Objective: We investigated the distribution of AI viruses in fecal samples from wild bird habitats (and nearby poultry-farm areas) surveyed between September and March from 2019 to 2025 and identified associated epidemiological risk factors. Methods: Samples were screened for influenza A (M, H5, H7) genes using real-time reverse transcription polymerase chain reaction (PCR), subjected to virus isolation in embryonated chicken eggs, and subtyped by PCR and sequencing. Host species were identified through DNA barcoding. Relative risks (RRs) with 95% confidence intervals were estimated for province, month, and waterfowl density. Results: Overall prevalence of HPAI and low pathogenic AI (LPAI) virus was 0.10% and 3.21%, respectively. HPAI virus was continuously isolated since 2020–2021, except 2019– 2020, while LPAI prevalence steadily increased (3.01%–4.35%). Twelve hemagglutinin (H1–H12) subtypes were identified in 1,722 isolates, and H3 (16.5%) was the most prevalent, followed by H5 (11.1%) and H7 (5.2%). LPAI H5N3 (55.7%) and H7N7 (75.5%) were the predominant H5 and H7 subtypes, respectively. Detection was higher in western coastal provinces, and higher mallard/spot-billed duck density and sampling in September– December were associated with increased risk. Conclusions and Relevance: Continued surveillance of migratory-bird habitats can provide early warning of HPAIV incursions and support targeted biosecurity measures in high-risk regions and seasons.

Purpose: Esophagojejunostomy leakage (EJL) remains one of the most critical complications following total gastrectomy for gastric cancer. This study aimed to evaluate the evolving therapeutic approaches and clinical outcomes of EJL using data from a large-scale multicenter retrospective cohort. Methods: Among 6,577 patients who underwent total gastrectomy or proximal gastrectomy with double tract reconstruction at nine institutions from 2003 to 2024, 196 (3.0%) developed EJL. Of these, 162 patients with comprehensive clinical data were included in the final analysis. The study examined treatment modalities, changes in management over time, patient characteristics, surgical variables, and clinical outcomes. Four groups were defined according to treatment approach: conservative, endoscopic, reoperation, and multimodal (combined) therapy. Results: Endoscopic therapy was first introduced in 2011 and has progressively supplanted reoperation, now comprising 32.5% of cases. The average time to EJL diagnosis was 8.4 days after surgery. Overall in-hospital mortality was 6.1% (10/162). When conservative management was excluded, endoscopic treatment demonstrated the highest rate of therapeutic success (94.3%, p = 0.004). Both the duration until diet resumption and length of hospital stay were notably reduced in the endoscopic and conservative groups compared with reoperation and multimodal therapy (p < 0.001). Moreover, although the highest post-leakage hospitalization costs were observed with multimodal treatment (p < 0.001), overall hospitalization expenses were significantly lower for patients managed conservatively or with endoscopic intervention (p < 0.001). Conclusion Over the past two decades, management of EJL has shifted toward endoscopic approaches. Endoscopic therapies yield superior clinical outcomes and should be considered a primary option for appropriate candidates.

As of September 3, 2022, 5,388,338 coronavirus disease 2019 (COVID-19) cases and 46 deaths (3 in 2021 and 43 in 2022) were reported in children ≤ 18 years in Korea. Cumulative confirmed cases accounted for 67.3% of the population aged ≤ 18 years and case fatality rate was 0.85/100,000. Among 46 fatal cases, 58.7% were male and median age was 7 years.Underlying diseases were present in 47.8%; neurologic diseases (63.6%) and malignancy (13.6%) most common. Only four had history of COVID-19 immunization. COVID-19 associated deaths occurred at median 2 days from diagnosis (range: −1 to 21). Among COVID-19 deaths, 41.3% occurred before admission; 2 before hospital arrival and 17 in the emergency department. Among children whose cause was documented, myocarditis, respiratory and multiorgan failure were most common. COVID-19 associated death was seen early after diagnosis in children and public health policies to provide access to medical care for children with COVID-19 are essential during the pandemic.

Objectives: This study aimed to classify coronavirus disease 2019 (COVID-19)-related deaths according to whether COVID-19 was listed as the cause of death, and to investigate thedifferences in demographic characteristics and risk factors for COVID-19 death classifications. Methods: A total of 5,625 deaths in South Korea among patients with confirmed COVID-19 from January 20, 2020 to December 31, 2021 were selected. Excluding false reports and unnatural deaths, 5,597 deaths were analyzed. Based on death report data, deaths were classified according to whether the cause of death was listed as COVID-19 (CD) or not (NCD). The epidemiological characteristics and causes of deaths were investigated using descriptive, univariate, and multivariate statistical analyses. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated to analyze the risk factors. Results: The case fatality ratio was 0.89% and increased with age. Additionally, 96.4% of the subjects had an underlying disease, and 53.4% died in winter. The proportion of NCDs was 9.3%, of whom 19.1% died at home and 39.0% were confirmed to have COVID-19 after death. Malignant neoplasms (102/416 vs. 637/4,442; OR, 1.71; 95% CI, 1.36−2.16; p < 0.001) were significantly associated with NCD. Conclusion This is the first study to analyze risk factors by cause of death using COVID-19death report data in South Korea. These results are expected to be used as evidence forestablishing a death monitoring system that can collect timely information in a new infectiousdisease pandemic.

Background/Aims: We evaluated the feasibility and long-term efficacy of the combination of cytarabine, idarubicin, and all-trans retinoic acid (ATRA) for treating patients with newly diagnosed acute promyelocytic leukemia (APL). Methods: We included 87 patients with newly diagnosed acute myeloid leukemia and a t(15;17) or promyelocytic leukemia/retinoic acid receptor alpha (PML-RARα) mutation. Patients received 12 mg/m2/day idarubicin intravenously for 3 days and 100 mg/m2/day cytarabine for 7 days, plus 45 mg/m2/day ATRA. Clinical outcomes included complete remission (CR), relapse-free survival (RFS), overall survival (OS), and the secondary malignancy incidence during a 20-year follow-up. Results: The CR, 10-year RFS, and 10-year OS rates were 89.7%, 94.1%, and 73.8%, respectively, for all patients. The 10-year OS rate was 100% for patients that achieved CR. Subjects were classified according to the white blood cell (WBC) count in peripheral blood at diagnosis (low-risk, WBC < 10,000/mm3; high-risk, WBC ≥ 10,000/mm3). The low-risk group had significantly higher RFS and OS rates than the high-risk group, but the outcomes were not superior to the current standard treatment (arsenic trioxide plus ATRA). Toxicities were similar to those observed with anthracycline plus ATRA, and higher than those observed with arsenic trioxide plus ATRA. The secondary malignancy incidence after APL treatment was 2.7%, among the 75 patients that achieved CR, and 5.0% among the 40 patients that survived more than 5 years after the APL diagnosis. Conclusions Adding cytarabine to anthracycline plus ATRA was not inferior to anthracycline plus ATRA alone, but it was not comparable to arsenic trioxide plus ATRA. The probability of secondary malignancy was low.

Objectives: This study was carried out to understand the seroprevalence and risk factors for severe fever with thrombocytopenia syndrome (SFTS) among the Korea National Park Service (KNPS) workers. Methods: We used the stored serum samples (763) and survey results collected from the previous investigation on scrub typhus and Lyme disease among the KNPS workers during 2016-2017. The serum samples were analyzed by double-antigen sandwich enzyme-linked immunosorbent assay, which was used to test the total antibody including IgG and IgM. Results: The SFTS seroprevalence among the KNPS worrkers was 1.4%. In multivariate logistic analysis, the national park exploration programs (odds ratio, 3.48; 95% confidence interval, 1.01-12.01) was significantly associated with the seroprevalence of SFTS. Conclusion This study was the first serological study of SFTS among forestry workers in South Korea. Although the KNPS workers are at a high-risk group of SFTS, the prevention activities related to the working environment and habit was insufficient. Thus, systematic prevention education and training for the KNPS workers need to be strengthened.

Background/Aims: Hepatocellular carcinoma (HCC) is the sixth most common cancer and the second leading cause of cancer-related death in Korea. This study evaluated the characteristics of Korean patients newly diagnosed with HCC in 2015. Methods: Data from the Korean Primary Liver Cancer Registry (KPLCR), a representative sample of patients newly diagnosed with HCC in Korea, were analyzed. A total of 1,558 patients with HCC registered in the KPLCR in 2015 were investigated. Results: The median age was 61.0 years (interquartile range, 54.0-70.0 years), and men accounted for 79.7% of the subjects. Hepatitis B virus infection was the most common underlying liver disease (58.1%). According to the Barcelona Clinic Liver Cancer (BCLC) staging system, stage 0, A, B, C, and D HCCs accounted for 14.2%, 26.3%, 12.7%, 39.0%, and 7.8% of patients, respectively. Transarterial therapy (29.5%) was the most commonly performed initial treatment, followed by surgical resection (25.1%), best supportive care (20.2%), and local ablation therapy (10.5%). Overall, 42.4% of patients were treated in accordance with the BCLC guidelines: 61.7% in stage 0/A, 39.0% in stage B, 18.1% in stage C, and 71.6% in stage D. The 1-, 3-, and 5-year OS rates were 66.5%, 49.0%, and 17.0%, respectively. Conclusions In 2015, approximately 40% of Korean HCC cases were diagnosed at a very early or early stage, and 35% of patients underwent potentially curative initial treatment. BCLC guidance was followed in 42.4% of patients; in patients with stage B or C disease, there was relatively low adherence.

Background/Aims: Hepatocellular carcinoma (HCC) is the sixth most common cancer and the second leading cause of cancer-related death in Korea. This study evaluated the characteristics of Korean patients newly diagnosed with HCC in 2015. Methods: Data from the Korean Primary Liver Cancer Registry (KPLCR), a representative sample of patients newly diagnosed with HCC in Korea, were analyzed. A total of 1,558 patients with HCC registered in the KPLCR in 2015 were investigated. Results: The median age was 61.0 years (interquartile range, 54.0-70.0 years), and men accounted for 79.7% of the subjects. Hepatitis B virus infection was the most common underlying liver disease (58.1%). According to the Barcelona Clinic Liver Cancer (BCLC) staging system, stage 0, A, B, C, and D HCCs accounted for 14.2%, 26.3%, 12.7%, 39.0%, and 7.8% of patients, respectively. Transarterial therapy (29.5%) was the most commonly performed initial treatment, followed by surgical resection (25.1%), best supportive care (20.2%), and local ablation therapy (10.5%). Overall, 42.4% of patients were treated in accordance with the BCLC guidelines: 61.7% in stage 0/A, 39.0% in stage B, 18.1% in stage C, and 71.6% in stage D. The 1-, 3-, and 5-year OS rates were 66.5%, 49.0%, and 17.0%, respectively. Conclusions In 2015, approximately 40% of Korean HCC cases were diagnosed at a very early or early stage, and 35% of patients underwent potentially curative initial treatment. BCLC guidance was followed in 42.4% of patients; in patients with stage B or C disease, there was relatively low adherence.

Objective: To examine the concordance between the oropharyngeal flora and peristomal wound culture bacteria following percutaneous endoscopic gastrostomy (PEG) placement. Methods: Cultures of oropharyngeal flora before PEG placement and peristomal wound cultures after PEG placement were examined prospectively in patients who underwent PEG between June 1, 2017, and June 1, 2019, at a local rehabilitation center. Microorganisms in the oropharyngeal flora and peristomal wound culture were identified, and the relationship between them was examined. The risk factors that may increase the PEG infection rate were also examined. Results: The predominant bacterium identified in the oropharyngeal flora and peristomal wounds in patients who required PEG was Pseudomonas aeruginosa. The concordance between the oropharyngeal flora and peristomal wound culture bacteria in patients with PEG infections was confirmed. Different oropharyngeal flora was observed in patients with a prolonged hospital stay compared to that of healthy adults. The concordance between the oropharyngeal flora and peristomal wounds was also identified with a high prevalence of gram-negative bacilli. There was no potential risk factor, such as comorbidities or length of hospitalization of patients associated with PEG infections. Conclusion Because the oropharyngeal flora showed concordance with the bacteria found in the PEG stoma site, management of the oropharyngeal flora before PEG insertion should be considered for patients with dysphagia.

PURPOSE: To compare the results of two different instruments made of stainless steel and titanium alloy for correction of single thoracic adolescent idiopathic scoliosis (AIS) using pedicle screw instrumentation. MATERIALS AND METHODS: A total of 141 patients with single thoracic AIS treated with pedicle screw instrumentation and selective thoracic fusion were retrospectively reviewed after a follow-up of 2 years. The patients had a main thoracic curve of 40° to 75° and were divided into two groups based on instrument materials; S group (stainless steel, n=90) and T group (titanium alloy, n=51). The diameter of the stainless steel rod used was 7.0 mm while that of the titanium alloy rod was 6.35 mm or 6.0 mm. Standing long-cassette radiographic measurements including various coronal and sagittal parameters for the preoperative, early postoperative and 2-year postoperative follow-up were analyzed. There were no significant differences in the preoperative curve characteristics between the two groups. RESULTS: In the S group, the preoperative main thoracic curve of 51.3°±8.4° was improved to 19.0°±7.6° (63.1% correction) and the lumbar curve of 32.3°±8.4° spontaneously decreased to 12.7°±8.2° (62.9% correction) at 2 years postoperatively. In the T group, the preoperative main thoracic curve of 49.5°±8.4° and the lumbar curve of 30.3°±8.9° was improved to 18.8°±7.4° (62.2% correction) and 11.3°±5.4° (63.3% correction), respectively. The corrections of coronal curves were not statistically different between the two groups (p>0.05). The thoracic kyphosis was changed from 16.8°±8.5° to 24.3°±6.1° in the S group and from 19.6°±11.2° to 26.6°±8.5° in the T group. There were no significant differences in the changes of sagittal curves, coronal and sagittal balances at the 2-year follow-up and the number of fused segments and used screws between the two groups (p>0.05). CONCLUSION: When conducting surgery for single thoracic AIS using pedicles screw instrumentation, two different instruments made of stainless steel and titanium alloy showed similar corrections for coronal and sagittal curves.
Adolescent ; Alloys ; Follow-Up Studies ; Humans ; Kyphosis ; Pedicle Screws ; Retrospective Studies ; Scoliosis ; Stainless Steel ; Steel ; Titanium