• In addition, highly pathogenic avian influenza (HPAI) H7N9 viruses emerged that featured a polybasic cleavage site in the hemagglutinin (HA) and were lethal for poultry 7 , 8 . (nature.com)
  • To investigate further which influenza A virus subtype infected these otters, we tested serum samples from these otters by ELISA for antibody-binding activity against 12 recombinant hemagglutinins (rHAs) from 7 influenza A hemagglutinin (HA) subtypes and 2 lineages of influenza B virus ( Technical Appendix Table 1). (cdc.gov)
  • It is an RNA virus categorized into subtypes based on the type of two proteins on the surface of the viral envelope:[citation needed] H = hemagglutinin, a protein that causes red blood cells to agglutinate. (wikipedia.org)
  • citation needed] Different influenza viruses encode for different hemagglutinin and neuraminidase proteins. (wikipedia.org)
  • For example, the H5N1 virus designates an influenza A subtype that has a type 5 hemagglutinin (H) protein and a type 1 neuraminidase (N) protein. (wikipedia.org)
  • The annually updated, trivalent influenza vaccine consists of hemagglutinin (HA) surface glycoprotein components from influenza H3N2, H1N1, and B influenza viruses. (wikipedia.org)
  • The several subtypes are labeled according to an H number (for the type of hemagglutinin) and an N number (for the type of neuraminidase). (wikipedia.org)
  • Single-amino-acid substitution in an antigenic site of influenza virus hemagglutinin can alter the specificity of binding to cell membrane-associated gangliosides. (expasy.org)
  • Structural studies of the parainfluenza virus 5 hemagglutinin-neuraminidase tetramer in complex with its receptor, sialyllactose. (expasy.org)
  • The structure and receptor binding properties of the 1918 influenza hemagglutinin. (expasy.org)
  • Structural basis for receptor specificity of influenza B virus hemagglutinin. (expasy.org)
  • Human infections with avian H7N9 subtype influenza viruses are a major public health concern and vaccines against H7N9 are urgently needed for pandemic preparedness. (nature.com)
  • In early 2013, novel H7N9 influenza viruses emerged in China that caused about 1600 human cases of infection with a high associated case fatality rate. (nature.com)
  • In this study, two H7N9 split virion vaccines with or without AS03 adjuvant were tested in the naive ferret model. (nature.com)
  • In addition, heterologous antibody titers against older H7 subtype viruses of the North American lineage (H7N7, H7N3) and newer H7 subtype viruses of the Eurasian lineage (H7N9) were detected in the animals receiving the AS03-adjuvanted vaccines. (nature.com)
  • In conclusion, this study demonstrated that the AS03-adjuvanted H7N9 vaccines elicited high levels of homologous and heterologous antibodies and protected against H7N9 virus damage post-challenge. (nature.com)
  • In 2013, an avian H7N9 virus strain emerged in China that caused hundreds of human infections. (nature.com)
  • From 2013 to 2017, the H7N9 virus led to annual epidemics. (nature.com)
  • Human infections with H7N9 viruses occurred each year and the viruses gained virulence markers that potentially enhance the risk for humans and may have increased their spread into the human population, making this virus a notable pandemic threat 3 , 4 . (nature.com)
  • During the fifth wave of H7N9 epidemics the virus split into two phylogenetically distinct lineages, the Yangtze River Delta and Pearl River Delta clades 5 . (nature.com)
  • In China, cases of people co-infected with both H7N9 and seasonal influenza virus strains have been reported during the period of overlapping seasonal and H7N9 epidemics 10 . (nature.com)
  • Currently, there is no licensed H7N9 vaccine available and people infected with H7N9 viruses are only treated therapeutically with neuraminidase inhibitors. (nature.com)
  • However, H7N9 is quickly acquiring resistance to neuraminidase inhibitors 13 which is leading to an unreliable public health strategy to combat this virus. (nature.com)
  • Influenza A(H7N9) viruses remain as a high pandemic threat. (bvsalud.org)
  • The continued evolution of the A(H7N9) viruses poses major challenges in pandemic preparedness strategies through vaccination. (bvsalud.org)
  • We assessed the breadth of the heterologous neutralizing antibody responses against the 3rd and 5th wave A(H7N9) viruses using the 1st wave vaccine sera from 4 vaccine groups: 1. (bvsalud.org)
  • The 1st wave vaccines induced robust responses to the 3rd and Pearl River Delta lineage 5th wave viruses but lower cross-reactivity to the highly pathogenic 5th wave A(H7N9) virus. (bvsalud.org)
  • Next-generation vaccines that utilize T cells could potentially overcome the limitations of current influenza vaccines that rely on antibodies to provide narrow subtype-specific protection and are prone to antigenic mismatch with circulating strains. (mdpi.com)
  • This has provided hope for the design of a universal vaccine able to prime against diverse influenza virus strains and subtypes. (mdpi.com)
  • The RSVPreF3-AS01 vaccine, containing the respiratory syncytial virus (RSV) prefusion F protein and the AS01 adjuvant, was previously shown to boost neutralization responses against historical RSV strains and to be efficacious in preventing RSV-associated lower respiratory tract diseases in older adults. (bvsalud.org)
  • The main variants named using this convention are:[citation needed] Bird flu Human flu Swine influenza Equine influenza Canine influenza Bat influenza Variants have also sometimes been named according to their deadliness in poultry, especially chickens:[citation needed] Low pathogenic avian influenza (LPAI) Highly pathogenic avian influenza (HPAI), also called deadly flu or death flu Most known strains are extinct strains. (wikipedia.org)
  • To address this knowledge gap, we measured the levels of virus in ferret nasal washes as well as viral RNA emitted into the air for 14 diverse influenza viruses, encompassing human-, swine-, and avian-origin strains. (cdc.gov)
  • as such, quantification of viral RNA in the air represents a useful addition to established assessments of new influenza virus strains. (cdc.gov)
  • 袁碩峰 Abstract: The rapid mutability of influenza virus in conjunction with genomic reassortment between viral strains promotes the virus' ability to evade vaccines and to become resistant to antiviral drugs. (hku.hk)
  • 200) for rHA of influenza A(H1N1)pdm09 virus (pH1N1) strain A/Texas/05/2009. (cdc.gov)
  • Although none of the 2011 samples showed HI titers to influenza A/duck/New York/96 (H1N1) virus (dk/NY/96) by testing using turkey RBCs ( Technical Appendix Table 2), titers against this strain were detected when using horse RBCs, which is a more sensitive means for the detection of mammalian antibodies against some avian influenza subtypes ( 10 ). (cdc.gov)
  • These results indicate that HI antibodies detected in sea otters are the result of pH1N1 virus infection but cross-react with the avian influenza A(H1N1) virus. (cdc.gov)
  • The intranasal administration of the identified compounds enhanced survival rates and reduced lung viral loads in BALB/c mice infected with H1N1 virus. (hku.hk)
  • [12] Nalika sasi April 2009 sawijining galur virus flu anyar ngalami évolusi kang ngandhut campuran gen saka flu manungsa , babi , lan unggas , kang ing awalé diarani " flu babi " lan uga ditepungi minangka influenza A/H1N1 , kang muncul ing Mèksiko , Amérikah Sarékat , lan sapérangan nagara liya. (wikipedia.org)
  • Histologic findings may include pulmonary changes with alveolar damage similar to seasonal influenza. (medscape.com)
  • Substances elaborated by viruses that have antigenic activity. (lookformedical.com)
  • RSV is divided into two antigenic subtypes, RSV A and RSV B, which is largely based on the variation in the G protein, while the fusion protein F is more conserved and a target for antibody-mediated neutralization. (bvsalud.org)
  • Vaccine group 1 had the highest antibody responses to the vaccine virus and the 3rd/5th wave drifted viruses. (bvsalud.org)
  • Notably, the relative levels of cross-reactivity to the drifted viruses as measured by the antibody GMT ratios to the 5th wave viruses were similar across all 4 vaccine groups. (bvsalud.org)
  • BACKGROUND: One strategy to develop a universal influenza virus vaccine is to redirect the immune system to the highly conserved haemagglutinin stalk domain by sequentially administering vaccines expressing chimeric (c) haemagglutinins with a conserved stalk domain and divergent head domain, to which humans are naive. (bvsalud.org)
  • A filtered and purified influenza A vaccine for humans has been developed and many countries have stockpiled it to allow a quick administration to the population in the event of an avian influenza pandemic. (wikipedia.org)
  • Respiratory syncytial virus (RSV) is a leading cause of severe respiratory disease for which no licensed vaccine is available. (bvsalud.org)
  • These results collectively show that the RSV A-based monovalent Ad26/preF protein vaccine induced neutralizing antibodies, as well as protection against both RSV A and RSV B subtypes in animals, including by passive transfer of human antibodies alone, suggesting that clinical efficacy against both subtypes can be achieved. (bvsalud.org)
  • [15] Vaksin kanggo manungsa kang paling asring dipigunakaké ya iku vaksin influenza trivalen ( trivalent influenza vaccine [TIV]) kang ngandhut antigen kang wis dimurnèkaké lan diinaktivasi marang telung galur virus. (wikipedia.org)
  • Animals receiving two immunizations of the AS03-adjuvanted vaccines were protected from weight loss and fever in the homologous challenge study and had no detectable virus in throat or lung samples. (nature.com)
  • We aimed to assess the reactogenicity, safety, and immunogenicity of adjuvanted and unadjuvanted investigational supra-seasonal universal influenza virus vaccines (SUIVs) in healthy young adults. (bvsalud.org)
  • What is the evidence that influenza vaccines are effective? (lpmhealthcare.com)
  • Here we evaluate the breadth of the protective immune responses across RSV A and RSV B subtypes, induced by vaccines based on the RSV A-based fusion protein, stabilized in the prefusion conformation (preF) in preclinical models. (bvsalud.org)
  • So a flu from a virus similar to the isolate A/Fujian/411/2002(H3N2) is called Fujian flu, human flu, and H3N2 flu. (wikipedia.org)
  • For example, the annual flu subtype H3N2 no longer contains the strain that caused the Hong Kong flu. (wikipedia.org)
  • citation needed] "Contemporary human H3N2 influenza viruses are now endemic in pigs in southern China and can reassort with avian H5N1 viruses in this intermediate host. (wikipedia.org)
  • The sporadic occurrence of human infections with swine-origin influenza A(H3N2) viruses and the continual emergence of novel A(H3N2) viruses in swine herds underscore the necessity for ongoing assessment of the pandemic risk posed by these viruses. (cdc.gov)
  • Here, we selected three recent novel swine-origin A(H3N2) viruses isolated between 2017 to 2020, bearing HAs from the 1990.1, 2010.1 or 2010.2 clades, and evaluated their ability to cause disease and transmit in a ferret model. (cdc.gov)
  • We conclude that despite considerable genetic variances, all three contemporary swine-origin A(H3N2) viruses displayed a capacity for robust replication in the ferret respiratory tract and were also capable of limited airborne transmission. (cdc.gov)
  • Here we show that transmissible viruses display robust replication and fast release into the air. (cdc.gov)
  • In contrast, poorly- and non-transmissible viruses show significantly reduced or delayed replication along with lower detection of airborne viral RNA at early time points post inoculation. (cdc.gov)
  • Galur unggas kang diarani H5N1 wis nimbulaké kakuwatiran munculé pandemi influenza anyar, sawisé kamunculané ing Asia nalika taun 1990-an, nanging virus mau durung évolusi dadi wangun kang nyebar kanthi gampang saka manungsa-menyang-manungsa. (wikipedia.org)
  • Influenza A virus is the only species of the genus Alphainfluenzavirus of the virus family Orthomyxoviridae. (wikipedia.org)
  • Influenza , kang luwih ditepungi kanthi sebutan flu, wujud lelara nular kang disebabaké déning virus RNA saka famili Orthomyxoviridae (virus influenza), kang nyerang unggas lan mamalia . (wikipedia.org)
  • Next, we tested serum samples by using a hemagglutination inhibition (HI) assay with whole influenza virus to detect strain-specific antibodies that inhibit receptor binding. (cdc.gov)
  • No influenza A or B virus-specific HI antibodies were detected in the samples collected during 2001-2002 (data not shown). (cdc.gov)
  • Adsorption with pH1N1, but not dk/NY/96, removed HI antibodies to pH1N1, whereas adsorption with either virus removed HI antibodies against dk/NY/96 ( Technical Appendix Table 4). (cdc.gov)
  • Antibodies to HA neutralize virus. (powershow.com)
  • In addition to seasonally occurring human infections, zoonotic infections caused by avian influenza A viruses are a major public health concern and pose a pandemic threat. (nature.com)
  • Evidence from animal models shows that T cells can provide heterosubtypic protection and are crucial for immune control of influenza virus infections. (mdpi.com)
  • Influenza is one of the most significant causes of acute upper respiratory tract infections worldwide. (medscape.com)
  • Although nasal swab specimens were collected from sea otters in the 2011 study, all specimens were negative for influenza virus by testing in embryonated eggs and by real-time PCR for detection of influenza A viral RNA (data not shown). (cdc.gov)
  • The individual RNPs each contain a binding site for the viral polymerase, as seen by the immunogold labeling of the end of the RNP segment (C). The external view of the virions (D) illustrates the pleomorphic appearance and the surface spikes. (powershow.com)
  • Viral titers in ferret nasal wash specimens and nasal turbinate tissue correlated positively with peak titer in Calu-3 cells, whereas additional phenotypic and molecular determinants of influenza virus virulence and transmissibility in ferrets varied in their association with in vitro viral titer measurements. (cdc.gov)
  • This study underscores the medical importance of polymerase functional domains as druggable targets, which may be due to the fact that these targeted areas are not only highly conserved among virus subtypes but also key to viral fitness. (hku.hk)
  • Importantly, the established screening platforms for PA endonuclease inhibitors, PB2 cap-binding inhibitors, and PA-PB1 interaction disrupters should advance the development of a category of anti-influenza drugs that target viral polymerase. (hku.hk)
  • Humans are immunologically naive to H7 subtype viruses and possess little to no pre-existing, humoral immunity 12 . (nature.com)
  • Influenza A virus (IAV) is a pathogen that causes the flu in birds and some mammals, including humans. (wikipedia.org)
  • Viruses are also transmitted between pigs and humans, and from poultry to humans. (powershow.com)
  • Influenza viruses cause epidemic disease (influenza virus types A and B) and sporadic disease (type C) in humans. (medscape.com)
  • The ability of a pathogenic virus to lie dormant within a cell (latent infection). (lookformedical.com)
  • The neuraminidase, on the other hand, is critical for the subsequent release of the daughter virus particles created within the infected cell so they can spread to other cells. (wikipedia.org)
  • The RNA-dependent RNA polymerase of the virus consists of PA, PB1, and PB2 subunits. (hku.hk)
  • Early alterations of the receptor-binding properties of H1, H2, and H3 avian influenza virus hemagglutinins after their introduction into mammals. (expasy.org)
  • 6-sulfo sialyl Lewis X is the common receptor determinant recognized by H5, H6, H7 and H9 influenza viruses of terrestrial poultry. (expasy.org)
  • Influenza viruses infect millions of people worldwide and result in ~290,000-650,000 influenza-related deaths each year 1 . (nature.com)
  • Influenza B and C are human viruses do not infect birds. (powershow.com)
  • We compiled data from ferrets inoculated with an extensive panel of over 50 human and zoonotic IAV (inclusive of swine-origin and high- and low-pathogenicity avian influenza viruses associated with human infection) under a consistent protocol, with all viruses concurrently tested in a human bronchial epithelial cell line (Calu-3). (cdc.gov)
  • The length of each particle varies considerably, owing to the fact that influenza is pleomorphic, and can be in excess of many tens of micrometers, producing filamentous virions. (wikipedia.org)
  • Of the 30 samples collected during 2011, a total of 22 (73%) showed HI antibody titers of ≥40 against pH1N1 virus. (cdc.gov)
  • However, titers against this strain were on average ≈4-8-fold lower than those for the pH1N1 virus strain, which suggests that that the titers against dk/NY/96 were the result of serologic cross-reactivity with avian- and swine-origin pH1N1 viruses. (cdc.gov)
  • To further test for cross-reactivity, 4 sea otter serum samples were adsorbed with purified pH1N1 and dk/NY/96 virions. (cdc.gov)
  • Rata-rata 41.400 wong mati saben tauné ing Amérikah Sarékat sajeroning kurun wektu antara taun 1979 tekan 2001 amarga influenza. (wikipedia.org)
  • Influenza virus Influenza history Historical records indicate flu-like epidemics throughout recorded history. (powershow.com)
  • Influenza viruses are highly contagious and can cause seasonal epidemics, manifesting as an acute febrile illness with variable degrees of severity, ranging from mild fatigue to respiratory failure and death. (medscape.com)
  • Gangliosides as influenza virus receptors. (expasy.org)
  • Influenza type A viruses are very similar in structure to influenza viruses types B, C, and D. The virus particle (also called the virion) is 80-120 nanometers in diameter such that the smallest virions adopt an elliptical shape. (wikipedia.org)
  • It is an RNA virus whose subtypes have been isolated from wild birds. (wikipedia.org)
  • Occasionally, it is transmitted from wild to domestic birds, and this may cause severe disease, outbreaks, or human influenza pandemics. (wikipedia.org)
  • Wild aquatic birds are the main reservoir of influenza A viruses. (powershow.com)
  • Results of ELISA and hemagglutination inhibition (HI) testing for influenza viruses in serum samples from northern sea otters captured off the coast of Washington, USA, during studies conducted in August 2011. (cdc.gov)
  • Influenza viruses cause a broad array of respiratory illnesses responsible for significant morbidity and mortality in children. (medscape.com)
  • While WA/1 virus exhibited a moderately increased proportion compared to that in the inoculum following co-infection in human respiratory cells, Delta variant possessed a substantial in vivo fitness advantage as this virus becoming predominant in both inoculated and contact animals. (cdc.gov)
  • In addition, an avian H7N2 virus caused an outbreak in cats in an animal shelter in New York that led to one human case 11 . (nature.com)
  • In addition to this human toll, influenza is annually responsible for a total cost of over $10 billion in the U.S." Globally the toll of influenza virus is estimated at 290,000-645,000 deaths annually, exceeding previous estimates. (wikipedia.org)
  • Seasonal human influenza causes about 36,000 deaths and 226,000 hospitalizations in the United States annually. (medscape.com)
  • As influenza A viruses (IAV) continue to cross species barriers and cause human infection, the establishment of risk assessment rubrics has improved pandemic preparedness efforts. (cdc.gov)
  • Influenza viruses display high-affinity binding to human polyglycosylceramides represented on a solid-phase assay surface. (expasy.org)
  • Recently, we reported serologic evidence of influenza A virus infection in free-ranging northern sea otters ( Enhydra lutris kenyoni ) captured off the coast of Washington, USA, in August 2011 ( 8 ). (cdc.gov)
  • We performed bioinformatics analysis on a virus genome from a patient with 2019-nCoV infection and compared it with other related coronavirus genomes. (hku.hk)
  • Specific molecular components of the cell capable of recognizing and interacting with a virus, and which, after binding it, are capable of generating some signal that initiates the chain of events leading to the biological response. (lookformedical.com)
  • See Clinical Presentation for more detailed information on the signs and symptoms of pediatric influenza. (medscape.com)
  • See Clinical Presentation and Workup for more detailed information on the diagnosis of pediatric influenza. (medscape.com)
  • BACKGROUND: Zika virus (ZIKV) may cause severe congenital disease after maternal-fetal transmission. (bvsalud.org)
  • Any of the processes by which cytoplasmic factors influence the differential control of gene action in viruses. (lookformedical.com)