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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.
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Brotes de Enfermedades , Subtipo H5N1 del Virus de la Influenza A , Gripe Aviar , Filogenia , Gripe Aviar/virología , Gripe Aviar/epidemiología , República de Corea/epidemiología , Animales , Subtipo H5N1 del Virus de la Influenza A/genética , Subtipo H5N1 del Virus de la Influenza A/patogenicidad , Patos/virología , Virus de la Influenza A/genética , Virus de la Influenza A/clasificación , Coinfección/virología , Coinfección/epidemiología , Historia del Siglo XXI , Enfermedades de las Aves de Corral/virología , Enfermedades de las Aves de Corral/epidemiologíaRESUMEN
Acute coronary syndrome is a significant part of cardiac etiology contributing to out-of-hospital cardiac arrest (OHCA), and immediate coronary angiography has been proposed to improve survival. This study evaluated the effectiveness of an AI algorithm in diagnosing near-total or total occlusion of coronary arteries in OHCA patients who regained spontaneous circulation. Conducted from 1 July 2019 to 30 June 2022 at a tertiary university hospital emergency department, it involved 82 OHCA patients, with 58 qualifying after exclusions. The AI used was the Quantitative ECG (QCG™) system, which provides a STEMI diagnostic score ranging from 0 to 100. The QCG score's diagnostic performance was compared to assessments by two emergency physicians and three cardiologists. Among the patients, coronary occlusion was identified in 24. The QCG score showed a significant difference between occlusion and non-occlusion groups, with the former scoring higher. The QCG biomarker had an area under the curve (AUC) of 0.770, outperforming the expert group's AUC of 0.676. It demonstrated 70.8% sensitivity and 79.4% specificity. These findings suggest that the AI-based ECG biomarker could predict coronary occlusion in resuscitated OHCA patients, and it was non-inferior to the consensus of the expert group.
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PURPOSE: Prehospital telecardiology facilitates early ST-elevation myocardial infarction (STEMI) detection, yet its widespread implementation remains challenging. Extracting digital STEMI biomarkers from printed electrocardiograms (ECGs) using phone cameras could offer an affordable and scalable solution. This study assessed the feasibility of this approach with real-world prehospital ECGs. MATERIALS AND METHODS: Patients suspected of having STEMI by emergency medical technicians (EMTs) were identified from a policy research dataset. A deep learning-based ECG analyzer (QCG™ analyzer) extracted a STEMI biomarker (qSTEMI) from prehospital ECGs. The biomarker was compared to a group of human experts, including five emergency medical service directors (board-certified emergency physicians) and three interventional cardiologists based on their consensus score (number of participants answering "yes" for STEMI). Non-inferiority of the biomarker was tested using a 0.100 margin of difference in sensitivity and specificity. RESULTS: Among 53 analyzed patients (24 STEMI, 45.3%), the area under the receiver operating characteristic curve of qSTEMI and consensus score were 0.815 (0.691-0.938) and 0.736 (0.594-0.879), respectively (p=0.081). Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of qSTEMI were 0.750 (0.583-0.917), 0.862 (0.690-0.966), 0.826 (0.679-0.955), and 0.813 (0.714-0.929), respectively. For the consensus score, sensitivity, specificity, PPV, and NPV were 0.708 (0.500-0.875), 0.793 (0.655-0.966), 0.750 (0.600-0.941), and 0.760 (0.655-0.880), respectively. The 95% confidence interval of sensitivity and specificity differences between qSTEMI and consensus score were 0.042 (-0.099-0.182) and 0.103 (-0.043-0.250), respectively, confirming qSTEMI's non-inferiority. CONCLUSION: The digital STEMI biomarker, derived from printed prehospital ECGs, demonstrated non-inferiority to expert consensus, indicating a promising approach for enhancing prehospital telecardiology.
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Servicios Médicos de Urgencia , Infarto del Miocardio , Infarto del Miocardio con Elevación del ST , Humanos , Infarto del Miocardio con Elevación del ST/diagnóstico , Infarto del Miocardio/diagnóstico , Teléfono Inteligente , Electrocardiografía , BiomarcadoresRESUMEN
BACKGROUND: Relatively little is known about thrombotic adverse events (AEs) of emicizumab in postmarketing real-world settings, particularly in comparison with factor VIII (FVIII) products. A recent European study reported a potentially greater thrombotic risk of emicizumab compared with FVIII products. OBJECTIVES: This drug safety study aims to investigate whether thrombotic AEs are more frequently reported for emicizumab than for FVIII products and if so, whether it is independent of bypassing agents as coreporting drugs using the United States Food and Drug Administration Adverse Event Reporting System data. METHODS: Disproportionality analyses for thrombotic AEs of emicizumab vs FVIII products were conducted. Three signal detection indicators were used: proportional reporting ratio (PRR), reporting odds ratio (ROR), and informational component (IC). RESULTS: During 2018-2022, the proportions of thrombotic AEs among all AEs were 4.07% (97 out of 2383) and 1.44% (134 out of 9324) for emicizumab and FVIII products, respectively: PRR = 2.83 (2.19-3.66), ROR = 2.91 (2.23-3.79), and IC = 1.04 (0.70-1.28). Bypassing agents as coreporting drugs were identified in 36% and 15% of the total thrombotic AE reports associated with emicizumab and FVIII products, respectively. Even after thrombotic AE reports with bypassing agents were excluded, the reporting proportion of thrombotic AEs was still greater for emicizumab than for FVIII products: PRR = 2.19 (1.60-2.99). CONCLUSION: Thrombotic AEs in the United States Food and Drug Administration Adverse Event Reporting System data were about 3 times more frequently reported for emicizumab than for FVIII products. More research and efforts in the future are warranted for monitoring, elucidating, and preventing the potential risk of thrombotic AEs in hemophilia therapy, including emicizumab.
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Sistemas de Registro de Reacción Adversa a Medicamentos , Anticuerpos Biespecíficos , Anticuerpos Monoclonales Humanizados , Factor VIII , Trombosis , United States Food and Drug Administration , Humanos , Estados Unidos , Anticuerpos Monoclonales Humanizados/efectos adversos , Anticuerpos Monoclonales Humanizados/uso terapéutico , Trombosis/inducido químicamente , Trombosis/epidemiología , Anticuerpos Biespecíficos/efectos adversos , Factor VIII/efectos adversos , Hemofilia A/tratamiento farmacológico , Hemofilia A/sangre , Factores de Riesgo , Coagulantes/efectos adversos , Coagulantes/uso terapéutico , Medición de Riesgo , Bases de Datos FactualesRESUMEN
Since 2014, periodic outbreaks of high pathogenicity avian influenza (HPAI) caused by clade 2.3.4.4 H5 HPAI virus (HPAIV) have resulted in huge economic losses in the Korean poultry industry. During the winter season of 2016-2017, clade 2.3.4.4e H5N6 HPAIVs classified into 5 subgroups (C1-5) were introduced into South Korea. Interestingly, it was revealed that the subgroup C2 and C4 viruses were predominantly distributed throughout the country, whereas detection of the subgroup C3 viruses was confined in a specific local region. In the present study, we conducted comparative evaluation of the pathogenicity of viruses belonging to subgroups C2 and C3 (H15 and HN1 strains) in specific pathogen-free (SPF) chickens, and further compared them with previously determined pathogenicity of subgroup C4 (ES2 strain) virus. The HN1 strain showed lower viral replication in tissues, less transmissibility, and higher mean chicken lethal dose than the H15 and ES2 strains in SPF chickens. Considering that the HN1 strain has a different NS gene segment from the H15 and ES2 strains, the reassortment of the NS gene segment likely affects their infectivity and transmissibility in chickens. These findings emphasize the importance of monitoring the genetic characteristics and pathogenic features of HPAIVs to effectively control their outbreaks in the field.
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Pollos , Gripe Aviar , Animales , Subtipo H5N6 del Virus de la Influenza A , Virulencia , Gripe Aviar/epidemiología , Brotes de Enfermedades/veterinaria , FilogeniaRESUMEN
BACKGROUND: Hyperkalemia is a potentially fatal condition that mandates rapid identification in emergency departments (EDs). Although a 12-lead electrocardiogram (ECG) can indicate hyperkalemia, subtle changes in the ECG often pose detection challenges. An artificial intelligence application that accurately assesses hyperkalemia risk from ECGs could revolutionize patient screening and treatment. We aimed to evaluate the efficacy and reliability of a smartphone application, which utilizes camera-captured ECG images, in quantifying hyperkalemia risk compared to human experts. METHODS: We performed a retrospective analysis of ED hyperkalemic patients (serum potassium ≥ 6 mmol/L) and their age- and sex-matched non-hyperkalemic controls. The application was tested by five users and its performance was compared to five board-certified emergency physicians (EPs). RESULTS: Our study included 125 patients. The area under the curve (AUC)-receiver operating characteristic of the application's output was nearly identical among the users, ranging from 0.898 to 0.904 (median: 0.902), indicating almost perfect interrater agreement (Fleiss' kappa 0.948). The application demonstrated high sensitivity (0.797), specificity (0.934), negative predictive value (NPV) (0.815), and positive predictive value (PPV) (0.927). In contrast, the EPs showed moderate interrater agreement (Fleiss' kappa 0.551), and their consensus score had a significantly lower AUC of 0.662. The physicians' consensus demonstrated a sensitivity of 0.203, specificity of 0.934, NPV of 0.527, and PPV of 0.765. Notably, this performance difference remained significant regardless of patients' sex and age (P < 0.001 for both). CONCLUSION: Our findings suggest that a smartphone application can accurately and reliably quantify hyperkalemia risk using initial ECGs in the ED.
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Hiperpotasemia , Médicos , Humanos , Hiperpotasemia/diagnóstico , Inteligencia Artificial , Estudios Retrospectivos , Teléfono Inteligente , Reproducibilidad de los Resultados , Servicio de Urgencia en Hospital , Electrocardiografía/métodosRESUMEN
High pathogenicity avian influenza (HPAI) viruses of clade 2.3.4.4 H5Nx have been circulating in poultry and wild birds worldwide since 2014. In South Korea, after the first clade 2.3.4.4b H5N1 HPAI viruses were isolated from wild birds in October 2021, additional HPAIV outbreaks occurred in poultry farms until April 2022. In this study, we genetically characterized clade 2.3.4.4b H5N1 HPAIV isolates in 2021-2022 and examined the pathogenicity and transmissibility of A/mandarin duck/Korea/WA585/2021 (H5N1) (WA585/21) in chickens and ducks. Clade 2.3.4.4b H5N1 HPAI viruses caused 47 outbreaks in poultry farms and were also detected in multiple wild birds. Phylogenetic analysis of HA and NA genes indicated that Korean H5N1 HPAI isolates were closely related to Eurasian viruses isolated in 2021-2022. Four distinct genotypes of H5N1 HPAI viruses were identified in poultry, and the majority were also found in wild birds. WA585/21 inoculated chickens showed virulent pathogenicity with high mortality and transmission. Meanwhile, ducks infected with the virus showed no mortality but exhibited high rates of transmission and longer viral shedding than chickens, suggesting that they may play an important role as silent carriers. In conclusion, consideration of both genetic and pathogenic traits of H5N1 HPAI viruses is required for effective viral control.
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Subtipo H5N1 del Virus de la Influenza A , Virus de la Influenza A , Gripe Aviar , Animales , Pollos , Virulencia , Filogenia , Virus de la Influenza A/genética , Patos , Aves de Corral , Animales Salvajes , República de Corea/epidemiologíaRESUMEN
The H9N2 avian influenza (AI) has become endemic in poultry in many countries since the 1990s, which has caused considerable economic losses in the poultry industry. Considering the long history of the low pathogenicity H9N2 AI in many countries, once H9N2 AI is introduced, it is more difficult to eradicate than high pathogenicity AI. Various preventive measures and strategies, including vaccination and active national surveillance, have been used to control the Y439 lineage of H9N2 AI in South Korea, but it took a long time for the H9N2 virus to disappear from the fields. By contrast, the novel Y280 lineage of H9N2 AI was introduced in June 2020 and has spread nationwide. This study reviews the history, genetic and pathogenic characteristics, and control strategies for Korean H9N2 AI. This review may provide some clues for establishing control strategies for endemic AIV and a newly introduced Y280 lineage of H9N2 AI in South Korea.
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Subtipo H9N2 del Virus de la Influenza A , Gripe Aviar , Enfermedades de las Aves de Corral , Animales , Subtipo H9N2 del Virus de la Influenza A/genética , Gripe Aviar/epidemiología , Gripe Aviar/prevención & control , Filogenia , Aves de Corral , Enfermedades de las Aves de Corral/epidemiología , Enfermedades de las Aves de Corral/prevención & control , República de Corea/epidemiologíaRESUMEN
Although diverse cell penetrating motifs not only from naturally occurring proteins but also from synthetic peptides have been discovered and developed, the selectivity of cargo delivery connected to these motifs into the desired target cells is generally low. Here, we demonstrate the selective cytotoxicity tuning of an anticancer KLA peptide with a cell penetrating motif activatable by matrix metalloproteinase-2 (MMP2). The anionic masking sequence introduced at the end of the KLA peptide through an MMP2-cleavable linker is selectively cleaved by MMP2 and the cationic cell penetrating motif is activated. Upon treatment of the peptide to H1299 cells (high MMP2 level), it is selectively internalized into the cells by MMP2, which consequently induces membrane disruption and cell death. In contrast, the peptide shows negligible cytotoxicity toward A549 cancer cells with low MMP2 levels. Furthermore, the selective therapeutic efficacy of the peptide induced by MMP2 is also corroborated using in vivo study.
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During 2014-2016, clade 2.3.4.4 H5N8 high pathogenicity avian influenza virus (HPAIV) caused the largest known avian influenza epidemic in South Korea. Based on data from earlier H5N8 outbreaks, primitive H5N8 virus in South Korea was classified into five subgroups: C1, C2, C3, C4, and C5. The present study investigated the pathogenic and molecular epidemiologic characteristics of H5N8 viruses obtained from 388 cases of poultry farms and 85 cases of wild bird infections in South Korea during 2014-2016. Representative viruses of subgroups C1, C2, and C4 showed significant pathobiological differences in specific pathogen-free (SPF) chickens, with the H1731 (C1) virus showing substantially lower infectivity, transmissibility, and pathogenicity than the H2102 (C2) and H1924 (C4) viruses. Full genome sequence analysis showed the number of mutations that significantly increased in domestic duck-origin H5N8 HPAIVs compared to the viruses from gallinaceous poultry. These differences may have been due to the long-term circulation of viruses in domestic duck farms. The same mutations, at positions 219 and 757 of PB1, independently evolving in the C0, C1, and C2 subgroups may have been positively selected, resulting in convergent evolution at the amino acid level. Bayesian discrete trait phylodynamic analysis (DTA) indicated multiple introductions of H5N8 HPAIV from wild birds into domestic poultry in various regions in South Korea. Following initial viral introduction into domestic duck farms in the western part of Korea, domestic ducks played a major role in viral transmission and maintenance. These findings highlight the need for continued genomic surveillance and pathobiological characterization of HPAIV in birds. Enhanced biosecurity in poultry farms should be implemented to prevent the introduction, maintenance, and spread of HPAIV.
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BACKGROUND: Smartphone-based ECG analyzer using camera input can be useful as everyone have it. The purpose of this study was to evaluate whether such a system can outperform clinicians in detecting ST-elevation myocardial infarction (STEMI) regardless of image acquisition conditions. METHODS: We retrospectively enrolled suspected STEMI patients in an emergency department from January to October 2021. A multifaceted cardiovascular assessment system (Quantitative ECG, QCG™) using ECG images to produce a quantitative score (QCG score, ranging from 0 to 100) was compared to human experts of 7 emergency physicians and 3 cardiologists. Voting scores (number of participants answering "yes" for STEMI) were calculated for comparison. The system's robustness was evaluated using an equivalence test where we prove its performance metric (area under the curve of the receiver operating characteristic curve, AUC-ROC) changes within a predetermined equivalence range (-0.01 to 0.01) in 6 different environments (A combination of three different smartphones and two image sources including computer screen and paper). RESULTS: 187 patients (96 STEMI, 51.3%) were analyzed. AUC-ROC of QCG score was 0.919 (0.880-0.957). AUC-ROCs of voting scores, 0.856 (0.799-0.913) for all clinicians, 0.843 (0.786-0.900) for emergency physicians, 0.817 (0.756-0.877) for cardiologists, and 0.848 (0.790-0.905) for high-performance group were significantly lower compared to that of QCG score. The change in AUC-ROC by image acquisition condition was negligible with a narrow confidence interval within -0.01 to 0.01 confirming the equivalence. CONCLUSIONS: Image-based AI system can outperform clinicians in STEMI diagnosis and its performance was robust to change in image acquisition conditions.
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Médicos , Infarto del Miocardio con Elevación del ST , Inteligencia Artificial , Electrocardiografía/métodos , Humanos , Estudios Retrospectivos , Infarto del Miocardio con Elevación del ST/diagnóstico por imagenRESUMEN
High pathogenicity H5N1 avian influenza viruses pose a threat to both animal and human health worldwide. In late 2020, outbreaks of H5 high pathogenicity avian influenza viruses belonging to clade 2.3.4.4b emerged in Europe, following on from outbreaks in East Asia in earlier years. However, very recent studies show that clade 2.3.4.4b H5N1, rather than 2.3.4.4b H5N8, has become predominant in wild birds and has infected poultry in several countries. In this study, we describe isolation of a novel H5N1 virus from a captured mandarin duck in South Korea, and another H5N1 virus from a quail farm. We performed genetic analysis of these two viruses to identify their origin and to determine their relationship with the clade 2.3.4.4b H5N1 viruses currently circulating in Europe. Based on our results, it is presumed that the novel H5N1 virus isolated in Korea originated from an unknown reassortant between clade 2.3.4.4b H5N8 viruses circulating from 2020 and other Eurasian viruses, with additional reassortment of genes and point mutations that discriminate them from the recently reported H5N1 virus in Europe.
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Subtipo H5N1 del Virus de la Influenza A , Virus de la Influenza A , Gripe Aviar , Animales , Humanos , Subtipo H5N1 del Virus de la Influenza A/genética , Virus de la Influenza A/genética , Gripe Aviar/epidemiología , Filogenia , Aves de Corral , Virus Reordenados/genética , República de Corea/epidemiología , VirulenciaRESUMEN
BACKGROUND: Rapid revascularization is the key to better patient outcomes in ST-elevation myocardial infarction (STEMI). Direct activation of cardiac catheterization laboratory (CCL) using artificial intelligence (AI) interpretation of initial electrocardiography (ECG) might help reduce door-to-balloon (D2B) time. To prove that this approach is feasible and beneficial, we assessed the non-inferiority of such a process over conventional evaluation and estimated its clinical benefits, including a reduction in D2B time, medical cost, and 1-year mortality. METHODS: This is a single-center retrospective study of emergency department (ED) patients suspected of having STEMI from January 2021 to June 2021. Quantitative ECG (QCG™), a comprehensive cardiovascular evaluation system, was used for screening. The non-inferiority of the AI-driven CCL activation over joint clinical evaluation by emergency physicians and cardiologists was tested using a 5% non-inferiority margin. RESULTS: Eighty patients (STEMI, 54 patients [67.5%]) were analyzed. The area under the curve of QCG score was 0.947. Binned at 50 (binary QCG), the sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were 98.1% (95% confidence interval [CI], 94.6%, 100.0%), 76.9% (95% CI, 60.7%, 93.1%), 89.8% (95% CI, 82.1%, 97.5%) and 95.2% (95% CI, 86.1%, 100.0%), respectively. The difference in sensitivity and specificity between binary QCG and the joint clinical decision was 3.7% (95% CI, -3.5%, 10.9%) and 19.2% (95% CI, -4.7%, 43.1%), respectively, confirming the non-inferiority. The estimated median reduction in D2B time, evaluation cost, and the relative risk of 1-year mortality were 11.0 minutes (interquartile range [IQR], 7.3-20.0 minutes), 26,902.2 KRW (22.78 USD) per STEMI patient, and 12.39% (IQR, 7.51-22.54%), respectively. CONCLUSION: AI-assisted CCL activation using initial ECG is feasible. If such a policy is implemented, it would be reasonable to expect some reduction in D2B time, medical cost, and 1-year mortality.
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Infarto del Miocardio , Infarto del Miocardio con Elevación del ST , Inteligencia Artificial , Servicio de Urgencia en Hospital , Humanos , Infarto del Miocardio/diagnóstico , Estudios Retrospectivos , Infarto del Miocardio con Elevación del ST/diagnóstico , Factores de TiempoRESUMEN
The past two decades have seen the emergence of highly pathogenic avian influenza (HPAI) infections that are characterized as extremely contagious, with a high fatality rate in chickens, and humans; this has sparked considerable concerns for global health. Generally, the new variant of the HPAI virus crossed into various countries through wild bird migration, and persisted in the local environment through the interactions between wild and farmed birds. Nevertheless, no studies have found informative cases associated with connecting local persistence and long-range dispersal. During the 2016-2017 HPAI H5N6 epidemic in South Korea, we observed several waterfowls with avian influenza infection under telemetric monitoring. Based on the telemetry records and surveillance data, we conducted a case study to test hypotheses related to the transmission pathway between wild birds and poultry. One sedentary wildfowl naturally infected with HPAI H5N6, which overlapped with the home range of one migratory bird with H5-specific antibody-positive, showed itself to be phylogenetically close to the isolates from a chicken farm located within its habitat. Our study is the first observational study that provides scientific evidence supporting the hypothesis that the HPAI spillover into poultry farms is caused by local persistence in sedentary birds, in addition to its long-range dispersal by sympatric migratory birds.
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Brotes de Enfermedades/veterinaria , Virus de la Influenza A/aislamiento & purificación , Gripe Aviar/epidemiología , Gripe Aviar/virología , Enfermedades de las Aves de Corral/epidemiología , Enfermedades de las Aves de Corral/virología , Animales , Animales Salvajes/virología , Pollos , Epidemias , Granjas , Humanos , Virus de la Influenza A/clasificación , Filogenia , Aves de Corral/virología , República de Corea/epidemiologíaRESUMEN
Human infection by avian-origin subtype H10 influenza viruses has raised concerns about the pandemic potential of these microbes. H10 subtype low pathogenic avian influenza viruses (LPAIVs) have been isolated from wild birds and poultry worldwide. Here, we isolated 36 H10 LPAIVs from wild bird habitats (a mean annual rate of 3.8% of all avian influenza virus isolations) from January 2010 to April 2019 through a nationwide active surveillance program for avian influenza viruses (AIVs). Phylogenetic analysis revealed that the haemagglutinin (HA) gene of H10 isolates formed eight distinct genetic subgroups (HA-A-H). Unlike other Eurasian-origin subgroups, the HA-H subgroup belonged to the North American lineage. Gene-constellation analysis revealed that 24 H10 LPAIVs constituted ≥18 distinct genotypes, representing high levels of genetic diversity. An intravenous pathogenicity index (IVPI) experiment showed that the pathogenicity of representative strains of the HA-B, E and G subgroups possessing an IVPI score >1.2 was associated with replication capacity in the chicken kidney in the absence of trypsin. Intranasal inoculation experiments showed that a representative strain of the HA-D subgroup replicated and transmitted in chickens without clinical signs. Subclinical virus shedding in chickens may contribute to its silent spread among the poultry population. Moreover, six representative viruses replicated in the lungs of mice without prior adaptation and a representative strain of the HA-C subgroup caused 40% mortality, with severe body weight loss. These findings highlight the importance of intensive surveillance of wild bird habitats, poultry farms and the animal-human interface, along with appropriate risk assessment of isolated viruses.
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Virus de la Influenza A , Gripe Aviar , Enfermedades de los Roedores , Animales , Animales Salvajes , Pollos , Hemaglutininas , Humanos , Gripe Aviar/epidemiología , Ratones , Filogenia , Aves de Corral , Tripsina/genéticaRESUMEN
Zoonotic infection with avian influenza viruses (AIVs) of subtype H7, such as H7N9 and H7N4, has raised concerns worldwide. During the winter of 2020-2021, five novel H7 low pathogenic AIVs (LPAIVs) containing different neuraminidase (NA) subtypes, including two H7N3, an H7N8, and two H7N9, were detected in wild bird feces in South Korea. Complete genome sequencing and phylogenetic analysis showed that the novel H7Nx AIVs were reassortants containing two gene segments (hemagglutinin (HA) and matrix) that were related to the zoonotic Jiangsu-Cambodian H7 viruses causing zoonotic infection and six gene segments originating from LPAIVs circulating in migratory birds in Eurasia. A genomic constellation analysis demonstrated that all H7 isolates contained a mix of gene segments from different viruses, indicating that multiple reassortment occurred. The well-known mammalian adaptive substitution (E627K and D701N) in PB2 was not detected in any of these isolates. The detection of multiple reassortant H7Nx AIVs in wild birds highlights the need for intensive surveillance in both wild birds and poultry in Eurasia.
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Subtipo H7N3 del Virus de la Influenza A/genética , Subtipo H7N9 del Virus de la Influenza A/genética , Gripe Aviar/virología , Animales , Animales Salvajes/virología , Aves/genética , Aves/virología , Glicoproteínas Hemaglutininas del Virus de la Influenza/genética , Subtipo H7N3 del Virus de la Influenza A/aislamiento & purificación , Subtipo H7N3 del Virus de la Influenza A/patogenicidad , Subtipo H7N9 del Virus de la Influenza A/aislamiento & purificación , Subtipo H7N9 del Virus de la Influenza A/patogenicidad , Gripe Aviar/epidemiología , Filogenia , República de Corea/epidemiologíaRESUMEN
During the 2020-2021 winter season, an outbreak of clade 2.3.4.4b H5N8 high pathogenicity avian influenza (HPAI) virus occurred in South Korea. Here, we evaluated the pathogenicity and transmissibility of A/mandarin duck/Korea/H242/2020 (H5N8) (H242/20(H5N8)) first isolated from this outbreak in specific pathogen-free (SPF) chickens and commercial ducks in comparison with those of A/duck/Korea/HD1/2017(H5N6) (HD1/17(H5N6)) from a previous HPAI outbreak in 2017-2018. In chickens, the 50% chicken lethal dose and mean death time of H242/20(H5N8) group were 104.5 EID50 and 4.3 days, respectively, which indicate less virulent than those of HD1/17(H5N6) (103.6 EID50 and 2.2 days). Whereas, chickens inoculated with H242/20(H5N8) survived longer and had a higher titer of viral shedding than those inoculated with HD1/17(H5N6), which may increase the risk of viral contamination on farms. All ducks infected with either HPAI virus survived without clinical symptoms. In addition, they exhibited a longer virus shedding period and a higher transmission rate, indicating that ducks may play an important role as a silent carrier of both HPAI viruses. These results suggest that the pathogenic characteristics of HPAI viruses in chickens and ducks need to be considered to effectively control HPAI outbreaks in the field.
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Subtipo H5N8 del Virus de la Influenza A/patogenicidad , Gripe Aviar/epidemiología , Gripe Aviar/virología , Enfermedades de las Aves de Corral/epidemiología , Enfermedades de las Aves de Corral/virología , Animales , Pollos/virología , Brotes de Enfermedades/veterinaria , Patos/virología , Subtipo H5N8 del Virus de la Influenza A/clasificación , Subtipo H5N8 del Virus de la Influenza A/aislamiento & purificación , Virus de la Influenza A/clasificación , Gripe Aviar/transmisión , Enfermedades de las Aves de Corral/transmisión , República de Corea/epidemiología , Organismos Libres de Patógenos Específicos , Virulencia , Esparcimiento de VirusRESUMEN
Samples from 29 adult Gentoo (Pygoscelis papua), Chinstrap (Pygoscelis antarcticus), and Adélie Penguins (Pygoscelis adeliae) at the King Sejong Station on NarÌ¢ ebski Point, King George Island, Antarctica, were investigated to detect antibodies to avian influenza, Newcastle disease virus, infectious bursal disease virus, infectious bronchitis virus, Mycoplasma, and Salmonella. Antibodies were identified from one Gentoo Penguin and one Chinstrap Penguin against infectious bronchitis virus; from one Gentoo Penguin against Newcastle disease virus; from one Gentoo Penguin against Mycoplasma synoviae; and from two Chinstrap Penguins against Salmonella pullorum. Thirty-three dead penguin chicks were collected from the breeding colony for necropsy, histopathological examination, and polymerase chain reaction. Pulmonary hemorrhage and congestion were the main necropsy findings.