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Emerging Infectious Diseases Apr 2024We report full-genome characterization of highly pathogenic avian influenza A(H5N1) clade 2.3.4.4b virus from an outbreak among sea lions (August 2023) in Argentina and...
We report full-genome characterization of highly pathogenic avian influenza A(H5N1) clade 2.3.4.4b virus from an outbreak among sea lions (August 2023) in Argentina and possible spillover to fur seals and terns. Mammalian adaptation mutations in virus isolated from marine mammals and a human in Chile were detected in mammalian and avian hosts.
Topics: Animals; Humans; Influenza A Virus, H5N1 Subtype; Influenza in Birds; Argentina; Influenza A virus; Birds; Disease Outbreaks; Phylogeny; Mammals
PubMed: 38413243
DOI: 10.3201/eid3004.231725 -
Viruses Sep 2020From 2016 to 2018, surveillance of influenza A viruses in wild birds was conducted in Shanghai, located at the East Asian-Australian flyway, China. A total of 5112...
From 2016 to 2018, surveillance of influenza A viruses in wild birds was conducted in Shanghai, located at the East Asian-Australian flyway, China. A total of 5112 samples from 51 species of wild birds were collected from three different wetlands. The total three-year prevalence of influenza A viruses among them was 8.8%, as assessed using real-time polymerase chain reaction (PCR) methods, and the total prevalence was higher in Anseriformes (26.3%) than in the Charadriiformes (2.3%) and the other orders (2.4%) in the Chongmin wetlands. Anseriformes should be the key monitoring group in future surveillance efforts. The peak prevalence of influenza A viruses in Charadriiformes were in April and September, and in other bird orders, the peaks were in November and December. Twelve subtypes of haemagglutinin (HA; H1-H12) and eight subtypes of neuraminidase (NA; N1, N2, N4-N9) were identified in 21 different combinations. The greatest subtype diversity could be found in common teal, suggesting that this species of the bird might play an important role in the ecology and epidemiology of influenza A viruses in Shanghai. These results will increase our understanding of the ecology and epidemiology of influenza A viruses in wild bird hosts in eastern China, and provide references for subsequent surveillance of influenza A virus in wild birds in this area.
Topics: Animals; Animals, Wild; Anseriformes; Biodiversity; Birds; Charadriiformes; Influenza A virus; Influenza in Birds; Neuraminidase; Phylogeny; Seasons; Sequence Analysis
PubMed: 32948009
DOI: 10.3390/v12091031 -
Journal of Virology Feb 2022A 2-year surveillance study of influenza A viruses in migratory birds was conducted to understand the subsequent risk during the migratory seasons in Dandong Yalu River...
A 2-year surveillance study of influenza A viruses in migratory birds was conducted to understand the subsequent risk during the migratory seasons in Dandong Yalu River Estuary Coastal Wetland National Nature Reserve, Liaoning Province, China, a major stopover site on the East Asian-Australasian flyway. Overall, we isolated 27 influenza A viruses with multiple subtypes, including H3N8 ( = 2), H4N6 ( = 2), H4N7 ( = 2), H7N4 ( = 9), H7N7 ( = 1), H10N7 ( = 7), and H13N6 ( = 4). Particularly, a novel reassortant influenza A(H7N4) virus was first identified in a woman and her backyard poultry flock in Jiangsu Province, China, posing a serious threat to public health. Here, we describe the genetic characterization and pathogenicity of the nine influenza A(H7N4) isolates. Phylogenetic analysis indicated that complex viral gene flow occurred among Asian countries. We also demonstrated a similar evolutionary trajectory of the surface genes of the A(H7N4) isolates and Jiangsu human-related A(H7N4) viruses. Our A(H7N4) isolates exhibited differing degrees of virulence in mice, suggesting a potential risk to other mammalian species, including humans. We revealed multiple mutations that might affect viral virulence in mice. Our report highlights the importance and need for the long-term surveillance of avian influenza virus in migratory birds combined with domestic poultry surveillance along migratory routes and flyways and, thereby, the development of measures to manage potential health threats. The H7 subtype avian influenza viruses, such as H7N2, H7N3, H7N4, H7N7, and H7N9, were documented as being capable of infecting humans, and the H7 subtype low pathogenicity avian influenza viruses are capable of mutating into highly pathogenic avian influenza; therefore, they pose a serious threat to public health. Here, we investigated the evolutionary history, molecular characteristics, and pathogenicity of shorebird-origin influenza A(H7N4) viruses, showing a similar evolutionary trajectory with Jiangsu human A(H7N4) viruses in HA and NA genes. Moreover, our isolates exhibited variable virulence (including moderate virulence) in mice, suggesting a potential risk to other mammalian species, including humans.
Topics: Animals; Biological Evolution; Birds; China; Communicable Diseases, Emerging; Conserved Sequence; Disease Models, Animal; Disease Susceptibility; Evolution, Molecular; Female; Influenza A Virus, H7N7 Subtype; Influenza in Birds; Mice; Mutation; Phylogeny; Phylogeography; Position-Specific Scoring Matrices; RNA, Viral; Virulence
PubMed: 34787451
DOI: 10.1128/JVI.01717-21 -
Viruses Nov 2023Avian influenza viruses pose significant threats to both the poultry industry and public health worldwide. Among them, the H9N2 subtype has gained substantial attention...
Avian influenza viruses pose significant threats to both the poultry industry and public health worldwide. Among them, the H9N2 subtype has gained substantial attention due to its high prevalence, especially in Asia, the Middle East, and Africa; its ability to reassort with other influenza viruses; and its potential to infect humans. This study presents a comprehensive phylogenetic and molecular analysis of H9N2 avian influenza viruses circulating in Morocco from 2021 to 2023. Through an active epidemiological survey, a total of 1140 samples (trachea and lungs) and oropharyngeal swabs pooled into 283 pools, collected from 205 farms located in 7 regions of Morocco known for having a high density of poultry farms, were analyzed. Various poultry farms were investigated (159 broiler farms, 24 layer farms, 10 breeder farms, and 12 turkey breeder farms). A total of 21 AI H9N2 strains were isolated, and in order to understand the molecular evolution of the H9N2 avian influenza virus, their genetic sequences were determined using the Sanger sequencing technique. Phylogenetic analysis was performed using a dataset comprising global H9N2 sequences to determine the genetic relatedness and evolutionary dynamics of the Moroccan strains. The results revealed the continued circulation and diversification of H9N2 avian influenza viruses in Morocco during the study period. Real-time RT-PCR showed a positivity rate of 35.6% (73/205), with cycle threshold values ranging from 19.2 to 34.9. The phylogenetic analysis indicated that all Moroccan strains belonged to a G1-like lineage and regrouped into two distinct clusters. Our newly detected isolates aggregated distinctly from the genotypes previously isolated in Morocco, North and West Africa, and the Middle East. This indicats the potential of virus evolution resulting from both national circulation and cross-border transmission. A high genetic diversity at both nucleotide and amino-acid levels was observed among all the strains isolated in this study, as compared to H9N2 strains isolated in Morocco since 2016, which suggests the co-circulation of genetically diverse H9N2 variants. Newly discovered mutations were detected in hemagglutinin positions 226, 227, and 193 (H3 numbering), which highlights the genetic evolution of the H9N2 AIVs. These findings contribute to our understanding of the evolution and epidemiology of H9N2 in the region and provide valuable insights for the development of effective prevention and control strategies against this emerging avian influenza subtype.
Topics: Humans; Animals; Influenza in Birds; Influenza A Virus, H9N2 Subtype; Morocco; Phylogeny; Chickens; Poultry; Evolution, Molecular
PubMed: 38140596
DOI: 10.3390/v15122355 -
Nature Communications Oct 2022Cell-based assays can monitor virus infection at a single-cell level with high sensitivity and cost-efficiency. For this purpose, it is crucial to develop molecular...
Cell-based assays can monitor virus infection at a single-cell level with high sensitivity and cost-efficiency. For this purpose, it is crucial to develop molecular probes that respond selectively to physiological changes in live cells. We report stimuli-responsive light-emitters built on a T-shaped benzimidazole platform, and consecutive borylation reactions to produce a library of homologs displaying systematic changes in fluorescence quantum yield and environmental sensitivity. We find that certain fluorophores localize selectively at the endoplasmic reticulum, and interact with proteins involved in the stress signaling pathways. Notably, the mono-borylated compound responds selectively to the stress conditions by enhancing fluorescence, and detects avian influenza virus infection at the single-cell level. Our findings demonstrate the unprecedented practical utility of the stress-responsive molecular probes to differentiate cellular states for early diagnosis.
Topics: Animals; Benzimidazoles; Endoplasmic Reticulum; Fluorescent Dyes; Influenza A virus; Influenza in Birds; Molecular Probes
PubMed: 36192426
DOI: 10.1038/s41467-022-33586-1 -
Emerging Infectious Diseases Aug 2022Although reports of human infection with influenza A(H5N6) increased in 2021, reports of similar H5N6 virus infection in poultry are few. We detected 10 avian influenza...
Although reports of human infection with influenza A(H5N6) increased in 2021, reports of similar H5N6 virus infection in poultry are few. We detected 10 avian influenza A(H5N6) clade 2.3.4.4b viruses in poultry from 4 provinces in China. The viruses showed strong immune-escape capacity and complex genetic reassortment, suggesting further transmission risk.
Topics: Animals; Birds; China; Humans; Influenza A virus; Influenza in Birds; Influenza, Human; Phylogeny; Poultry; Reassortant Viruses
PubMed: 35820171
DOI: 10.3201/eid2808.212241 -
Med (New York, N.Y.) Jan 2024Recent outbreaks of avian influenza and ongoing virus reassortment have drawn focus on spill-over infections. The increase in human infections with highly pathogenic...
BACKGROUND
Recent outbreaks of avian influenza and ongoing virus reassortment have drawn focus on spill-over infections. The increase in human infections with highly pathogenic avian influenza H5N6 virus and its high fatality rate posed a potential threat, necessitating the search for a more effective treatment.
METHODS
Longitudinal clinical data and specimens were collected from five H5N6 patients after admission. All patients received antiviral treatment of either sequential monotherapy of oseltamivir and baloxavir or the two drugs in combination. Severity of illness; viral load in sputum, urine, and blood; and cytokine levels in serum and sputum were serially analyzed.
FINDINGS
All patients developed acute respiratory distress syndrome (ARDS) and viral sepsis within 1 week after disease onset. When delayed oseltamivir showed poor effects, baloxavir was administered and rapidly decreased viral load. In addition, levels of IL-18, M-CSF, IL-6, and HGF in sputum and Mig and IL-18 in serum that reflected ARDS and sepsis deterioration, respectively, were also reduced with baloxavir usage. However, three patients eventually died from exacerbation of underlying disease and secondary bacterial infection. Nonsurvivors had more severe extrapulmonary organ dysfunction and insufficient H5N6 virus-specific antibody response.
CONCLUSIONS
For critical human cases of H5N6 infection, baloxavir demonstrated effects on viral load and pulmonary/extrapulmonary cytokines, even though treatment was delayed. Baloxavir could be regarded as a first-line treatment to limit continued viral propagation, with potential future application in avian influenza human infections and poultry workers exhibiting influenza-like illness.
FUNDING
This work was funded by the National Natural Science Foundation of China (81761128014).
Topics: Animals; Humans; Influenza in Birds; Oseltamivir; Influenza A Virus, H5N6 Subtype; Interleukin-18; Influenza, Human; Influenza A virus; Respiratory Distress Syndrome; Sepsis; Dibenzothiepins; Morpholines; Pyridones; Triazines
PubMed: 38070511
DOI: 10.1016/j.medj.2023.11.001 -
Microbes and Infection 2021We investigated fluctuations in the detection rates of avian influenza virus (AIV) subtypes H5, H7, and H9 in live poultry in Nanchang city, Chinese province Jiangxi,...
We investigated fluctuations in the detection rates of avian influenza virus (AIV) subtypes H5, H7, and H9 in live poultry in Nanchang city, Chinese province Jiangxi, before and after the Chinese nationwide AIV vaccination campaign against highly pathogenic (HP) AIV subtype H5 and H7. Samples were tested for nucleic acid of type A avian influenza virus by real-time reverse transcription polymerase chain reaction technology. The H5, H7 and H9 subtypes of influenza viruses were further classified for the positive results. Based on the analysis of 2119 samples collected from February 2016 to December 2019, we found that AIV subtypes H5, H7, H9 showed a seasonal pattern, and the positive rate of avian influenza tended to reach its peak in the colder season. The detection rate of AIV subtypes H5, H7, H9 of chickens (39.26%) was significantly higher than that of ducks (5.78%) and pigeons (4.31%). After vaccination, the positive rates of the H5 subtype (0.27%) and the H7 subtype (0.00%) decreased significantly, while the positive rate of the H9 subtype (29.95%) increased significantly. The H9 subtype has become the dominant subtype detected in live poultry and occupies a dominant position in the live bird market. This study showed that the government of China should establish measures for the long-term control of avian influenza.
Topics: Animals; Chickens; China; Influenza A virus; Influenza in Birds; Poultry; Vaccination
PubMed: 34116164
DOI: 10.1016/j.micinf.2021.104848 -
Viruses Sep 2019Understanding virus shedding patterns of avian influenza virus (AIV) in poultry is important for understanding host-pathogen interactions and developing effective... (Meta-Analysis)
Meta-Analysis
Understanding virus shedding patterns of avian influenza virus (AIV) in poultry is important for understanding host-pathogen interactions and developing effective control strategies. Many AIV strains were studied in challenge experiments in poultry, but no study has combined data from those studies to identify general AIV shedding patterns. These systematic review and meta-analysis were performed to summarize qualitative and quantitative information on virus shedding levels and duration for different AIV strains in experimentally infected poultry species. Methods were designed based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Four electronic databases were used to collect literature. A total of 1155 abstract were screened, with 117 studies selected for the qualitative analysis and 71 studies for the meta-analysis. A large heterogeneity in experimental methods was observed and the quantitative analysis showed that experimental variables such as species, virus origin, age, inoculation route and dose, affect virus shedding (mean, peak and duration) for highly pathogenic AIV (HPAIV), low pathogenic AIV (LPAIV) or both. In conclusion, this study highlights the need to standardize experimental procedures, it provides a comprehensive summary of the shedding patterns of AIV strains by infected poultry and identifies the variables that influence the level and duration of AIV shedding.
Topics: Animals; Host-Pathogen Interactions; Influenza A virus; Influenza in Birds; Poultry; Poultry Diseases; Virus Shedding
PubMed: 31480744
DOI: 10.3390/v11090812 -
Archives of Razi Institute Apr 2022Avian Influenza Viruses (AIV) are the causative agents of Avian Influenza (AI), which is a contagious and zoonotic disease in birds. Among birds, wild waterfowls and...
Avian Influenza Viruses (AIV) are the causative agents of Avian Influenza (AI), which is a contagious and zoonotic disease in birds. Among birds, wild waterfowls and ducks are the primary and natural reservoirs of low pathogenic avian influenza viruses (LPAI). This study aimed to identify and differentiate between two AIV subtypes (i.e., hemagglutinin and neuraminidase from domestic ducks by hemagglutinin inhibition (HI) and neuraminidase inhibition (NI) assays. To this end, 962 cloacal swabs were collected from domestic ducks being sold at different Iranian Live Bird Markets in Gilan, Mazandaran, and Golestan provinces, located at the southern coast of the Caspian Sea. The samples were inoculated in 10-day-old embryonated specific pathogen-free chicken eggs, and subsequently, harvested allantoic fluids were subjected to agar gel immunodiffusion, HI, and NI assays. In total, five positive samples, including two H4N2 and three H3N2 AIV subtypes were identified. Isolation of H4N2 and H3N2 viruses has never been reported from Iranian domestic ducks previously. This finding further suggests the diversity of LPAI viruses in Iranian ducks and also shows that the HI and NI assays are highly efficient in determining AIV subtypes.
Topics: Animals; Ducks; Influenza in Birds; Iran; Neuraminidase; Influenza A Virus, H3N2 Subtype; Hemagglutinins; Agar; Phylogeny; Influenza A virus; Chickens
PubMed: 36284964
DOI: 10.22092/ARI.2021.353411.1603