Pathogenicity and transmissibility assessment of two strains of human influenza virus isolated in China in 2018

Objective Influenza season occurs every year in China, but its presentation was unusual in the period from December 2017 to early 2018. During this period, influenza activity was increasing across the country and was much greater than during the same period in previous years, with great harm to people’s health. Methods In this study, we isolated two human influenza virus strains—A/Hebei/F076/2018(H1N1) and B/Hebei/16275B/2018—from patients with severe influenza in Hebei, China, during the flu season in January 2018, and explored their genetic characteristics, pathogenicity, and transmissibility. Results A/Hebei/F076/2018(H1N1) belongs to the human-like H1N1 influenza virus lineage, whereas B/Hebei/16275B/2018 belongs to the Victoria lineage and is closely related to the World Health Organization reference strain B/Brisbane/60/2008. Pathogenicity tests revealed that A/Hebei/F076/2018(H1N1) replicated much more strongly in mice, with mice exhibiting 40% mortality, whereas B/Hebei/16275B/2018 was not lethal. Both viruses could be transmitted through direct contact and by the aerosol route between guinea pigs, but the H1N1 strain exhibited higher airborne transmissibility. Conclusions These results may contribute to the monitoring of influenza mutation and the prevention of an influenza outbreak.

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Cacalia hastata L.: anti-influenza activity and phytochemical characteristics of extracts

BIO Web of Conferences ◽

10.1051/bioconf/20213800073 ◽

2021 ◽

Vol 38 ◽

pp. 00073

Author(s):

Irina Lobanova ◽

Ekaterina Filippova ◽

Olga Kotsupiy ◽

Maria Protsenko ◽

Tatiana Kharina ◽

...

Keyword(s):

Influenza Virus ◽

Mixed Forest ◽

Ethanol Extract ◽

Biologically Active ◽

Human Influenza ◽

Human Influenza Virus ◽

Influenza Virus A ◽

Influenza Activity ◽

Neutralization Index

This is the first study to assess antiviral activity against human influenza virus A/Aichi/2/68 and bird influenza virus A/chicken/Kurgan/05/2005 and phytochemical characteristics of an ethanol extract of Cacalia hastata L. from wild populations growing in the vicinity of Tomsk, Russia (mixed forest). A log10 neutralization index—an indicator of inhibition of virus replication by the extract from C. hastata leaves—was ≤2 lg for each influenza virus. The extract reduced the infectivity of the human influenza virus by 1.5-fold and that of the avian influenza virus by 1.7-fold. The phytochemical characterization of C. hastata (its various organs) showed that the largest amount of the tested biologically active substances is present in leaves and rhizomes.

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Antigenic and genetic characteristics of H1N1 human influenza virus isolated from pigs in Japan

Journal of General Virology ◽

10.1099/0022-1317-76-5-1247 ◽

1995 ◽

Vol 76 (5) ◽

pp. 1247-1249 ◽

Cited By ~ 12

Author(s):

K. Katsuda ◽

S. Sato ◽

T. Shirahata ◽

S. Lindstrom ◽

R. Nerome ◽

...

Keyword(s):

Influenza Virus ◽

Human Influenza ◽

Human Influenza Virus ◽

Genetic Characteristics

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Trends of human influenza infection in Chhattisgarh: a retrospective observational study

International Journal of Basic & Clinical Pharmacology ◽

10.18203/2319-2003.ijbcp20192191 ◽

2019 ◽

Vol 8 (6) ◽

pp. 1288

Author(s):

Raj Sharma ◽

Rupendra K. Bharti ◽

Sanat Sharma ◽

Mahendra K. Jaiswal

Keyword(s):

Influenza Virus ◽

Observational Study ◽

Influenza A ◽

Influenza Infection ◽

World Health ◽

Retrospective Observational Study ◽

Human Influenza ◽

Sample Collection ◽

Human Influenza Virus ◽

Significant Difference

Background: Human influenza virus was recognized as a pandemic in 2009 by the World Health Organization (WHO). Since then many newer incidences was recognized in India, but there was no sufficient data from all state of India. This study will provide data from the Chhattisgarh state of India.Methods: It was a retrospective observational study from December 2015 to November 2017. All patient samples with suspected influenza infection were collected and analysed by Real-time reverse polymerase chain reaction (RT-PCR).Results: 341 patients’ sample was collected and analysed; among these samples, 07.9% of patients have all three serotype of influenza positive. Raipur district has the highest incidence of influenza A followed by Durg and Raigarh district of Chhattisgarh. There was no significant difference between male and female who was affected by the influenza virus.Conclusions: The incidence of Human influenza virus is lesser in Chhattisgarh as compare to the average states of India and the state capital has a higher rate of sample collection as well as positive influenza infection.

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Multivalent Sialyllactose-Levan-Conjugated Gold Nanoparticles for Efficient Interaction with and Colorimetric Detection of Influenza A Virus

Chemosensors ◽

10.3390/chemosensors9070186 ◽

2021 ◽

Vol 9 (7) ◽

pp. 186

Author(s):

Sun-Jung Kim ◽

Pan Kee Bae ◽

Yong-Beom Shin

Keyword(s):

Gold Nanoparticles ◽

Influenza Virus ◽

Influenza A Virus ◽

Influenza A ◽

Limit Of Detection ◽

Colorimetric Assay ◽

Colorimetric Detection ◽

H1n1 Influenza ◽

Human Influenza ◽

Human Influenza Virus

We report a colorimetric assay to detect influenza A virus using sialyllactose-levan-conjugated gold nanoparticles (AuNPs). We successfully conjugated 2, 3- and 2, 6-sialyllactose to levan and synthesized sialyllactose-levan-conjugated AuNPs. Each sialyllactose-conjugated levan specifically interacted with a recognizable lectin. Synthesized sialyllactose-conjugated levan acted as reducing and coating agents during the formation of AuNPs. Human influenza A virus specifically bound to 2, 6-sialyllactose-levan-conjugated AuNPs. Moreover, 2, 6-sialyllactose-conjugated levan AuNPs rapidly changed color from red to blue after incubation with human influenza virus. For detecting avian influenza virus, 2, 3-sialyllactose-levan-conjugated AuNPs were more effective than 2, 6-sialyllactose-levan-conjugated AuNPs. Therefore, the efficient targeting and diagnosis of influenza virus according to origin was possible. The deployment of sialyllactose-levan-conjugated particles for the detection of influenza virus is simple and quick. The limit of detection (L.O.D) of H1N1 influenza virus was 7.4 × 103 pfu using 2, 6-siallylactose-levan-conjugated AuNPs and H5N2 influenza virus was 4.2 × 103 pfu using 2, 3-siallylactose-levan- conjugated AuNPs.

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The occurrence of human influenza virus antibodies in the sera of certain wild species of animal

Archives of Virology ◽

10.1007/bf01249965 ◽

1970 ◽

Vol 32 (2-3) ◽

pp. 286-290 ◽

Cited By ~ 2

Author(s):

K. F. Shortridge ◽

G. Belyavin ◽

D. E. Bidwell

Keyword(s):

Influenza Virus ◽

Wild Species ◽

Human Influenza ◽

Human Influenza Virus

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Positive Selection in CD8+T-Cell Epitopes of Influenza Virus Nucleoprotein Revealed by a Comparative Analysis of Human and Swine Viral Lineages

Journal of Virology ◽

10.1128/jvi.01571-15 ◽

2015 ◽

Vol 89 (22) ◽

pp. 11275-11283 ◽

Cited By ~ 27

Author(s):

Heather M. Machkovech ◽

Trevor Bedford ◽

Marc A. Suchard ◽

Jesse D. Bloom

Keyword(s):

T Cells ◽

Influenza Virus ◽

T Cell ◽

Positive Selection ◽

Swine Influenza ◽

Selective Advantage ◽

Influenza Viruses ◽

T Cell Epitopes ◽

Human Influenza ◽

Human Influenza Virus

ABSTRACTNumerous experimental studies have demonstrated that CD8+T cells contribute to immunity against influenza by limiting viral replication. It is therefore surprising that rigorous statistical tests have failed to find evidence of positive selection in the epitopes targeted by CD8+T cells. Here we use a novel computational approach to test for selection in CD8+T-cell epitopes. We define all epitopes in the nucleoprotein (NP) and matrix protein (M1) with experimentally identified human CD8+T-cell responses and then compare the evolution of these epitopes in parallel lineages of human and swine influenza viruses that have been diverging since roughly 1918. We find a significant enrichment of substitutions that alter human CD8+T-cell epitopes in NP of human versus swine influenza virus, consistent with the idea that these epitopes are under positive selection. Furthermore, we show that epitope-altering substitutions in human influenza virus NP are enriched on the trunk versus the branches of the phylogenetic tree, indicating that viruses that acquire these mutations have a selective advantage. However, even in human influenza virus NP, sites in T-cell epitopes evolve more slowly than do nonepitope sites, presumably because these epitopes are under stronger inherent functional constraint. Overall, our work demonstrates that there is clear selection from CD8+T cells in human influenza virus NP and illustrates how comparative analyses of viral lineages from different hosts can identify positive selection that is otherwise obscured by strong functional constraint.IMPORTANCEThere is a strong interest in correlates of anti-influenza immunity that are protective against diverse virus strains. CD8+T cells provide such broad immunity, since they target conserved viral proteins. An important question is whether T-cell immunity is sufficiently strong to drive influenza virus evolution. Although many studies have shown that T cells limit viral replication in animal models and are associated with decreased symptoms in humans, no studies have proven with statistical significance that influenza virus evolves under positive selection to escape T cells. Here we use comparisons of human and swine influenza viruses to rigorously demonstrate that human influenza virus evolves under pressure to fix mutations in the nucleoprotein that promote escape from T cells. We further show that viruses with these mutations have a selective advantage since they are preferentially located on the “trunk” of the phylogenetic tree. Overall, our results show that CD8+T cells targeting nucleoprotein play an important role in shaping influenza virus evolution.

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Human influenza virus A/HongKong/156/97 (H5N1) infection

Vaccine ◽

10.1016/s0264-410x(98)00005-x ◽

1998 ◽

Vol 16 (9-10) ◽

pp. 977-978 ◽

Cited By ~ 96

Author(s):

E CLAAS

Keyword(s):

Influenza Virus ◽

Human Influenza ◽

Human Influenza Virus ◽

Influenza Virus A ◽

H5n1 Infection

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Neuraminidase Activity and Resistance of 2009 Pandemic H1N1 Influenza Virus to Antiviral Activity in Bronchoalveolar Fluid

Journal of Virology ◽

10.1128/jvi.00013-16 ◽

2016 ◽

Vol 90 (9) ◽

pp. 4637-4646 ◽

Cited By ~ 5

Author(s):

Kanyarat Ruangrung ◽

Ornpreya Suptawiwat ◽

Kittipong Maneechotesuwan ◽

Chompunuch Boonarkart ◽

Warunya Chakritbudsabong ◽

...

Keyword(s):

Influenza Virus ◽

Antiviral Activity ◽

H1n1 Virus ◽

H1n1 Influenza ◽

Surfactant Protein D ◽

Pandemic H1n1 ◽

Drug Resistant ◽

Bronchoalveolar Fluid ◽

Influenza Activity ◽

Resistant Strains

ABSTRACTHuman bronchoalveolar fluid is known to have anti-influenza activity. It is believed to be a frontline innate defense against the virus. Several antiviral factors, including surfactant protein D, are believed to contribute to the activity. The 2009 pandemic H1N1 influenza virus was previously shown to be less sensitive to surfactant protein D. Nevertheless, whether different influenza virus strains have different sensitivities to the overall anti-influenza activity of human bronchoalveolar fluid was not known. We compared the sensitivities of 2009 pandemic H1N1, seasonal H1N1, and seasonal H3N2 influenza virus strains to inhibition by human bronchoalveolar lavage (BAL) fluid. The pandemic and seasonal H1N1 strains showed lower sensitivity to human BAL fluid than the H3N2 strains. The BAL fluid anti-influenza activity could be enhanced by oseltamivir, indicating that the viral neuraminidase (NA) activity could provide resistance to the antiviral defense. In accordance with this finding, the BAL fluid anti-influenza activity was found to be sensitive to sialidase. The oseltamivir resistance mutation H275Y rendered the pandemic H1N1 virus but not the seasonal H1N1 virus more sensitive to BAL fluid. Since only the seasonal H1N1 but not the pandemic H1N1 had compensatory mutations that allowed oseltamivir-resistant strains to maintain NA enzymatic activity and transmission fitness, the resistance to BAL fluid of the drug-resistant seasonal H1N1 virus might play a role in viral fitness.IMPORTANCEHuman airway secretion contains anti-influenza activity. Different influenza strains may vary in their susceptibilities to this antiviral activity. Here we show that the 2009 pandemic and seasonal H1N1 influenza viruses were less sensitive to human bronchoalveolar lavage (BAL) fluid than H3N2 seasonal influenza virus. The resistance to the pulmonary innate antiviral activity of the pandemic virus was determined by its neuraminidase (NA) gene, and it was shown that the NA inhibitor resistance mutation H275Y abolished this resistance of the pandemic H1N1 but not the seasonal H1N1 virus, which had compensatory mutations that maintained the fitness of drug-resistant strains. Therefore, the innate respiratory tract defense may be a barrier against NA inhibitor-resistant mutants, and evasion of this defense may play a role in the emergence and spread of drug-resistant strains.

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An Uncertain Risk: The World Health Organization's Account of H1N1

Science in Context ◽

10.1017/s0269889714000167 ◽

2014 ◽

Vol 27 (3) ◽

pp. 511-529 ◽

Cited By ~ 4

Author(s):

Sudeepa Abeysinghe

Keyword(s):

Public Health ◽

Influenza Pandemic ◽

Scientific Evidence ◽

H1n1 Influenza ◽

World Health ◽

Scientific Uncertainty ◽

Global Public Health ◽

The World ◽

Public Risk ◽

Health Organization

ArgumentScientific uncertainty is fundamental to the management of contemporary global risks. In 2009, the World Health Organization (WHO) declared the start of the H1N1 Influenza Pandemic. This declaration signified the risk posed by the spread of the H1N1 virus, and in turn precipitated a range of actions by global public health actors. This article analyzes the WHO's public representation of risk and examines the centrality of scientific uncertainty in the case of H1N1. It argues that the WHO's risk narrative reflected the context of scientific uncertainty in which it was working. The WHO argued that it was attempting to remain faithful to the scientific evidence, and the uncertain nature of the threat. However, as a result, the WHO's public risk narrative was neither consistent nor socially robust, leading to the eventual contestation of the WHO's position by other global public health actors, most notably the Council of Europe. This illustrates both the significance of scientific uncertainty in the investigation of risk, and the difficulty for risk managing institutions in effectively acting in the face of this uncertainty.

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