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Porcine circovirus type 2 (PCV2) is an economically important swine pathogen that causes porcine circovirus-associated diseases (PCVADs). The objective of this study was to evaluate the use of specific pathogen-free Yucatan miniature pigs (YMPs) as an experimental model for PCV2d challenge and vaccine assessment because PCV2-negative pigs are extremely rare in conventional swine herds in Korea. In the first experiment, every three pigs were subjected to PCV2d field isolate or mock challenge. During three weeks of experiments, the PCV2d infection group exhibited clinical outcomes of PCVAD with high viral loads, lymphoid depletion, and detection of PCV2d antigens in lymphoid organs by immunohistochemistry. In the second experiment, three groups of pigs were challenged with PCV2d after immunization for three weeks: a nonvaccinated group (three pigs), a PCV2b-Vac group vaccinated with a commercial PCV2b-based inactivated vaccine SuiShot® Circo-ONE (five pigs), and a PCV2d-Vac group vaccinated with an experimental PCV2d-based inactivated vaccine (five pigs). During the three weeks of the challenge period, nonvaccinated pigs showed similar clinical outcomes to those observed in the PCV2d infection group from the first experiment. In contrast, both the PCV2b and PCV2d vaccinations produced good levels of protection against PCV2d challenge, as evidenced by reduced viral loads, improved growth performance, high virus-neutralizing antibody titers, and less development of PCV2-associated pathological lesions. Taken together, these data suggest that YMPs could be an alternative model for PCV2 challenge experiments, and these animals displayed typical clinical and pathological features and characteristics of protective immunity induced by the vaccines that were consistent with those resulting from PCV2 infections in conventional pigs. [ABSTRACT FROM AUTHOR]

Since the 2013–2014 incursion of the virulent G2b porcine epidemic diarrhoea virus (PEDV) pandemic strains in South Korea, frequent moderate‐scale regional outbreaks have recurred. In particular, areas of Jeju Island with extensive swine production have faced repeated epidemics since the re‐emergence in 2014. The current study reports the complete genome sequences and molecular characterization of the representative PEDV strains responsible for the 2018 endemic outbreaks on Jeju Island. All isolates were determined to belong genetically to the highly pathogenic pandemic G2b group. Full‐length genome sizes of four isolates differed from that of the G2b epidemic field strain due to insertion or deletion (DEL) mutations in the non‐structural protein (nsp)‐ or spike (S) protein‐coding regions. The 2018 Jeju isolates shared 96.7%–98.7% and 98.5%–99.4% identity at the S gene and whole‐genome levels, respectively, compared to global G2b PEDV strains. Genetic and phylogenetic analyses indicated that the 2018 isolates were closest to the 2014 G2b re‐emergent Jeju strains, but appeared to have undergone substantial rapid independent evolution. Among the isolates, a notable nsp3 DEL variant strain, KOR/KNU‐1807/2018, was isolated and propagated by continuous passages in Vero cells, and displayed typical PEDV‐induced syncytia formation. Genomic sequencing identified a unique 8‐nt DEL in the extreme C‐terminal region of the S gene at the 4th passage (KNU‐1807‐P4) compared to its original sample. This DEL resulted in the premature termination of S by nine amino acid residues (EVFEKVHVQ), which contained a KxHxx motif that is a potential endoplasmic reticulum retrieval signal. In vivo animal studies showed that variant strain KNU‐1807 had decreased virulence in suckling piglets. These results advance our knowledge regarding the genetic variation and pathogenicity of the G2b PEDV endemic strains prevalent in Jeju swine herds in South Korea. [ABSTRACT FROM AUTHOR]

Introduction: Post-resuscitation care of out-of-hospital cardiac arrest (OHCA) patients often involves inter-hospital transfer (IHT). We aimed to determine the association between IHT and outcomes of OHCA.Methods: This cross-sectional study used data from the nationwide emergency medical services (EMS)-based OHCA registry in Korea. All cases of adult patients with OHCA with a presumed cardiac aetiology and a sustained return of spontaneous circulation (ROSC) at hospitals between 2015 and 2016 were analysed. The primary outcome was a good neurological recovery at discharge, defined as cerebral performance in categories 1 or 2. We compared the primary outcome between a non-IHT group and an IHT group, using a propensity score-matching analysis. All analyses were performed separately by mean annual volume of patients with OHCA initially visiting high-volume emergency departments (HVEDs; >100 OCHA patients) and low-volume emergency departments (LVEDs; ≤100 OHCA patients).Results: Of 54,779 OHCA patients, 11,632 were included. Of 4477 patients who visited LVEDs initially, 1360 (30%) patients were transferred. Of 7155 patients who visited HVEDs initially, 604 (8%) patients were transferred. In the propensity score-matching analysis, the IHT group was more likely to have good neurological recovery than was the non-IHT group [adjusted odds ratio (OR): 1.34; 95% confidence interval (CI): 1.07-1.67] in LVED visitors, but there was no significant difference of good neurological recovery between the non-IHT group and the IHT group (adjusted OR: 0.84; 95% CI: 0.63-1.13) in HVED visitors.Conclusion: IHT should be considered when treating OHCA patients in LVEDs. [ABSTRACT FROM AUTHOR]

Background: Cold weather has been known to cause various cold-related local injuries as well as accidental hypothermia. Objectives: The aim of this study is to investigate the basal characteristics, outcomes, and risk factors of patients with cold-related comorbidities using prospective emergency department–based surveillance system in high-risk area. Methods: We designed a prospective emergency department–based surveillance system throughout northern part of Gyeonggi province located in the northernmost of South Korea. A total of 20 emergency departments participated in the surveillance system. Patients who visited emergency department with cold-related comorbidities from 1 December 2012 to 28 February 2013 were prospectively enrolled in final analysis. We analyzed risk factors associated with outcome and correlation between climate factor (wind-chill index) and incidence. Results: During the study period, 54 patients with cold-related comorbidities were used for final analysis, including 35 hypothermia, 15 frostbite, and 4 trench foot. Among 35 patients with accidental hypothermia, 11 patients were admitted to intensive care unit and defined to have major adverse outcome. Hypothermic patient with major adverse outcome had lesser possession of coat as outwear when exposed to the cold (9.1% vs 58.3%, p < 0.01). Lower wind-chill index was likely to develop higher incidence of cold-related comorbidities (incidence rate ratio per 1°C decrease in wind-chill index: 1.086 (95% confidence interval: 1.038–1.135)). Conclusion: Patients with cold-related comorbidities were successfully monitored with emergency department–based surveillance system. Absence of coat was associated with major adverse outcomes in patient with accidental hypothermia. Lower wind-chill index was associated with higher incidence of cold-related comorbidities. [ABSTRACT FROM AUTHOR]

The goal of this study was to investigate the association of prehospital oxygen administration flow with clinical outcome in severe traumatic brain injury (TBI) patients. This was a cross-sectional observational study using an emergency medical services-assessed severe trauma database in South Korea. The sample included adult patients with severe blunt TBI without hypoxia who were treated by EMS providers in 2013 and 2015. Main exposure was prehospital oxygen administration flow rate (no oxygen, low-flow 1~5, mid-flow 6~14, high-flow 15 L/min). Primary outcome was in-hospital mortality. A total of 1842 patients with severe TBI were included. The number of patients with no oxygen, low-flow oxygen, mid-flow oxygen, high-flow oxygen was 244, 573, 607, and 418, respectively. Mortality of each group was 34.8%, 32.3%, 39.9%, and 41.1%, respectively. Compared with the no-oxygen group, adjusted odds (95% CI) for mortality in the low-, mid-, and high-flow oxygen groups were 0.86 (0.62–1.20), 1.15 (0.83–1.60), and 1.21 (0.83–1.73), respectively. In the interaction analysis, low-flow oxygen showed lower mortality when prehospital saturation was 94–98% (adjusted odds ratio (AOR): 0.80 (0.67–0.95)) and ≥99% (AOR: 0.69 (0.53–0.91)). High-flow oxygen showed higher mortality when prehospital oxygen saturation was ≥99% (AOR: 1.33 (1.01~1.74)). Prehospital low-flow oxygen administration was associated with lower in-hospital mortality compared with the no-oxygen group. High-flow administration showed higher mortality. [ABSTRACT FROM AUTHOR]