Novel recombinant avian infectious bronchitis viruses from chickens in Korea, 2019-2021.

Infectious bronchitis virus (IBV) has evolved through various mutation mechanisms, including antigenic drift and recombination. Four genotypic lineages of IBVs including GI-15, GI-16, GI-19, and GVI-1 have been reported in Korea. In this study, we isolated two IBVs from chicken farms, designated IBV/Korea/289/2019 (K289/19) and IBV/Korea/163/2021 (K163/21), which are two distinct natural recombinant viruses most likely produced by genetic reassortment between the S1 gene of K40/09 strain (GI-19 lineage) and IBV/Korea/48/2020 (GI-15 lineage) in co-infected commercial chickens. Comparative sequence analysis of hypervariable regions (HVRs) revealed that the K289/19 virus had similar HVR I and II with the K40/09 virus (100% and 99.2% nucleotide sequence identity, respectively), and HVR III with the IBV/Korea/48/2020 virus (100% nucleotide sequence identity). In contrast, the K163/21 virus had HVR I and II similar to the IBV/Korea/48/2020 virus (99.1% and 99.3% nucleotide sequence identity, respectively), and HVR III to the K40/09 virus (96.6% nucleotide sequence identity). The K289/19 virus exhibited similar histopathologic lesions, tissue tropism in trachea and kidney, and antigenicity with the parental K40/09 virus. The K163/21 exhibited similar pathogenicity and tissue tropism with the K40/09 virus, which were similar results with the isolate K289/19. However, it showed a lower antigenic relatedness with both parental strains, exhibiting R-value of 25 and 42, respectively. The continued emergence of the novel reassortant IBVs suggests that multiple recombination events have occurred between different genotypes within Korea. These results suggest that antigenic profiles could be altered through natural recombination in the field, complicating the antigenic match of vaccine strains to field strains. Enhanced surveillance and research into the characteristics of newly emerging IBVs should be carried out to establish effective countermeasures.

Validation of the Dimensions of Anger Reactions Scale (the DAR-5) in non-clinical South Korean adults.

BACKGROUND: Posttraumatic anger is a commonly reported emotion among people who have experienced traumatic events. The current study aimed to demonstrate the reliability and validity of the South Korean version of the DAR-5 (DAR-5-K). The DAR-5 is a single scale with 5 items which measures posttraumatic anger. The DAR-5 is composed of five items that measure anger frequency, intensity, duration, aggression, and its interference with social relations. METHODS: Data were collected from 814 South Korean adults who had experienced traumatic events and participated in the study and analyzed via the combination of exploratory factor analysis (n = 405) and confirmatory factor analysis (n = 409). RESULTS: Results supported the one-factor structure, as reported in previous validation studies. The scale demonstrated robust internal reliability and concurrent validity with measures of posttraumatic stress disorder (PTSD) symptoms, depression, anxiety, and self-esteem. The DAR-5 cut-off score of 12 that was established in the original validation study successfully differentiated high from low scorers with regard to PTSD symptoms, depression, anxiety, and self-esteem. CONCLUSION: The results confirm that the DAR-5-K is a brief and psychometrically robust measure of anger that can be used to examine South Korean adults who have experienced traumatic events.

Investigation of cross-regional spread and evolution of equine influenza H3N8 at US and global scales using Bayesian phylogeography based on balanced subsampling.

Equine influenza virus (EIV) is a highly contagious pathogen of equids, and a well-known burden in global equine health. EIV H3N8 variants seasonally emerged and resulted in EIV outbreaks in the United States and worldwide. The present study evaluated the pattern of cross-regional EIV H3N8 spread and evolutionary characteristics at US and global scales using Bayesian phylogeography with balanced subsampling based on regional horse population size. A total of 297 haemagglutinin (HA) sequences of global EIV H3N8 were collected from 1963 to 2019 and subsampled to global subset (n = 67), raw US sequences (n = 100) and US subset (n = 44) datasets. Discrete trait phylogeography analysis was used to estimate the transmission history of EIV using four global and US genome datasets. The North American lineage was the major source of globally dominant EIV variants and spread to other global regions. The US EIV strains generally spread from the southern and midwestern regions to other regions. The EIV H3N8 accumulated approximately three nucleotide substitutions per year in the HA gene under heterogeneous local positive selection. Our findings will guide better decision making of target intervention strategies of EIV H3N8 infection and provide the better scheme of genomic surveillance in the United States and global equine health.

South Korean validation of the COVID-related-PTSD scale in a non-clinical sample exposed to the COVID-19 pandemic.

The threat of COVID-19 outbreak in South Korea and around the globe challenged not only physical health but also mental health, increasing the chances of disorders such as posttraumatic stress disorder (PTSD). Such pandemic situation can be referred to a traumatic event for citizens. The present study aims to examine the psychometric properties of the PTSD Checklist (PCL-5), which is named the K-COVID-related-PTSD. The scale measures PTSD symptomology in the context of the COVID-19 pandemic in South Korea. A total of 1434 South Korean citizens were included in this study. The data were statistically analyzed using SPSS 21.0 and Mplus 8.0. The results of confirmatory factor analysis demonstrated a superior fit for the seven-factor hybrid model (x2 = 1425.445 (df = 149), CFI = 0.950, TLI = 0.937, SRMR = 0.033, RMSEA = 0.077) consisting of re-experiencing, negative affect, anxious arousal, dysphoric arousal, avoidance, anhedonia, and externalizing behaviors. Furthermore, the K-COVID-related-PTSD showed a satisfactory level of internal consistency (α = 0.793 to α = 0.939) with good convergent and discriminant validity. Finally, concurrent validity was confirmed by the significant correlations with all the negative mental health outcomes, such as PTSD symptoms, somatization, depression, anxiety, anger, negative affect, job burnout, and suicidal ideation. Overall, the current results demonstrate the K-COVID-related-PTSD is a valid scale and therefore has important implications for future pandemic-related studies.

Corrigendum to: Genomic epidemiology reveals the reduction of the introduction and spread of SARS-CoV-2 after implementing control strategies in Republic of Korea, 2020.

[This corrects the article DOI: 10.1093/ve/veab077.].

Genomic epidemiology reveals the reduction of the introduction and spread of SARS-CoV-2 after implementing control strategies in Republic of Korea, 2020.

Genomic epidemiology is a core component in investigating the spread of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). In this study, the efficacy of control strategies in South Korea was evaluated using genomic epidemiology based on viral genome sequences of 2,065 SARS-CoV-2 cases identified in South Korea from January 2020 to December 2020. Phylogenetic analysis revealed that the majority of viruses introduced from inbound travelers did not further spread throughout South Korea; however, four distinct subgroups (KR.1-4, belonging to B.1.497, B.1, K.1 and B.41) of viruses caused local epidemics. After the introduction of enhanced social distancing, the viral population size and daily case numbers decreased, and KR.2-4 subgroups were extinguished from South Korea. Nevertheless, there was a subsequent increase in KR.1 subgroups after the downgrading of social distancing level. These results indicate that the international traveler quarantine system implemented in South Korea along with social distancing measures efficiently reduced the introduction and spread of SARS-CoV-2, but it was not completely controlled. An improvement of control strategies will be required to better control SARS-CoV-2, its variants, and future pandemic viruses.

Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) in a Dog in Connecticut in February 2021.

We report the first detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in a 3-month-old dog in Connecticut that died suddenly and was submitted to the state veterinary diagnostic laboratory for postmortem examination. Viral RNA was detected in multiple organs of the dog by reverse transcription real time-PCR (RT-qPCR). Negative and positive sense strands of viral RNA were visualized by in situ hybridization using RNAscope technology. Complete genome sequencing and phylogenetic analysis of the hCoV-19/USA/CT-CVMDL-Dog-1/2021 (CT_Dog/2021) virus were conducted to identify the origin and lineage of the virus. The CT_Dog/2021 virus belonged to the GH/B1.2. genetic lineage and was genetically similar to SARS-CoV-2 identified in humans in the U.S. during the winter of 2020-2021. However, it was not related to other SARS-CoV-2 variants identified from companion animals in the U.S. It contained both the D614G in spike and P323L in nsp12 substitutions, which have become the dominant mutations in the United States. The continued sporadic detections of SARS-CoV-2 in companion animals warrant public health concerns about the zoonotic potential of SARS-CoV-2 and enhance our collective understanding of the epidemiology of the virus.

Study of the Pathogen Inactivation Mechanism in Salt-Coated Filters.

As COVID-19 exemplifies, respiratory diseases transmitted through aerosols or droplets are global threats to public health, and respiratory protection measures are essential first lines of infection prevention and control. However, common face masks are single use and can cause cross-infection due to the accumulated infectious pathogens. We developed salt-based formulations to coat membrane fibers to fabricate antimicrobial filters. Here, we report a mechanistic study on salt-induced pathogen inactivation. The salt recrystallization following aerosol exposure was characterized over time on sodium chloride (NaCl), potassium sulfate (K2SO4), and potassium chloride (KCl) powders and coatings, which revealed that NaCl and KCl start to recrystallize within 5 min and K2SO4 within 15 min. The inactivation kinetics observed for the H1N1 influenza virus and Klebsiella pneumoniae matched the salt recrystallization well, which was identified as the main destabilizing mechanism. Additionally, the salt-coated filters were prepared with different methods (with and without a vacuum process), which led to salt coatings with different morphologies for diverse applications. Finally, the salt-coated filters caused a loss of pathogen viability independent of transmission mode (aerosols or droplets), against both DI water and artificial saliva suspensions. Overall, these findings increase our understanding of the salt-recrystallization-based technology to develop highly versatile antimicrobial filters.

Salt coatings functionalize inert membranes into high-performing filters against infectious respiratory diseases.

Respiratory protection is key in infection prevention of airborne diseases, as highlighted by the COVID-19 pandemic for instance. Conventional technologies have several drawbacks (i.e., cross-infection risk, filtration efficiency improvements limited by difficulty in breathing, and no safe reusability), which have yet to be addressed in a single device. Here, we report the development of a filter overcoming the major technical challenges of respiratory protective devices. Large-pore membranes, offering high breathability but low bacteria capture, were functionalized to have a uniform salt layer on the fibers. The salt-functionalized membranes achieved high filtration efficiency as opposed to the bare membrane, with differences of up to 48%, while maintaining high breathability (> 60% increase compared to commercial surgical masks even for the thickest salt filters tested). The salt-functionalized filters quickly killed Gram-positive and Gram-negative bacteria aerosols in vitro, with CFU reductions observed as early as within 5 min, and in vivo by causing structural damage due to salt recrystallization. The salt coatings retained the pathogen inactivation capability at harsh environmental conditions (37 °C and a relative humidity of 70%, 80% and 90%). Combination of these properties in one filter will lead to the production of an effective device, comprehensibly mitigating infection transmission globally.