.
Results:
The completed suicide rate was 2.37 per 100,000 students pre-COVID-19 (2017–2019), significantly increasing to 3.37 per 100,000 students post-COVID-19 (2020–2022; odds ratio [OR] 1.42, p<0.001). The rate began to rise approximately 6 months into the pandemic and continued to worsen throughout 2021 and 2022. Fair attendance significantly increased in 2020 (74.83%, p=0.003) during the initial stage of school closure measures compared to 2019 (58.27%) among students prior to suicide completion. However, as social distancing measures continued, “absence due to medical reasons” showed a significant increase in 2022 (23.56%) compared to 2019 (13.67%, p=0.025) and 2020 (9.52%, p<0.001) among these students. Among those who completed suicide, teachers reported increased signs of depression and anxiety posthumously compared to pre-COVID-19 periods.
Conclusion
The incidence of completed suicide among students was significantly higher in the post-COVID-19 years compared to pre-COVID-19. Attendance records and teachers’ reports indicated a deterioration in mental health among these students before suicide completion, highlighting the need to consider mental health impacts when implementing future quarantine policies.
4.Network Structure of Depression and Anxiety Symptoms in Older Asian Patients With Depressive Disorders: Findings From REAP-AD3
Seon-Cheol PARK ; Kiwon KIM ; Jeongsoo PARK ; Sun CHOI ; Seonhwa LEE ; Seungwon CHO ; Eunkyung KIM ; Tian-Mei SI ; Roy Abraham KALLIVAYALIL ; Andi J. TANRA ; Amir Hossein Jalali NADOUSHAN ; Kok Yoon CHEE ; Afzal JAVED ; Kang SIM ; Pornjira PARIWATCHARAKUL ; Takahiro A. KATO ; Shih-Ku LIN ; Naotaka SHINFUKU ; Norman SARTORIUS
Psychiatry Investigation 2025;22(5):552-563
Objective:
The clinical presentation of depressive disorders might be influenced by age, and its diagnosis and treatment can be affected by ageism-related bias. A network analysis can reveal symptom patterns unrecognized by the reductionistic approach. Therefore, this study explores the network structure of depression and anxiety symptoms in older Asian patients with depressive disorders and examines age-related differences in the context of ageism.
Methods:
We used data from the Research on Asian Psychotropic Prescription Patterns for Antidepressants, Phase 3 study and included 2,785 psychiatric patients from 11 Asian countries. Depression and anxiety symptoms were assessed using the Patient Health Questionnaire-9 and Generalized Anxiety Disorder-7. Network analyses were conducted to identify symptom interconnections and centrality among older (>65 years), middle-aged (35–64 years), and young (18–34 years) adult groups. The network structures were also compared using a network comparison test.
Results:
Depressed mood was the most central symptom across all age groups. Network comparisons revealed no significant structural differences among the three age groups, despite several variations in terms of global strength. The network structure of the older group was characterized by strong interconnections between somatic symptoms (insomnia-energy) and core depressive symptoms (little interest or pleasure-feelings of hopelessness).
Conclusion
This study reveals that the network structures of depression and anxiety symptoms have relatively consistent interconnections across age groups, despite subtle age-based differences. Specifically, older adults tend to present anxiety and depression symptoms as physical complaints. These findings challenge ageist stereotypes and advocate for inclusive, age-neutral approaches to treatment.
5.Poor Prognosis of Pneumococcal Co-Infection in Hospitalized Patients with COVID-19: A Propensity Score-Matched Analysis
Soyoon HWANG ; Eunkyung NAM ; Shin-Woo KIM ; Hyun-Ha CHANG ; Yoonjung KIM ; Sohyun BAE ; Nan Young LEE ; Yu Kyung KIM ; Ji Sun KIM ; Han Wook PARK ; Joon Gyu BAE ; Juhwan JEONG ; Ki Tae KWON
Infection and Chemotherapy 2025;57(1):172-178
The impact of Streptococcus pneumoniae coinfection on coronavirus disease 2019 (COVID-19) prognosis remains uncertain. We conducted a retrospective analysis of patients hospitalized with COVID-19 who underwent a pneumococcal urinary antigen (PUA) test to assess its clinical utility. Results showed that PUA-positive patients required more oxygen support, high-flow nasal cannula, and dexamethasone compared to PUA-negative patients.Furthermore, the significantly higher incidence of a National Early Warning Score ≥5 in the PUA-positive group (P<0.001) suggests that a positive PUA test is associated with a severe disease course. However, no significant difference in mortality was observed between the two groups, and antibiotics were used in almost all patients (96.2%). While the PUA test may help guide antibiotic use in COVID-19 patients, its interpretation should be approached with caution.
6.Comparison of Suicide Completion Rate in Korean Students Pre- and Post-COVID-19 Pandemics
Kyungjin LEE ; Boram NAM ; Kyoil SEO ; Eunkyung JO ; Seohyun KIM ; Deokyong SHIN ; Aeju KIM ; Youngil JEONG ; Yeni KIM
Psychiatry Investigation 2025;22(2):204-211
Objective:
This study compared the incidence of suicide cases among Korean students before and after the coronavirus disease-2019 (COVID-19) pandemic.
Methods:
Aggregated case reports of all known suicide victims attending elementary, middle, and high school in South Korea from 2017 to 2022 were analyzed. These reports, compiled by teachers under the directive of the South Korean Department of Education, surveyed the circumstances surrounding each suicide and identified associated risk factors posthumously.
Results:
The completed suicide rate was 2.37 per 100,000 students pre-COVID-19 (2017–2019), significantly increasing to 3.37 per 100,000 students post-COVID-19 (2020–2022; odds ratio [OR] 1.42, p<0.001). The rate began to rise approximately 6 months into the pandemic and continued to worsen throughout 2021 and 2022. Fair attendance significantly increased in 2020 (74.83%, p=0.003) during the initial stage of school closure measures compared to 2019 (58.27%) among students prior to suicide completion. However, as social distancing measures continued, “absence due to medical reasons” showed a significant increase in 2022 (23.56%) compared to 2019 (13.67%, p=0.025) and 2020 (9.52%, p<0.001) among these students. Among those who completed suicide, teachers reported increased signs of depression and anxiety posthumously compared to pre-COVID-19 periods.
Conclusion
The incidence of completed suicide among students was significantly higher in the post-COVID-19 years compared to pre-COVID-19. Attendance records and teachers’ reports indicated a deterioration in mental health among these students before suicide completion, highlighting the need to consider mental health impacts when implementing future quarantine policies.
7.Network Structure of Depression and Anxiety Symptoms in Older Asian Patients With Depressive Disorders: Findings From REAP-AD3
Seon-Cheol PARK ; Kiwon KIM ; Jeongsoo PARK ; Sun CHOI ; Seonhwa LEE ; Seungwon CHO ; Eunkyung KIM ; Tian-Mei SI ; Roy Abraham KALLIVAYALIL ; Andi J. TANRA ; Amir Hossein Jalali NADOUSHAN ; Kok Yoon CHEE ; Afzal JAVED ; Kang SIM ; Pornjira PARIWATCHARAKUL ; Takahiro A. KATO ; Shih-Ku LIN ; Naotaka SHINFUKU ; Norman SARTORIUS
Psychiatry Investigation 2025;22(5):552-563
Objective:
The clinical presentation of depressive disorders might be influenced by age, and its diagnosis and treatment can be affected by ageism-related bias. A network analysis can reveal symptom patterns unrecognized by the reductionistic approach. Therefore, this study explores the network structure of depression and anxiety symptoms in older Asian patients with depressive disorders and examines age-related differences in the context of ageism.
Methods:
We used data from the Research on Asian Psychotropic Prescription Patterns for Antidepressants, Phase 3 study and included 2,785 psychiatric patients from 11 Asian countries. Depression and anxiety symptoms were assessed using the Patient Health Questionnaire-9 and Generalized Anxiety Disorder-7. Network analyses were conducted to identify symptom interconnections and centrality among older (>65 years), middle-aged (35–64 years), and young (18–34 years) adult groups. The network structures were also compared using a network comparison test.
Results:
Depressed mood was the most central symptom across all age groups. Network comparisons revealed no significant structural differences among the three age groups, despite several variations in terms of global strength. The network structure of the older group was characterized by strong interconnections between somatic symptoms (insomnia-energy) and core depressive symptoms (little interest or pleasure-feelings of hopelessness).
Conclusion
This study reveals that the network structures of depression and anxiety symptoms have relatively consistent interconnections across age groups, despite subtle age-based differences. Specifically, older adults tend to present anxiety and depression symptoms as physical complaints. These findings challenge ageist stereotypes and advocate for inclusive, age-neutral approaches to treatment.
8.Poor Prognosis of Pneumococcal Co-Infection in Hospitalized Patients with COVID-19: A Propensity Score-Matched Analysis
Soyoon HWANG ; Eunkyung NAM ; Shin-Woo KIM ; Hyun-Ha CHANG ; Yoonjung KIM ; Sohyun BAE ; Nan Young LEE ; Yu Kyung KIM ; Ji Sun KIM ; Han Wook PARK ; Joon Gyu BAE ; Juhwan JEONG ; Ki Tae KWON
Infection and Chemotherapy 2025;57(1):172-178
The impact of Streptococcus pneumoniae coinfection on coronavirus disease 2019 (COVID-19) prognosis remains uncertain. We conducted a retrospective analysis of patients hospitalized with COVID-19 who underwent a pneumococcal urinary antigen (PUA) test to assess its clinical utility. Results showed that PUA-positive patients required more oxygen support, high-flow nasal cannula, and dexamethasone compared to PUA-negative patients.Furthermore, the significantly higher incidence of a National Early Warning Score ≥5 in the PUA-positive group (P<0.001) suggests that a positive PUA test is associated with a severe disease course. However, no significant difference in mortality was observed between the two groups, and antibiotics were used in almost all patients (96.2%). While the PUA test may help guide antibiotic use in COVID-19 patients, its interpretation should be approached with caution.
9.Poor Prognosis of Pneumococcal Co-Infection in Hospitalized Patients with COVID-19: A Propensity Score-Matched Analysis
Soyoon HWANG ; Eunkyung NAM ; Shin-Woo KIM ; Hyun-Ha CHANG ; Yoonjung KIM ; Sohyun BAE ; Nan Young LEE ; Yu Kyung KIM ; Ji Sun KIM ; Han Wook PARK ; Joon Gyu BAE ; Juhwan JEONG ; Ki Tae KWON
Infection and Chemotherapy 2025;57(1):172-178
The impact of Streptococcus pneumoniae coinfection on coronavirus disease 2019 (COVID-19) prognosis remains uncertain. We conducted a retrospective analysis of patients hospitalized with COVID-19 who underwent a pneumococcal urinary antigen (PUA) test to assess its clinical utility. Results showed that PUA-positive patients required more oxygen support, high-flow nasal cannula, and dexamethasone compared to PUA-negative patients.Furthermore, the significantly higher incidence of a National Early Warning Score ≥5 in the PUA-positive group (P<0.001) suggests that a positive PUA test is associated with a severe disease course. However, no significant difference in mortality was observed between the two groups, and antibiotics were used in almost all patients (96.2%). While the PUA test may help guide antibiotic use in COVID-19 patients, its interpretation should be approached with caution.
10.Comparison of Suicide Completion Rate in Korean Students Pre- and Post-COVID-19 Pandemics
Kyungjin LEE ; Boram NAM ; Kyoil SEO ; Eunkyung JO ; Seohyun KIM ; Deokyong SHIN ; Aeju KIM ; Youngil JEONG ; Yeni KIM
Psychiatry Investigation 2025;22(2):204-211
Objective:
This study compared the incidence of suicide cases among Korean students before and after the coronavirus disease-2019 (COVID-19) pandemic.
Methods:
Aggregated case reports of all known suicide victims attending elementary, middle, and high school in South Korea from 2017 to 2022 were analyzed. These reports, compiled by teachers under the directive of the South Korean Department of Education, surveyed the circumstances surrounding each suicide and identified associated risk factors posthumously.
Results:
The completed suicide rate was 2.37 per 100,000 students pre-COVID-19 (2017–2019), significantly increasing to 3.37 per 100,000 students post-COVID-19 (2020–2022; odds ratio [OR] 1.42, p<0.001). The rate began to rise approximately 6 months into the pandemic and continued to worsen throughout 2021 and 2022. Fair attendance significantly increased in 2020 (74.83%, p=0.003) during the initial stage of school closure measures compared to 2019 (58.27%) among students prior to suicide completion. However, as social distancing measures continued, “absence due to medical reasons” showed a significant increase in 2022 (23.56%) compared to 2019 (13.67%, p=0.025) and 2020 (9.52%, p<0.001) among these students. Among those who completed suicide, teachers reported increased signs of depression and anxiety posthumously compared to pre-COVID-19 periods.
Conclusion
The incidence of completed suicide among students was significantly higher in the post-COVID-19 years compared to pre-COVID-19. Attendance records and teachers’ reports indicated a deterioration in mental health among these students before suicide completion, highlighting the need to consider mental health impacts when implementing future quarantine policies.

Result Analysis
Print
Save
E-mail