Pasteurella Infections in South Korea and Systematic Review and Meta-analysis of Pasteurella Bacteremia.

Pasteurella spp. can cause fatal zoonotic infections in humans. We performed a multicenter study to investigate the prevalence and clinical features of Pasteurella infections in South Korea during 2018‒2022. We also conducted a collaborative systematic review and meta-analysis of the global burden of Pasteurella bacteremia. The study included 283 cases found an increasing trend in Pasteurella infections. Blood cultures were positive in 8/35 (22.9%) cases sampled, for overall bacteremia-associated rate of 2.8% (8/283). Aging was a significant risk factor for bacteremia (odds ratio 1.05 [95% CI 1.01-1.10]), according to multivariate analyses. For the meta-analysis, we included a total of 2,012 cases from 10 studies. The pooled prevalence of bacteremia was 12.4% (95% CI 7.3%-18.6%) and of mortality 8.4% (95% CI 2.7%-16.5%). Our findings reflect the need for greater understanding of the increase in Pasteurella infections and the global burden of Pasteurella bacteremia to determine appropriate case management.

Severe Human Parainfluenza Virus Community- and Healthcare-Acquired Pneumonia in Adults at Tertiary Hospital, Seoul, South Korea, 2010-2019.

The characteristics of severe human parainfluenza virus (HPIV)-associated pneumonia in adults have not been well evaluated. We investigated epidemiologic and clinical characteristics of 143 patients with severe HPIV-associated pneumonia during 2010-2019. HPIV was the most common cause (25.2%) of severe virus-associated hospital-acquired pneumonia and the third most common cause (15.7%) of severe virus-associated community-acquired pneumonia. Hematologic malignancy (35.0%), diabetes mellitus (23.8%), and structural lung disease (21.0%) were common underlying conditions. Co-infections occurred in 54.5% of patients admitted to an intensive care unit. The 90-day mortality rate for HPIV-associated pneumonia was comparable to that for severe influenza virus-associated pneumonia (55.2% vs. 48.4%; p = 0.22). Ribavirin treatment was not associated with lower mortality rates. Fungal co-infections were associated with 82.4% of deaths. Clinicians should consider the possibility of pathogenic co-infections in patients with HPIV-associated pneumonia. Contact precautions and environmental cleaning are crucial to prevent HPIV transmission in hospital settings.

Rare Case of Echinostoma cinetorchis Infection, South Korea.

A woman in South Korea who underwent a colonoscopy for occasional gastrointestinal discomfort had 4 adult flukes of Echinostoma cinetorchis showing 37 collar spines around the oral sucker recovered from the terminal ileum through the ascending colon. Partial gene sequencing showed high identity with E. cinetorchis.

Subdural Empyema from Streptococcus suis Infection, South Korea.

In Jeju Island, South Korea, a patient who consumed raw pig products had subdural empyema, which led to meningitis, sepsis, and status epilepticus. We identified Streptococcus suis from blood and the subdural empyema. This case illustrates the importance of considering dietary habits in similar clinical assessments to prevent misdiagnosis.

Medical Costs of Nontuberculous Mycobacterial Pulmonary Disease, South Korea, 2015-2019.

Nontuberculous mycobacterial pulmonary disease (NTM-PD) prevalence is a rising public health concern. We assessed the long-term healthcare systems perspective of costs incurred by 147 NTM-PD patients at a tertiary hospital in South Korea. Median cumulative total medical cost in managing NTM-PD patients was US $5,044 (interquartile range US $3,586-$9,680) over 49.7 months (interquartile range 33.0-68.2 months) of follow-up. The major cost drivers were diagnostic testing and medication, accounting for 59.6% of total costs. Higher costs were associated with hospitalization for Mycobacterium abscessus infection and pulmonary comorbidities. Of the total medical care costs, 50.2% were patient co-payments resulting from limited national health insurance coverage. As South Korea faces significant problems of poverty during old age and increasing NTM-PD prevalence, the financial and socio-economic burden of NTM-PD may become a major public health concern that should be considered with regard to adequate strategies for NTM-PD patients.

Concurrent Infection with Clade 2.3.4.4b Highly Pathogenic Avian Influenza H5N6 and H5N1 Viruses, South Korea, 2023.

Highly pathogenic avian influenza H5N6 and H5N1 viruses of clade 2.3.4.4b were simultaneously introduced into South Korea at the end of 2023. An outbreak at a broiler duck farm consisted of concurrent infection by both viruses. Sharing genetic information and international surveillance of such viruses in wild birds and poultry is critical.

Evolution and Spread of Highly Pathogenic Avian Influenza A(H5N1) Clade 2.3.4.4b Virus in Wild Birds, South Korea, 2022-2023.

During October 2022-March 2023, highly pathogenic avian influenza (HPAI) A(H5N1) clade 2.3.4.4b virus caused outbreaks in South Korea, including 174 cases in wild birds. To understand the origin and role of wild birds in the evolution and spread of HPAI viruses, we sequenced 113 HPAI isolates from wild birds and performed phylogenetic analysis. We identified 16 different genotypes, indicating extensive genetic reassortment with viruses in wild birds. Phylodynamic analysis showed that the viruses were most likely introduced to the southern Gyeonggi-do/northern Chungcheongnam-do area through whooper swans (Cygnus cygnus) and spread southward. Cross-species transmission occurred between various wild bird species, including waterfowl and raptors, resulting in the persistence of HPAI in wild bird populations and further geographic spread as these birds migrated throughout South Korea. Enhanced genomic surveillance was an integral part of the HPAI outbreak response, aiding in timely understanding of the origin, evolution, and spread of the virus.

Pathogenicity of Highly Pathogenic Avian Influenza A(H5N1) Viruses Isolated from Cats in Mice and Ferrets, South Korea, 2023.

The prevalence of highly pathogenic avian influenza (HPAI) A(H5N1) viruses has increased in wild birds and poultry worldwide, and concomitant outbreaks in mammals have occurred. During 2023, outbreaks of HPAI H5N1 virus infections were reported in cats in South Korea. The H5N1 clade 2.3.4.4b viruses isolated from 2 cats harbored mutations in the polymerase basic protein 2 gene encoding single amino acid substitutions E627K or D701N, which are associated with virus adaptation in mammals. Hence, we analyzed the pathogenicity and transmission of the cat-derived H5N1 viruses in other mammals. Both isolates caused fatal infections in mice and ferrets. We observed contact infections between ferrets, confirming the viruses had high pathogenicity and transmission in mammals. Most HPAI H5N1 virus infections in humans have occurred through direct contact with poultry or a contaminated environment. Therefore, One Health surveillance of mammals, wild birds, and poultry is needed to prevent potential zoonotic threats.

Trends in Nationally Notifiable Infectious Diseases in Humans and Animals during COVID-19 Pandemic, South Korea.

We investigated trends in notifiable infectious diseases in both humans and animals during the COVID-19 pandemic in South Korea and compared those data against expected trends had nonpharmaceutical interventions (NPIs) not been implemented. We found that human respiratory infectious diseases other than COVID-19 decreased by an average of 54.7% after NPIs were introduced. On the basis of that trend, we estimated that annual medical expenses associated with respiratory infections other than COVID-19 also decreased by 3.8% in 2020 and 18.9% in 2021. However, human gastrointestinal infectious diseases and livestock diseases exhibited similar or even higher incidence rates after NPIs were instituted. Our investigation revealed that the preventive effect of NPIs varied among diseases and that NPIs might have had limited effectiveness in reducing the spread of certain types of infectious diseases. These findings suggest the need for future, novel public health interventions to compensate for such limitations.

Identifying Contact Time Required for Secondary Transmission of Clostridioides difficile Infections by Using Real-Time Locating System.

Considering patient room shortages and prevalence of other communicable diseases, reassessing the isolation of patients with Clostridioides difficile infection (CDI) is imperative. We conducted a retrospective study to investigate the secondary CDI transmission rate in a hospital in South Korea, where patients with CDI were not isolated. Using data from a real-time locating system and electronic medical records, we investigated patients who had both direct and indirect contact with CDI index patients. The primary outcome was secondary CDI transmission, identified by whole-genome sequencing. Among 909 direct and 2,711 indirect contact cases, 2 instances of secondary transmission were observed (2 [0.05%] of 3,620 cases), 1 transmission via direct contact and 1 via environmental sources. A low level of direct contact (113 minutes) was required for secondary CDI transmission. Our findings support the adoption of exhaustive standard preventive measures, including environmental decontamination, rather than contact isolation of CDI patients in nonoutbreak settings.

A Prospective Sociocentric Study of 2 Entire Traditional Korean Villages: The Korean Social Life, Health, and Aging Project (KSHAP).

The Korean Social Life, Health, and Aging Project (KSHAP) was a multidisciplinary prospective study conducted in South Korea that measured various health biomarkers from blood, hair, and brain magnetic resonance imaging, and we examined their associations with sociocentric (global) social network data of older adults in 2 entire villages (or cohorts). Cohort K included participants aged 60 years or older, and cohort L included participants aged 65 years or older. We performed a baseline survey involving 814 of the 860 individuals (94.7% response rate) in cohort K in 2012 and 947 of the 1,043 individuals (90.8% response rate) in cohort L in 2017. We gathered longitudinal data for 5 waves in cohort K from 2011 to 2019 and 2 waves in cohort L from 2017 to 2022. Here, we describe for the first time the follow-up design of the KSHAP, the changes in social networks, and various biomarkers over a number of years. The data for cohort K are publicly available via the Korean Social Science Data Archive as well as the project website, and the data for cohort L will be shared soon.

The Impact of Minimum Wage Policy on Alcohol Use Disorder: A Quasi-Experimental Study in South Korea.

South Korea's 2018 minimum wage hike was examined for its impact on potential alcohol use disorders among affected individuals, using data from the Korea Welfare Panel Study (2015-2019). The study sample was restricted to workers aged 19-64 employed over the study years. The treatment group was identified as those below minimum wages, and the control group as those earning more than minimum wages in 2016-2017 (n=3,117 control, n=578 treatment). Using outcomes derived from the Alcohol Use Disorders Identification Test, our results from difference-in-differences models showed that the 2018 wage hike was linked to a 1.9% increase in the 'high risk' of alcohol use disorder and a 3.6% rise in hazardous consumption in the treatment group. Notably, the effects were more pronounced among men and those aged 50-64. Additionally, we confirmed that the spillover effects extended to workers earning up to 20% above the minimum wage. This study underscores the unintended substance use risk of minimum wage policies in the East Asian context. As wage policies are implemented, integrated public health campaigns targeting at-risk groups are required.

Suicide mortality following the implementation of tobacco packaging and pricing policies in Korea: an interrupted time-series analysis.

BACKGROUND: To prevent tobacco use in Korea, the national quitline number was added to tobacco packages in December 2012, tobacco prices were raised by 80% in January 2015, and graphic health warning labels were placed on tobacco packages in December 2016. This study evaluated the association of these tobacco packaging and pricing policies with suicide mortality in Korea. METHODS: Monthly mortality from suicide was obtained from Cause-of-Death Statistics in Korea from December 2007 to December 2019. Interrupted time-series analysis was performed using segmented Poisson regression models. Relative risks (RRs) and 95% confidence intervals (CIs) were calculated adjusted for suicide prevention strategies. RESULTS: Suicide mortality was 20 per 1,000,000 in December 2007 and showed a downward trend over the study period. After the implementation of tobacco packaging and pricing policies, suicide mortality immediately declined by - 0.09 percent points (95% CI = - 0.19 to 0.01; P > 0.05) for the national quitline number, - 0.22 percent points (95% CI = - 0.35 to - 0.09; P < 0.01) for tobacco prices, and - 0.30 percent points (95% CI = - 0.49 to - 0.11; P < 0.01) for graphic health warning labels. The corresponding RRs for these post-implementation changes compared with the pre-implementation level were 0.91 (95% CI = 0.83 to 1.00), 0.80 (95% CI = 0.70 to 0.91), and 0.74 (95% CI = 0.61 to 0.90), respectively. Significant associations between tobacco control policies and suicide mortality were observed even when stratified by sex and region. CONCLUSIONS: The findings of this study provide new evidence for an association between tobacco control policies and deaths by suicide. An array of effective tobacco control policies should be considered for prevention programs targeting suicide.

Continental scale comparison of mycobiomes in Parmelia and Peltigera lichens from Turkey and South Korea.

BACKGROUND: Lichens, traditionally considered as a simple partnership primarily between mycobiont and photobiont, are, in reality, complex holobionts comprised of a multitude of microorganisms. Lichen mycobiome represents fungal community residing within lichen thalli. While it is acknowledged that factors like the host lichen species and environmental conditions influence the structure of the lichen mycobiome, the existing research remains insufficient. To investigate which factor, host genus or location, has a greater impact on the lichen mycobiome, we conducted a comparative analysis of mycobiomes within Parmelia and Peltigera collected from both Turkey and South Korea, using high-throughput sequencing based on internal transcribed spacer region amplification. RESULTS: Overall, the lichen mycobiome was dominated by Capnodiales (Dothideomycetes), regardless of host or location. At the order level, the taxonomic composition was not significantly different according to lichen genus host or geographical distance. Hierarchical clustering of the top 100 abundant ASVs did not clearly indicate whether the lichen mycobiome was more influenced by host genus or location. Analyses of community similarity and partitioning variables revealed that the structure of the lichen mycobiome is more significantly influenced by location than by host genus. When analyzing the core mycobiome by host genus, the Peltigera mycobiome contained more ASV members than the Parmelia mycobiome. These two core mycobiomes also share common fungal strains, including basidiomycete yeast. Additionally, we used chi-squared tests to identify host genus-specialists and location-specialists. CONCLUSIONS: By comparing lichen mycobiomes of the same genera across different countries, our study advances our comprehension of these microbial communities. Our study elucidates that, although host species play a contributory role, geographic distance exerts a more pronounced impact on the structure of lichen mycobiome. We have made foundational contributions to understanding the lichen mycobiome occupying ecologically crucial niches. We anticipate that broader global-scale investigations into the fungal community structures will provide more detailed insights into fungal residents within lichens.

Identification of a novel orthonairovirus from ticks and serological survey in animals near China-North korea border.

Emerging pathogenic tick-borne viruses (TBVs) have attracted a great deal of attention due to their significant impact on human and animal health. A novel orthonairovirus named Dadong virus (DDV) was isolated from Haemaphysalis concinna ticks in the Changbai Mountain region on the China-North Korea border. DDV can induce cytopathic effects in mammalian and human cell lines. Phylogenetic analysis showed that it belongs to the genus Orthonairovirus, family Nairoviridae, exhibiting 72.4%-81.3% nucleic acid identity to Tofla orthonairovirus, known to cause lethal infection in IFNAR KO mice. The first serological evidence of DDV circulating in cattle and mice was also obtained, with 4.0% (1/25) of cattle and 2.27% (1/44) of mice seropositive for DDV. Further investigations, including serological surveys using human samples, are required to assess the public health risk posed by DDV.

Association between Pentosan Polysulfate and Subsequent Maculopathy: Insights from a Nationwide Population-Based Study in Korea.

PURPOSE: To determine the association between pentosan polysulfate (PPS) use and the subsequent development of maculopathy in Asian population. DESIGN: A nationwide population-based retrospective cohort study using the Health Insurance Review and Assessment Service database. PARTICIPANTS: 103,553 individuals in the PPS user group and 205,792 individuals in the PPS non-user group, all newly diagnosed with cystitis between 2009 and 2020. METHODS: The association between PPS use and maculopathy was evaluated using a time dependent Cox proportional hazard model. Additionally, two sensitivity analyses were conducted by defining PPS users as individuals with an observation period over 6 months from the initial prescription or those with cumulative dose exceeding 9 g, employing the same analysis. MAIN OUTCOME MEASURES: The outcome measures included the hazard ratios (HR) representing the association between PPS use and maculopathy. RESULTS: PPS use was associated with an increased risk of subsequent maculopathy in univariate (HR, 1.7; 95% confidence intervals [CI], 1.66-1.75) and multivariate analysis (HR, 1.34; 95% CI, 1.31-1.38). These results were also confirmed in two sensitivity analyses. The mean cumulative dose of PPS for the cohort was 37.2 ± 76.7 g. CONCLUSIONS: In this nationwide cohort study involving an Asian population, individuals with cystitis using PPS exhibit an increased risk of developing subsequent maculopathy.

Association of Soda Drinks and Fast Food with Allergic Diseases in Korean Adolescents: A Nationwide Representative Study.

INTRODUCTION: A high consumption of carbonated soft drinks (i.e., soda drinks) and fast food is potentially associated with the observed global rise in adolescent allergic diseases. Thus, our study aimed to examine the potential associations between the consumption of soda drinks and fast food and allergic conditions, identifying specific relationships across subgroups and each allergic condition (asthma, allergic rhinitis, and atopic dermatitis). METHODS: This study uses large-scale data from the Korea Youth Risk Behavior Web-Based Survey (total n = 865,614). Soda drinks and fast food were defined by a self-reported questionnaire and allergic conditions by physician-diagnosed within 1 year. Multivariable logistic regression was used to analyze the weighted odds ratios (ORs), along with 95% confidence intervals (CIs), for allergic diseases associated with the intake of soda drinks and fast food. RESULTS: Among 865,614 adolescents in grades 7-12 (male, 51.40%), patients with asthma, allergic rhinitis, and atopic dermatitis were 18,568 (2.15%), 153,536 (17.74%), and 59,014 (6.82%), respectively. Current asthma was associated with soda drinks (OR, 1.07; 95% CI, 1.03-1.12) and fast food consumption (1.25; 1.17-1.33). Interestingly, stronger associations were observed for female high schoolers, compared to male high schoolers and middle schoolers, in relation to the consumption of soda drinks (1.31; 1.19-1.44) and fast food (1.46; 1.26-1.69) with asthma. Current allergic rhinitis and atopic dermatitis had no significant association with fast food consumption and soda drinks. CONCLUSION: This first large-scale study suggests that fast food and soda drinks consumption are potentially associated with current asthma, with stronger associations observed in females than males, underscoring the need for sex-specific allergy prevention programs.

Sex-Specific and Long-Term Trends of Asthma, Allergic Rhinitis, and Atopic Dermatitis in South Korea, 2007-2022: A Nationwide Representative Study.

INTRODUCTION: Although sex differences in allergic diseases such as atopic dermatitis (AD), allergic rhinitis (AR), and asthma are considered important, a limited number of studies during the COVID-19 pandemic investigated this aspect. Therefore, this study aimed to analyze sex-specific and long-term trends and risk factors for allergic diseases before and during the pandemic. METHODS: This study utilized data from the Korea National Health and Nutrition Examination Survey, 2007-2022, including 92,135 participants aged 19 years and older. This study used weighted multivariate regression analysis to examine the estimates of related factors and assessed weighted odds ratios or ß-coefficients for these factors across multiple categories. RESULTS: During the study period (2007-2022), the prevalence of AR was more common in females than in males. Particularly in 2022, the prevalence among females was 19.3% (95% confidence interval, 17.3-21.3), while among males, it was 15.6% (13.8-17.4). The prevalence of AD and asthma showed a slight disparity between males and females. Before and during the pandemic, the prevalence of AD and AR showed a continuous increase (AD: from 2.8% [2.5-3.2] in 2007-2009 to 4.7% [3.9-5.4] in 2022; AR: from 11.7% [11.1-12.4] in 2007-2009 to 17.4% [16.0-18.9] in 2022), while asthma maintained a relatively stable trend. Moreover, this study identified several sex-specific factors that seem to be associated with a higher prevalence of allergic diseases in females, such as high household income, smoking, and being overweight or obese. CONCLUSIONS: Throughout all the periods examined, females consistently exhibited a higher prevalence of AR compared to males. Moreover, the risk factors for males and females varied depending on the disease, with females generally facing a greater number of risk factors. Consequently, this study highlights the necessity for sex-specific health interventions and further research to comprehend the complex influence of socioeconomic factors and lifestyle choices on the prevalence and risk of AD, AR, and asthma.

National Trends and Prevalence of Atopic Dermatitis and Pandemic-Related Factors among Korean Adults, 2007-2021.

INTRODUCTION: Previous studies have variably reported inconclusive trends in the prevalence of atopic dermatitis (AD) among adults, and there are limited data on the impact of the COVID-19 pandemic. We aimed to investigate the national trends and age-stratified prevalence of AD among adults from 2007 to 2021 in South Korea, focusing mainly on the impact of the COVID-19 pandemic-related factors. METHODS: A nationwide cross-sectional study was conducted using the Korea National Health and Nutrition Examination Survey data from 2007 to 2021. Overall and age-stratified prevalence for AD were assessed using weighted beta coefficients or odds ratios. RESULTS: A total of 83,566 adults over 20 years (male, 49.40%) were included. During the observation period, the prevalence of AD was stable in the overall population from 2.61% (95% CI, 2.29-2.93) in 2007-2009 to 2.15% (1.68-2.63) in 2020 and 2.38% (1.81-2.95) in 2021. However, the weighted prevalence of AD in adults aged 40-59 years old decreased during the pre-pandemic era, and the prevalence of AD in adults aged above 60 years significantly decreased during the pandemic, with a significant decline observed after the initial outbreak. From age-stratification analysis, the adults aged 40-59 years showed a significant increase after the pandemic outbreak which was evident in specific variables: individuals with rural residence, lower education, and lower household income quartiles. Adults aged above 60 years showed a significant decrease in the slope after the outbreak, evident in specific variables: individuals of female, rural residence, lower education, and lower household income quartiles. CONCLUSION: We observed a stable overall prevalence of AD throughout the 15-year observation period. However, the age-stratified analysis suggested significantly different trends according to age-stratified groups and the impact of the COVID-19 pandemic on the prevalence of AD.

Cumulative effect of unemployment on suicide mortality in South Korean workers (2018-2019).

BACKGROUND: While unemployment is known to increase the risk of suicide, its cumulative effect remains underexplored. This study investigates how unemployment affects suicide mortality and whether the effect varies based on the number of unemployment spells using two years of nationwide data. METHODS: Using the data from the National Statistical Office and Employment Insurance Database for 2018 and 2019, we identified an average of 2365 cases of suicide over two years among 7.76 million workers aged 25-64 years who had been employed within one year before their suicide. The number of unemployment spells was counted using the employment history of the past five years. We calculated crude suicide mortality rates per 100 000 population, age- and sex- standardized mortality rates (SMRs), and proportionate mortality rates (PMRs) for suicide. RESULTS: Over the two years, the crude suicide rate was 30.0 per 100 000 among the general population and 30.5 among workers. Workers with no unemployment spells in the past five years had a significantly lower SMR (0.44; 0.42-0.46), while those with four or more unemployment spells had a significantly higher SMR (3.13; 2.92-3.35) than the general population. These findings were consistent across all sex and age groups. Additionally, workers with four or more unemployment spells had a significantly higher PMR than the general population. CONCLUSION: The impact of unemployment on suicide mortality intensifies as the number of unemployment spells increases. These results underscore the necessity for additional social and psychological support along with economic assistance for individuals facing recurrent unemployment.