Background: Pathogenic Escherichia coli (PEC) is a leading cause of acute diarrhea worldwide. With increasing antibiotic use, antimicrobial resistance in PEC has become a significant public health concern. In this study, we investigated the distribution and antimicrobial susceptibility patterns of PEC isolated from patients with acute diarrhea in the Busan and Gyeongnam regions of South Korea. Methods: In this retrospective cross-sectional laboratory-based study, 272 PCR-positive residual stool or rectal swab specimens collected between October 2023 and June 2024 were screened; after exclusion of 80 specimens without recoverable or confirmable isolates, 192 pathogenic E. coli isolates were included for pathotype identification and antimicrobial susceptibility testing. Pathotypes were identified using multiplex real-time polymerase chain reaction, and antimicrobial susceptibility was tested against 18 agents using the VITEK II system. Results: Enteroaggregative E. coli (EAEC) was the most prevalent pathotype (44.8%), followed by enteropathogenic E. coli (34.9%). High resistance rates were observed for ampicillin (77.1%), cefazolin (55.2%), and amoxicillin/clavulanic acid (44.3%). EAEC demonstrated the highest multidrug resistance (MDR) rate (34.9%). Pediatric patients (< 18 years) exhibited significantly higher resistance rates and MDR frequencies compared with adults, particularly against β-lactam antibiotics. Conclusion EAEC was identified as the predominant and most resistant pathotype in this region. The elevated resistance levels in children and the prevalence of MDR EAEC underscore the need for continuous local surveillance and appropriate antibiotic stewardship.

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.

Background: We aimed to analyze the risk factors for sudden death after diagnosis of coronavirus disease 2019 (COVID-19) in South Korea and to provide evidence for informing prevention and control interventions for patients at risk of sudden death. Methods: We included 30,302 COVID-19 related deaths registered in the patient management information system (Central Disease Control Headquarters) between January 1, 2021, and December 15, 2022. We collected their epidemiological data recorded by the reporting city, province, or country. We performed multivariate logistic regression analysis to identify risk factors for sudden death after diagnosis of COVID-19. Results: Among the 30,302 deaths, there were 7,258 (24.0%) and 23,044 (76.0%) sudden and non-sudden deaths, respectively. Sudden death means a person who died within 2 days of diagnosis and who did not receive inpatient treatment. Underlying condition, vaccination status, and place of death were significantly associated with the survival period in all age groups. Moreover, region, sex, and prescription were significantly associated with the survival period only in certain age groups. However, reinfection was not significantly associated with the survival period in any age group. Conclusion To our knowledge, this is the first study on the risk factors for sudden death after a diagnosis of COVID-19, which included age, underlying condition, vaccination status, and place of death. Additionally, individuals aged < 60 years without an underlying condition were at high risk for sudden death. However, this group has relatively low interest in health, as can be seen from the high non-vaccination rate (16.1% of the general population vs. 61.6% of the corresponding group). Therefore, there is a possibility for the presence of an uncontrolled underlying disease in this population. In addition, many sudden deaths occurred due to delayed hospital visits to continue economic activities even after the onset of COVID-19 symptoms (7 days overall vs. 10 days average for the group). In conclusion, ‘continued interest in health’ is a key factor in avoiding sudden death in the economically active group (under 60 years of age).

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.