• Highly pathogenic avian influenza A(H5N1) viruses have caused major economic losses in the poultry industry and might cause zoonotic infections. (cdc.gov)
  • Whereas highly pathogenic avian influenza A(H5N1) viruses previously detected in poultry in the Americas are believed to have descended from low pathogenicity viruses in this region ( 5 ), clade 2.3.4.4 viruses were the first highly pathogenic avian influenza virus of the A/goose/Guangdong/1/1996 lineage to appear in North America ( 2 - 4 ) during the winter of 2014-2015. (cdc.gov)
  • In general, highly pathogenic H5 viruses have the N1 subtype (H5N1). (cdc.gov)
  • Examples of different influenza A virus subtypes currently endemic in animals include H1N1 and H3N2 in pigs (different strains than those found in humans), H3N8 in horses, H3N2 in dogs, and H5N1 in wild water birds and domestic poultry. (cdc.gov)
  • More recently, H5N1 viruses from birds have caused sporadic infections in wild foxes in the U.S. and in other countries. (cdc.gov)
  • Highly Pathogenic Avian Influenza A(H5N1) Viruses at the Animal-Human Interface in Vietnam, 2003-2010. (cdc.gov)
  • Scientists have identified a small family of lab-made proteins that neutralize a broad range of influenza A viruses, including the H5N1 avian virus, the 1918 pandemic influenza virus and seasonal H1N1 flu viruses. (science20.com)
  • These human monoclonal antibodies, identical infection-fighting proteins derived from the same cell lineage, also were found to protect mice from illness caused by H5N1 and other influenza A viruses. (science20.com)
  • They scanned tens of billions of monoclonal antibodies produced in bacterial viruses, or bacteriophages, and found 10 antibodies active against the four major strains of H5N1 avian influenza viruses. (science20.com)
  • Since its discovery in the late 1990s, the avian flu virus, or H5N1, has infected at least 100 people, more than half of whom have died. (sourcewatch.org)
  • To date, roughly 103 people have been infected with the H5N1 avian influenza virus--or bird flu. (sourcewatch.org)
  • In addition, these same mutations were required to render highly pathogenic avian influenza viruses of the H5N1 subtype transmissible via the air between ferrets -- a model organism for mammal influenza research. (upi.com)
  • By understanding how viruses like COVID-19 , as well as the H5N1 and H7N9 influenza strains, move from species to species, researchers and health officials can develop more informed strategies for preventing future zoonotic disease outbreaks. (upi.com)
  • Avian influenza (H5N1) is rare in humans in developed countries. (medscape.com)
  • Phylogenetic analysis HA and NA genes showed that they share a common ancestor Qa/HK/G1/97 isolate which had contributed internal genes of H5N1 virus. (scialert.net)
  • On March 29, 2023, Chile reported its first human infection with HPAI A(H5N1) virus. (cdc.gov)
  • The virus was identified as having a clade 2.3.4.4b HA and was determined to be the same genotype that has been detected in the majority of wild birds in South America, indicating no evidence for genetic reassortment compared to A(H5N1) viruses predominating in birds in South America. (cdc.gov)
  • The virus was 99% identical to many viruses identified in A(H5N1) virus-infected wild birds in Chile. (cdc.gov)
  • A highly infectious strain of avian influenza virus (H5N1) has caused multiple outbreaks in domestic poultry and wild birds across Scotland, in other parts of the UK, and internationally. (epicscotland.org)
  • Avian influenza viruses have been around for a very long time, but the Highly Pathogenic Avian Influenza (HPAI) virus strain (H5N1, clade 2.3.4.4b) that has been circulating in birds across much of the globe since 2021 has been the most long-lasting, widespread and severe on record. (epicscotland.org)
  • Research describing two mutant strains of H5N1 avian influenza that spread between mammals is likely to be published in its entirety. (scientificamerican.com)
  • Two teams of scientists, led by Ron Fouchier of Erasmus Medical Center in Rotterdam, the Netherlands, and Yoshihiro Kawaoka of the University of Wisconsin-Madison, have created mutant strains of H5N1 avian influenza. (scientificamerican.com)
  • One particular strain of H5N1, called highly pathogenic avian influenza (HPAI), is responsible for the 'bird flu' scares. (scientificamerican.com)
  • Wild H5N1 viruses cannot latch on tothe cells in a person's nose and throat, but the mutant strains created by Fouchier and Kawaoka can spread between ferrets, which are viewed as a good animal model of flu transmission between humans. (scientificamerican.com)
  • Kawaoka and his team, whose work has been accepted by Nature, created a chimeric virus with the hemagglutinin protein from H5N1 and the genes from the 2009 pandemic strain of H1N1. (scientificamerican.com)
  • Kawaoka notes that H5N1 viruses already circulate in nature, mutate constantly and could cause pandemics. (scientificamerican.com)
  • More practically, the research could allow public-health workers to monitor wild viruses for similar mutations that make H5N1 more dangerous to humans. (scientificamerican.com)
  • This has been fuelled by the report of a parrot infected by the H5N1 strain of avian influenza in the United Kingdom this week. (zetatalk.com)
  • The lack of sustained human-to-human transmission suggests that H5N1 avian virus does not currently have the capacity to cause a human pandemic. (zetatalk.com)
  • In 1997, the H5N1 virus first infected humans during an outbreak among poultry in Hong Kong. (dailynewsegypt.com)
  • This is highlighted by confirmed cases of human infections by highly pathogenic H5N1 viruses, and more recently, the H7N9 outbreak in China [ 5 ]. (springer.com)
  • Similar to H5N1 strains, this further affirms the potential of avian influenza strains capable of directly infecting human, causing severe illnesses. (springer.com)
  • About a decade ago, scientists and public health officials feared that we might be on the brink of a pandemic caused by the so-called avian or bird H5N1 flu that began circulating among poultry, ducks, and geese in Asia and spread to Europe and Africa. (bcm.edu)
  • Unlike the avian H5N1 flu, the H1N1 swine flu is capable of being transmitted easily from person to person. (bcm.edu)
  • Fortunately, however, H1N1 is far less deadly than the H5N1 virus. (bcm.edu)
  • Hopefully, the knowledge gained in response to the H5N1 and 2009 H1N1 outbreaks, and continued research to more completely understand influenza virus, as well as improvements in vaccine and drug development, will enable us to minimize the effects of future influenza outbreaks. (bcm.edu)
  • During 1997, an H5N1 avian influenza virus was determined to be the cause of death in 6 of 18 infected patients in Hong Kong. (mitokor.com)
  • Although it has been known that cleavage site and glycosylation patterns of the HA protein play important roles in determining the pathogenicity of H5 avian influenza viruses, it has only recently been shown that an additional glycosylation site within the globular head of the neuraminidase protein also contributes to the high virulence of the H5N1 virus. (mitokor.com)
  • H5N1 hemagglutinin interacts with cell surface proteins containing oligosaccharides with terminal sialyl residues. (mitokor.com)
  • Virus isolated from a human infected with the H5N1 strain in 1997 could bind to oligosaccharides from human as well as avian sources, indicating its species-jumping ability. (mitokor.com)
  • The World Health Organization is concerned about the highly virulent strains of IAV, such as H5N1 avian viruses which has about 60% lethality rate [ 1 ]. (omicsonline.org)
  • Increasing numbers of confirmed human cases for avian influenza A (H5N1) were reported to WHO between 2003 and 2011. (omicsonline.org)
  • The influenza A H5N1 avian pandemic strain has a mortality rate of nearly 60 percent. (stjude.org)
  • Canadian scientists who have studied big chunks of the genetic code of the two proteins on the surface of the Manitoba H5N1 viruses have confirmed these viruses are from the family of North American H5N1 viruses, not the strains circulating in Southeast Asia. (recombinomics.com)
  • North American H5N1 viruses have so far proven to be much milder viruses than their distant Asian cousins, avian influenza experts say. (recombinomics.com)
  • Emergence of new viruses with clade 2.3.4.4 hemagglutinin (HA) that infect poultry and humans emphasizes the need for detailed characterization of molecular properties of these viruses. (cdc.gov)
  • Flu A viruses are divided into subtypes based on two proteins on the surface of the virus: hemagglutinin (HA) and neuraminidase (NA). (cdc.gov)
  • In 1971, influenza viruses were first classified based on the antigenic properties of their structural and surface proteins: the nucleoprotein (NP) [type] and hemagglutinin (HA) and neuraminidase (NA) [subtype] proteins, as well as the species of origin. (cdc.gov)
  • The reagent was made by reproducing hemagglutinin (HA) protein fragments, which are expressed on the surface of H5 avian influenza virus, through gene recombination and by labeling fluorescent molecules to the fragments. (medicaldesignbriefs.com)
  • The resulting new virus might then be able to infect humans and spread easily from person to person, but it could have surface proteins (hemagglutinin and/or neuraminidase) different than those currently found in influenza viruses that routinely circulate in humans-this could make it seem like a "new" influenza virus to people, one that had not been encountered before. (cdc.gov)
  • The genetic information in these viruses could reassort to create a new influenza A virus with a hemagglutinin and/or neuraminidase gene from the avian virus and other genes from the human virus. (cdc.gov)
  • Influenza A viruses with a hemagglutinin against which humans have little or no immunity that have reassorted with a human influenza virus are more likely to result in sustained human-to-human transmission and have pandemic potential. (cdc.gov)
  • The molecular characterizations of surface proteins hemagglutinin and neuraminidase from recent H5Nx avian influenza viruses. (cdc.gov)
  • Avian influenza viruses (AIV) are classified by a combination of two groups of proteins found on the surface of the virus: hemagglutinin proteins (H), of which there are 18 (H1-H18), and neuraminidase proteins (N), of which there are 11 (N1-N11). (usgs.gov)
  • Ribbon diagram of the influenza virus H5 hemagglutinin (HA) surface protein bound by the F10 monoclonal antibody (red). (science20.com)
  • The hidden part of the influenza virus is in the neck below the peanut-shaped head of the hemagglutinin (HA) protein. (science20.com)
  • The serotype of influenza A virus is determined by the hemagglutinin (HA) and neuraminidase (NA) proteins present on its surface, and there are at least 18 subtypes of HA in influenza A. (scienceboard.net)
  • Unfortunately, the virus is able to escape neutralization by mutating this part of hemagglutinin through a process known as antigenic drift," explained co-author Peter Palese, PhD, professor and chair of the department of microbiology at the Icahn School of Medicine at Mount Sinai. (scienceboard.net)
  • Our chimeric hemagglutinin vaccine is a major advance over conventional vaccines which are often mismatched to the circulating strains of virus, impacting their effectiveness. (scienceboard.net)
  • Comparisons of avian flu strain genomes and mammal-adapted strains revealed changes to the genes responsible for the regulation of hemagglutinin, a protein on the surface of influenza viruses. (upi.com)
  • [7] There are 16 hemagglutinin and 9 neuraminidase subtypes that circulate in a variety of avian species, and a restricted subgroup of these have infected other animals, such as pigs, horses, cats, ferrets, dogs, and marine mammals (seals and whales). (cdc.gov)
  • The hemagglutinin (HA) gene codes for one of the two surface glycoproteins and is central to species specificity because it is responsible for virus attachment and fusion with host cells. (cdc.gov)
  • These viruses are classified according to the identity of two of their surface proteins--hemagglutinin (H5 in this subtype) and neuraminidase (N1). (scientificamerican.com)
  • Two IDV lineages, D/swine/Oklahoma/1334/2011 and D/bovine/Oklahoma/660/2013 (D/660), have been identified in swine and cattle in Europe on the basis of the hemagglutinin-esterase fusion protein (HEF). (cdc.gov)
  • Type A viruses are divided into subtypes based on the nature of their surface proteins: hemagglutinin (H1 to H18) and neuraminidase (N1 to N11). (pasteur.fr)
  • 3.2.1.18) that are found, along with the sialic acid-binding protein Hemagglutinin, on the surface of influenza viruses that are pathogenic to mammalian or avian species. (cazypedia.org)
  • Viruses bind to the cell surface and enter via interaction of the hemagglutinin with cell surface sialic acids. (cazypedia.org)
  • H stands for hemagglutinin, it binds the virus to cells in the respiratory tract, for example. (dailynewsegypt.com)
  • These proteins are called hemagglutinin (HA) and neuraminidase (NA). (bcm.edu)
  • These subtypes are classified based on the combination of the virus coat glycoproteins hemagglutinin (HA) and neuraminidase (NA) subtypes. (mitokor.com)
  • In this thesis we have produced proteins that are densely decorated with carbohydrate determinants in order to study the glycosylation capacity of cell lines (paper I) and generate efficient binders of antibodies (paper II), bacterial toxins (paper III) and virus receptors such as the influenza hemagglutinin (paper IV). (avhandlingar.se)
  • 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)
  • They target and bind tightly to strain-specific regions of hemagglutinin (HA) and neuraminidase (NA) proteins on the virus. (stjude.org)
  • Hemagglutinin (H) is a glycoprotein on the influenza viral surface that allows the virus to bind to cellular sialic acid and fuse with the host cell membrane. (msdmanuals.com)
  • Influenza A viruses are subtyped according to their envelope glycoproteins HA and neuraminidase (NA): 16 HA and 9 NA subtypes are found in aquatic birds and constitute the animal influenza A virus reservoir. (cdc.gov)
  • Viruses with H5 or H7 subtypes occasionally acquire a multibasic cleavage site in their HA ( 8 ), which results in a highly pathogenic phenotype. (cdc.gov)
  • In contrast, the novel highly pathogenic H5 clade 2.3.4.4 viruses have reassorted with different NA subtypes, including N1, N2, N3, N5, N6, and N8 ( 1 , 9 - 17 ). (cdc.gov)
  • Influenza A virus subtypes currently endemic in humans are H3N2 and H1N1 viruses. (cdc.gov)
  • Influenza A viruses can include any one of the 16 known subtypes of HA proteins, which fall into two groups, Group 1 and Group 2. (science20.com)
  • Their monoclonal antibodies neutralized all testable viruses containing the 10 Group 1 HAs-which include the seasonal H1 viruses, the H1 virus that caused the 1918 pandemic and the highly pathogenic avian H5 subtypes-but none of the viruses containing the six Group 2 HAs. (science20.com)
  • The vaccine consists of group 1 or group 2 stalk domains in combination with head domains from avian influenza virus subtypes. (scienceboard.net)
  • Genetically and antigenically, AIV exist as multiple subtypes based on the two glycoproteins (HA and NA) on the virion surface. (scialert.net)
  • A few bat species were recently shown to be infected by influenza viruses originally designated as new influenza A subtypes H17N10 and H18N11. (cdc.gov)
  • The two influenza A virus subtypes have cocirculated in human populations since 1977: influenza A (H1N1) and A (H3N2). (cdc.gov)
  • Influenza B viruses are not divided into subtypes, but are further broken down into 2 lineages: Yamagata and Victoria. (cdc.gov)
  • Influenza viruses are RNA viruses that evolve rapidly, hence the existence of various subtypes and strains. (epicscotland.org)
  • Three influenza A virus (IAV) subtypes circulate globally in swine: H1N1, H1N2 and H3N2. (cdc.gov)
  • In our previous study, three M2e were inserted into the C-terminal of Cap protein of porcine circovirus type 2 (PCV2) to form a universal nanovaccine that protects PCV2 and different subtypes of IAV. (authorea.com)
  • Avian flu outbreaks caused by non-human infecting subtypes occur quite often. (dailynewsegypt.com)
  • Type A influenza is classified into subtypes depending on which versions of two different proteins are present on the surface of the virus. (bcm.edu)
  • The influenza A subtypes are further classified into strains, and the names of the virus strains include the place where the strain was first found and the year of discovery. (bcm.edu)
  • While classification as an LPAI or HPAI virus refers to the severity of disease in infected poultry, both kinds of avian influenza A viruses have caused severe disease in infected humans. (cdc.gov)
  • Influenza A viruses are endemic (can infect and regularly transmit) in 6 animal species or groups (wild waterfowl, domestic poultry, swine, horses, dogs, and bats) in addition to humans. (cdc.gov)
  • However, in 1998, H3N2 viruses from humans were introduced into the pig population and caused widespread disease among pigs. (cdc.gov)
  • Antigenic shift results when a new influenza A virus subtype against which most people have little or no immune protection infects humans. (cdc.gov)
  • While a "shift" of this kind has not occurred in relation to avian influenza viruses, such a "shift" occurred in the spring of 2009 when an H1N1 virus with genes from North American Swine, Eurasian Swine, humans and birds emerged to infect people and quickly spread, causing a pandemic. (cdc.gov)
  • Therefore, careful evaluation of influenza A viruses recovered from humans and animals that are infected with avian influenza A viruses is important to identify genetic reassortment if it occurs. (cdc.gov)
  • Influenza viruses cause epidemic disease (influenza virus types A and B) and sporadic disease (type C) in humans. (medscape.com)
  • But public health officials around the world are warning that the casualty numbers could be much higher if the virus becomes more easily transmittable between humans. (sourcewatch.org)
  • Our chimeric HA vaccine, by contrast, is directed at the proximal part of the HA protein -- the stalk domain -- which has been shown to broadly neutralize diverse influenza virus strains in both animal models and humans. (scienceboard.net)
  • Usually, these occasional introductions of avian influenza viruses in seals, like in humans, are 'dead ends' because the virus is not transmissible from one individual to another," first study author Sander Herfst said in a news release. (upi.com)
  • It is important to monitor and predict which of the various zoonotic viruses have the potential to emerge in humans and start outbreaks or even pandemics," said Herfst. (upi.com)
  • surveillance focused on the subset of avian influenza viruses that pose significant risk of infecting humans, including certain viruses of low pathogenicity in poultry. (nationalacademies.org)
  • With the emergence of non-human H9N2 isolates with avian characteristics, it is important to study the H9N2 isolates from avian hosts in addition to those obtained from humans for pandemic influenza understanding and preparedness. (scialert.net)
  • Birds are the natural hosts for avian influenza viruses therefore infections in humans are uncommon. (epicscotland.org)
  • However, avian influenza viruses may occasionally infect humans: one human case has been reported in the UK since October 2021. (epicscotland.org)
  • It is a subtype of the influenza A virus--the most virulent of the influenza viruses to affect humans. (scientificamerican.com)
  • There are three types of influenza virus in humans, A, B and C. Types A and B are responsible for annual outbreaks. (pasteur.fr)
  • Influenza vaccine development-a high priority for the U.S. military following the deaths of approximately one in every 67 soldiers from the flu during the 1918-1919 pandemic-took a major step forward when researchers at the UK's Medical Research Council were able to isolate the virus (shown at right) from humans. (jnj.com)
  • Influenza A virus (IAV), a deadly zoonotic pathogen, occasionally cross-species transmission among humans, swine and avian. (authorea.com)
  • Three M2e derived from humans, swine and avian IAV were inserted into the C-terminal of the Cap protein to form nanovaccines. (authorea.com)
  • Can bird flu viruses infect humans? (dailynewsegypt.com)
  • Even if the strain does not infect humans, avian flu is can be disastrous: outbreaks kill thousands of animals at a time and impacts the livelihoods of many people, local and national economies and international trade. (dailynewsegypt.com)
  • Majority of influenza A viruses reside and circulate among animal populations, seldom infecting humans due to host range restriction. (springer.com)
  • Yet when some avian strains do acquire the ability to overcome species barrier, they might become adapted to humans, replicating efficiently and causing diseases, leading to potential pandemic. (springer.com)
  • Further understanding and determining host tropism would be important in identifying zoonotic influenza virus strains capable of crossing species barrier and infecting humans. (springer.com)
  • In May the World Health Organisation (WHO) confirmed 26 cases of avian influenza in humans. (cosmosmagazine.com)
  • There are three different types of influenza virus - A, B, and C. Type A viruses infect humans and several types of animals, including birds, pigs, and horses. (bcm.edu)
  • Novel influenza virus strains emerge periodically to which humans have little or no immunity, resulting in devastating pandemics. (mitokor.com)
  • The detection and evaluation of concentration of influenza virus proteins in biological samples is critical in a broad range of medical and biological investigations regarding the concern over potential outbreaks of virulent influenza strains in animals and humans. (omicsonline.org)
  • 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)
  • Humans are immunologically naive to H7 subtype viruses and possess little to no pre-existing, humoral immunity 12 . (nature.com)
  • Even though small clusters of A(H5) virus infections have been reported previously including those involving healthcare workers, current epidemiological and virological evidence suggests that influenza A(H5) viruses have not acquired the ability of sustained transmission among humans, thus the likelihood is low. (who.int)
  • Influenza viruses are considered one of and NA genes of A(H1N1)pdm09 erated with SeqMan DNA Lasergene the most common causes of respira- and H3N2 viruses in Jordan between 7 software (DNASTAR, Madison, tory infection among humans and they March 2010 and March 2013. (who.int)
  • A pandemic occurs when an influenza virus emerges that most people do not have immunity from because it is so different from any previous strain in humans. (who.int)
  • If this new influenza A virus causes illness in people and is transmitted easily from person to person in a sustained manner, an influenza pandemic can occur. (cdc.gov)
  • Each additional case provides the virus an opportunity to improve its ability for human-to-human transmission and develop into a pandemic strain. (sourcewatch.org)
  • An influenza virus vaccine that results in broad immunity would likely protect against any emerging influenza virus subtype or strain and would significantly enhance our pandemic preparedness, avoiding future problems with influenza pandemics as we see them now with COVID-19," said author Florian Krammer, PhD, professor of microbiology at the Icahn School of Medicine at Mount Sinai, in a statement. (scienceboard.net)
  • Without this knowledge we can only apply a reactive rather than a pre-emptive approach to limit the impact of emerging virus infections, as is currently done for the COVID pandemic. (upi.com)
  • Crossing the species barrier to mammals highlights the pandemic potential of H9N2 virus. (scialert.net)
  • In April 2009, a novel influenza A (H1N1) virus, influenza A(H1N1)pdm09-which was different from currently circulating influenza A (H1N1) viruses-emerged and its subsequent spread resulted in the first pandemic of the 21st century. (cdc.gov)
  • The HA is also the primary target of neutralizing antibodies elicited by infection or vaccination, and the HA of virus from this specimen is very closely related (99% identity) to the A/Astrakhan/3212/2020-like pre-pandemic candidate vaccine viruses (e.g. (cdc.gov)
  • Even so, it seems likely that this virus has a greater mortality rate than either ordinary seasonal flu or possibly the 1918 pandemic H1N1 strain . (scientificamerican.com)
  • Fouchier later added, however, that his mutant virus "does not spread yet like a pandemic or seasonal flu virus" and that the ferrets did not die when infected through aerosol transmission. (scientificamerican.com)
  • The extensive media coverage of avian influenza (bird flu) over recent weeks has caused confusion and increasing concern that bird flu will imminently cause a human pandemic. (zetatalk.com)
  • Although minor antigenic drift in the human influenza virus A occurs continuously, a major shift in its surface protein antigens H or N can trigger a worldwide influenza pandemic because of absence of population immunity. (zetatalk.com)
  • While much knowledge regarding the virus has been discovered, we are still no closer to having the ability to predict the next pandemic, such as in the case of 2009 H1N1 pandemic. (springer.com)
  • Every few decades or so, a new version of the influenza virus emerges in the human population that causes a serious global outbreak of disease called a pandemic . (bcm.edu)
  • To date, the avian flu virus has not acquired to ability to spread easily from person to person - a necessary step in order for a virus to cause a pandemic. (bcm.edu)
  • Although the 2009 H1N1 pandemic did not turn out to be as deadly as initially feared, the next pandemic flu virus could emerge at any time, and we must remain vigilant. (bcm.edu)
  • 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 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)
  • Influenza - particularly pandemic strains that emerge periodically as flu viruses mix and form novel strains - remains a global health threat. (stjude.org)
  • Influenza pandemic occurs when a new influenza virus emerges and spreads around the world, and most people do not have immunity. (who.int)
  • and once a pandemic virus has been established, as with the pandemic A(H1N1) in 2009, it can become a seasonal virus. (who.int)
  • For example, until 1998, only H1N1 viruses circulated widely in the U.S. pig population. (cdc.gov)
  • Susceptibility of Brazilian influenza A(H1N1)pdm09 viruses to neuraminidase inhibitors in the 2014-2016 seasons: Identification of strains bearing mutations associated with reduced inhibition profile. (cdc.gov)
  • Reassortment between influenza A (H1N1) and A (H3N2) viruses resulted in the circulation of A (H1N2) virus during the 2001-02 and 2002-03 influenza seasons. (cdc.gov)
  • Subtyping revealed 34 (54.8%) viruses of the H1N1 subtype, comprising 30 (48.4%) H1avN1av viruses, 3 (4.8%) pH1N1av viruses, and 1 (1.6%) H1huN1av virus. (cdc.gov)
  • Fortunately, this happens only rarely-Spanish flu in 1918-9 (H1N1 virus), Asian flu in 1957-8 (H2N2), and Hong Kong flu in 1968-9 (H3N2). (zetatalk.com)
  • The novel virus, commonly called swine flu, is named influenza A (H1N1). (bcm.edu)
  • In only a few short weeks after emerging in North America, the new H1N1 virus reached around the world. (bcm.edu)
  • A(H1N2) variant viruses and one human case of infection with an influenza A(H3N2) variant virus were reported officially.3 One additional human case of infection with an influenza A(H1N1)v virus was detected. (who.int)
  • ABSTRACT Understanding the genetic evolution of A(H1N1)pdm09 and H3N2 viruses can help better select strains to be included in the annual influenza vaccine. (who.int)
  • There is little information on their evolution in Jordan so this study investigated the genetic and antigenic variability of A(H1N1)pdm09 and H3N2 viruses in Jordan by performing phylogenetic and genetic analyses of the HA and NA genes of A(H1N1)pdm09 and H3N2 viruses between 2011 and 2013. (who.int)
  • The full HA and NA genes of 16 H1N1-positive samples obtained in our study and 21 published HA sequences and 20 published NA sequences from Jordanian viruses that were available on online gene databases were analysed. (who.int)
  • Jordanian H1N1 viruses had mutations that are characteristic of antigenic group 6 while H3N2 virus mutations belonged to group 3. (who.int)
  • RÉSUMÉ La compréhension de l'évolution génétique des virus A(H1N1)pdm09 et H3N2 permet de mieux sélectionner les souches devant être ajoutées au vaccin antigrippal annuel. (who.int)
  • Peu de renseignements sont disponibles sur les mutations des virus saisonniers de la grippe A(H1N1)pdm09 et H3N2 en Jordanie. (who.int)
  • Afin de remédier à ce problème et d'étudier les variations génétiques et antigéniques des virus A(H1N1)pdm09 et H3N2, nous avons procédé à des analyses génétiques et phylogénétiques des gènes de l'hémagglutinine (HA) et de la neuraminidase (NA) de ces virus, sur la période 2011-2013 en Jordanie. (who.int)
  • L'analyse a porté sur les séquences complètes des gènes de l'HA et de la NA de 16 échantillons positifs au virus H1N1 prélevés dans le cadre de cette étude, ainsi que sur 21 séquences publiées de l'HA et 20 séquences publiées de la NA, issues de virus jordaniens disponibles sur les bases de données de gènes en ligne. (who.int)
  • Les virus H1N1 jordaniens présentaient des mutations caractéristiques du groupe antigénique 6, tandis que les virus H3N2 appartenaient au groupe 3. (who.int)
  • For the 2016-2017 northern hemisphere influenza season, the vaccine formulation was updated in February 2016 to contain two types, A viruses (H1N1 and H3N2), and a type B virus. (who.int)
  • HA proteins bind to sialoside receptors on the host cell surface. (cdc.gov)
  • Type and number of internal monosaccharides and their linkages determine fine specificity of virus receptors ( 19 , 20 ). (cdc.gov)
  • NA removes sialic acids from glycans, which enables virus particles to be released from the cell surface after assembly and from decoy receptors (e.g., in mucus). (cdc.gov)
  • Although a recent study ( 22 ) reported enhanced avidity of H5N6 viruses for human-type receptors, recombinant clade 2.3.4.4 highly pathogenic influenza A virus H5 proteins from virus isolates in North America show a strict avian receptor-binding preference ( 23 ). (cdc.gov)
  • These viruses use distinct cell surface proteins as receptors to gain entry into avian cells. (elsevierpure.com)
  • As reported in the March 23, 2006, issue of Nature , a team of scientists in the US and Japan , "led by [Virologist] Professor Yoshihiro Kawaoka of the University of Wisconsin at Madison, found that avian influenza viruses and human influenza viruses home in on slightly different receptors. (sourcewatch.org)
  • Researchers found the mutations caused the virus to prefer to attach to mammal virus receptors in the respiratory tract, rather than to avian receptors. (upi.com)
  • Analysis of this HA gene shows that it is closely related to avian A(H5) viruses in HA clade 2.3.4.4b and lacked amino acid changes that improve recognition of mammalian receptors or fusion of the viral membrane with the host endosomal membranes. (cdc.gov)
  • The major role of the NA is to release new progeny virions from an infected cell by enzymatically cleaving sialic acid receptors, which aids virus spread to uninfected cells within an infected host. (cdc.gov)
  • The proliferation of tumor cells is characterized by inflammation of tumor sites, the ability of tumor cells to evolve HSPG (heparan sulphate proteoglycans) in a similar manner to basal membrane Keratinocytes, and the presence of various growth factor receptors known to congregate at the surface of tumor cells. (justia.com)
  • Most bird flu viruses are low pathogenic and cause few or no signs of disease in infected wild birds. (cdc.gov)
  • Directly from infected birds or from avian influenza A virus-contaminated environments. (cdc.gov)
  • People with close or prolonged unprotected contact (not wearing respiratory and eye protection) with infected birds or places that sick birds or their mucous, saliva, or feces have contaminated, might be at greater risk of bird flu virus infection. (cdc.gov)
  • Wild birds, in particular certain species of waterfowl and shorebirds, are considered to be the natural reservoirs for avian influenza viruses. (usgs.gov)
  • In domestic birds, however, some AI viruses can be more pathogenic and mutation or recombination of a virus acquired from wild birds can increase disease potential. (usgs.gov)
  • Most AI strains are classified as low pathogenic avian influenza (LPAI) and cause few clinical signs in infected birds. (usgs.gov)
  • On the other hand, highly pathogenic avian influenza (HPAI) strains frequently fatal to birds and easily transmissible between susceptible species. (usgs.gov)
  • However, AIV also frequently infects domestic poultry and wild ducks in Europe and Africa and migrating wild birds that use the east Atlantic flyway may also risk introducing Eurasian strain viruses to North America via this route. (usgs.gov)
  • AI viruses from both continents, as well as recombinations of both strains, were isolated in Iceland, sometimes from within a single flock of birds, showing that this region is a hotspot of virus movement and genetic reassortment. (usgs.gov)
  • Highly pathogenic AI viruses have been frequently found in wild and domestic European birds, significantly in 2006, and annually since then. (usgs.gov)
  • Since 1997, avian flu strains seem to have infected thousands of birds in 11 countries. (sourcewatch.org)
  • Researchers suspect the 2014 outbreak, which killed some 2,500 seals, began in western Sweden when one or more seals came into contact with infected birds or virus-laden bird droppings. (upi.com)
  • This chapter focuses on the global phenomenon of avian influenza, its impact on the poultry industry, and potential means to control influenza transmission among birds and mammals. (nationalacademies.org)
  • Furthermore, the NA has a full-length stalk which is consistent with viruses that naturally circulate in wild birds. (cdc.gov)
  • All bird keepers are legally required to follow strict biosecurity measures to prevent avian influenza infection in their birds. (epicscotland.org)
  • The latest figures are available for cases in poultry in Scotland , wild birds in GB and non-avian wildlife in GB . (epicscotland.org)
  • Infections in poultry and mass mortalities of wild birds have now (as of February 2023) been reported in several South American countries, including Argentina, which raises further conservation concerns if the virus reaches Antarctica, which could be devastating to the huge seabird colonies there. (epicscotland.org)
  • However, it is rare for strains of avian flu to be transmitted to mammals from birds. (epicscotland.org)
  • The only possible explanation was that birds carrying the virus transmitted it via their faeces to the mink. (biomedcentral.com)
  • Only a few months after the outbreak in Swedish mink, some viruses of the H10N4 subtype were isolated from domestic and wild birds in Great Britain [ 3 ]. (biomedcentral.com)
  • In Great Britain, avian pox in birds of the Paridae family was first diagnosed in a great tit (Parus major) from south-east England in 2006. (ox.ac.uk)
  • Avian influenza - also called bird flu or fowl plague - is a viral disease that infects birds, especially wild geese and ducks. (dailynewsegypt.com)
  • But any influenza A virus may cause bird flu - it only has to adapt itself to birds as a host. (dailynewsegypt.com)
  • With the huge influenza A virus reservoir in wild birds, it is a cause for concern when a new influenza strain emerges with the ability to cross host species barrier, as shown in light of the recent H7N9 outbreak in China. (springer.com)
  • We've got 32 years of surveillance work that says these North American strains in wild birds in the past have never been a threat," Dr. Richard Slemons, an avian influenza expert at Ohio State University, said from Columbus on Saturday. (recombinomics.com)
  • The delay in releasing data was due in part to mixtures of viruses in several birds. (recombinomics.com)
  • The detection of influenza A(H5) virus in nasopharyngeal/oropharyngeal samples collected from individuals in close contact with infected poultry or other birds, whether the individuals are symptomatic or not, is not unexpected. (who.int)
  • Rohrschneider focused initially on cell-surface proteins in cells infected with avian oncorna viruses, identifying the envelope and group-specific antigens (gag proteins). (fredhutch.org)
  • There he worked with Dr. Max D. Cooper (Howard Hughes Medical Institute, National Academy of Sciences) and his research focused on cell surface proteins expressed by preB cells that regulate B cell maturation and homing. (ubc.ca)
  • In addition, he identified a number of novel hematopoietic stem cell surface proteins and began analyzing their function. (ubc.ca)
  • His laboratory has followed two primary interests: 1) the transcription factor networks that regulate fate determination in various cells that make blood, and 2) the cell surface proteins expressed by hematopoietic stem cells that and allow them to communicate with their microenvironment. (ubc.ca)
  • In this regard, his lab has identified a novel family of hematopoietic cell surface proteins, called the CD34 family, and shown that these are essential for a number of developmentally important processes. (ubc.ca)
  • For the new study, published Wednesday in the journal Cell Host and Microbe , researchers exposed ferrets to different strains of H10N7, the virus subtype responsible for the 2014 seal flu outbreak. (upi.com)
  • The outbreak of severe respiratory disease in mink ( Mustela vison) in 1984 was linked to an avian influenza virus of subtype H10N4. (biomedcentral.com)
  • The second most dominant subtype was H1N2 with 27 (43.5%) viruses: 13 (21.0%) H1huN2 viruses, 13 (21.0%) pH1N2 viruses, and 1(1.6%) H1avN2 virus. (cdc.gov)
  • To complicate things even more, there are variants within each subtype, since influenza viruses are permanently evolving and new strains are constantly emerging (this explains why the vaccine changes each year). (pasteur.fr)
  • Virulence and transmission characteristics of clade 2.3.4.4b H5N6 subtype avian influenza viruses possessing different internal gene constellations. (qxmd.com)
  • So, for example, a virus with version 1 of the HA protein and version 2 of the NA protein would be called influenza A subtype H1N2 (A H1N2, for short). (bcm.edu)
  • 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)
  • All human infections caused by a new influenza subtype are required to be reported under the International Health Regulations (IHR, 2005).4 This includes any influenza A virus that has demonstrated the capacity to infect a human and its haemagglutinin gene (or protein) is not a mutated form of those, i.e. (who.int)
  • In Asia, 13 (mostly lethal) cases of human infection with clade 2.3.4.4 H5N6 viruses have been reported ( 7 ). (cdc.gov)
  • Avian influenza is a poultry disease caused by influenza A virus infection. (medicaldesignbriefs.com)
  • Rapid initial response for a suspected infection and continuous surveillance are essential to mitigate the damage from highly pathogenic, transmittable pathogens such as avian influenza viruses. (medicaldesignbriefs.com)
  • Another method involves detecting antibodies produced in the body in reaction to virus infection. (medicaldesignbriefs.com)
  • We have identified the mutations responsible for the block to virus entry in chicken lines resistant to infection by subgroup A ASLVs [ASLV(A)]. The tva genetic locus determines the susceptibility of chicken cells to ASLV(A) viruses. (elsevierpure.com)
  • Influenza is an acute respiratory disease caused by infection with influenza viruses. (cdc.gov)
  • As a result of these antigenic changes, antibodies produced to influenza viruses as a result of infection or vaccination with earlier strains may not be protective against viruses circulating in later years. (cdc.gov)
  • Experimental infection of mink ( Mustela vison) was initially used to link the isolated influenza virus to the clinical symptoms and pathological lesions observed in the field outbreak. (biomedcentral.com)
  • The transportation industry is also adopting similarly rigorous standards to ensure the drivers are healthy and know how to help prevent infection by the COVID-19 virus. (alfafarmers.org)
  • An increasing number of avian pox incidents in Paridae have been reported each year since, indicative of an emergent infection. (ox.ac.uk)
  • Vaccination is the primary intervention used to curb influenza virus infection, and the WHO recommends immunization for at-risk individuals to mitigate disease. (mdpi.com)
  • It is always a great concern when a new flu virus emerges, because the general population does not have immunity and almost everyone is susceptible to infection and disease. (bcm.edu)
  • This virus causes a severe respiratory tract infection in high-risk populations such as elderly people, young children and patients with chronic lung and heart diseases. (omicsonline.org)
  • 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)
  • Respiratory syncytial virus (RSV) is the most frequent cause of lower respiratory tract infection in infants and children and the second most common viral cause of pneumonia in adults. (medscape.com)
  • Influenza pneumonia: Amantadine hydrochloride and rimantadine hydrochloride are approved for the prevention and treatment of influenza A virus infection. (medscape.com)
  • Severe acute respiratory syndrome (SARS) is a serious, potentially life-threatening viral infection caused by a previously unrecognized virus from the Coronaviridae family, the SARS-associated coronavirus (SARS-CoV). (medscape.com)
  • Since the last risk assessment on 21 May 2021, one new laboratory-confirmed human case of influenza A(H5N6) virus infection was reported from China to WHO on 30 May 2021. (who.int)
  • 1. What is the likelihood that additional human cases of infection with avian influenza A(H5) viruses will occur? (who.int)
  • Influenza C virus infection does not cause typical influenza illness and is not discussed here. (msdmanuals.com)
  • H5N8 and H5N2 viruses have caused major economic losses in the poultry industry in Europe and North America, and lethal human infections with H5N6 virus have occurred in Asia. (cdc.gov)
  • The first description of avian influenza (bird flu) dates to 1878 in northern Italy, when it was described as a contagious disease of poultry associated with high mortality, referred to as "fowl plague. (cdc.gov)
  • LPAI viruses also cause either no signs of disease or mild disease in chickens and other domestic poultry. (cdc.gov)
  • In contrast, HPAI viruses can cause severe disease and high mortality in infected poultry yet cause little to no disease signs in certain wild aquatic bird species. (cdc.gov)
  • Highly pathogenic avian influenza outbreaks in domestic poultry cause large economic losses to the U.S. economy. (usgs.gov)
  • While avian influenza is an uncommon disease of poultry in the United States, the U.S. Department of Agriculture (USDA) recognizes the international importance of the disease and has developed considerable animal health policies to detect, prevent, and control avian influenza. (nationalacademies.org)
  • The chapter concludes with an example of a low-pathogen avian influenza outbreak in a group of commercial poultry farms and the steps the industry took to contain further spread of the virus, minimize the risk of exposure, and monitor and prevent further infections. (nationalacademies.org)
  • Avian influenza virus was isolated from poultry farms with history of respiratory illness and increased mortality. (scialert.net)
  • H9N2 viruses circulate widely in the Middle East and are associated with serious disease in poultry. (scialert.net)
  • Avian influenza (bird flu) is a viral disease, and the high pathogenic strains can cause severe disease or death in some poultry and wild bird species. (epicscotland.org)
  • Authorities in southern Germany have discovered the H5N2 bird flu virus on a poultry farm. (dailynewsegypt.com)
  • It can spread easily among domestic poultry like chicken and turkeys and if they contract more serious forms of the virus most animals will die of bird flu. (dailynewsegypt.com)
  • Such cases might occurr in people who had contact with sick or dead poultry that were infected with these viruses. (dailynewsegypt.com)
  • Most human cases were exposed to A(H5) viruses through contact with infected poultry or contaminated environments, including live poultry markets. (who.int)
  • Analysis of the structure and sequence of several different env genes suggests that Env proteins are type 1 fusion machines. (wikipedia.org)
  • The segmented genome allows influenza A viruses from different species to mix genes (reassortment) and create a new virus if influenza A viruses from two different species infect the same person or animal at the same time. (cdc.gov)
  • One possible way that virus reassortment could occur is if a pig were infected with a human influenza A virus and an avian influenza A virus at the same time, the new replicating viruses could reassort and produce a new influenza A virus that had some genes from the human virus and some genes from the avian virus. (cdc.gov)
  • In this study, we characterized HA and NA genes and proteins of 5 Iranian isolate which have been isolated from Commercial broiler chicken in the Iran between 2008 and 2009. (scialert.net)
  • Coupled with previous experimental data and genetic characterization here we tried to investigate the possible influence of different genes on the virulence of these H10 avian influenza viruses in mink. (biomedcentral.com)
  • It was an artificial version of the same process through which wild viruses shuffle their genes, known as reassortment. (scientificamerican.com)
  • A Pyrosequencing-Based Approach to High-Throughput Identification of Influenza A(H3N2) Virus Clades Harboring Antigenic Drift Variants. (cdc.gov)
  • Enhanced genetic characterization of influenza A(H3N2) viruses and vaccine effectiveness by genetic group, 2014-2015. (cdc.gov)
  • We isolated 1 (1.6%) H3N2 virus. (cdc.gov)
  • The most widespread virus in France during the last winter outbreak in 2016-2017 was an A virus (H3N2). (pasteur.fr)
  • Pour le virus H3N2, nous avons généré 20 séquences de l'HA et 19 de la NA, et avons également inclus dans l'analyse 19 séquences publiées de l'HA et 19 de la NA. (who.int)
  • since 1968, most seasonal influenza epidemics have been caused by H3N2 (an influenza A virus). (msdmanuals.com)
  • Avian influenza A viruses are further classified into two categories: highly pathogenic avian influenza (HPAI) and low pathogenic avian influenza (LPAI) A viruses based on specific criteria (viral characteristics and mortality in experimentally infected chickens 1 ). (cdc.gov)
  • Avian influenza is a viral disease caused by various strains of avian influenza viruses that can be classified as low pathogenic avian influenza (LPAI) or highly pathogenic avian influenza (HPAI). (usgs.gov)
  • The USGS National Wildlife Health Center (NWHC) in collaboration with multiple partners conducts research into the ecology of avian influenza virus and surveillance for highly pathogenic avian influenza (HPAI) viruses leading to several significant findings towards early detection and response to HPAI. (usgs.gov)
  • With the on-going European outbreaks of HPAI there is a risk of moving these viruses to North America as well. (usgs.gov)
  • Oct. 7 (UPI) -- Scientists have identified the genetic mutations that allowed an avian flu strain to adapt to mammalian transmission, triggering an outbreak among European seals. (upi.com)
  • A large number of influenza A viruses naturally reside in avian species where they constantly circulate and evolve. (springer.com)
  • Human infections with viruses of animal origin are expected at the human-animal interface wherever these viruses circulate in animals. (who.int)
  • Emergence and intercontinental spread of highly pathogenic avian influenza A(H5Nx) virus clade 2.3.4.4 is unprecedented. (cdc.gov)
  • Scientists conduct blood tests on chickens after an outbreak of avian influenza in China. (cosmosmagazine.com)
  • According to information provided by the U.S. Food and Drug Administration (FDA) on April 17, 2007, "There have not been any human cases of avian influenza in the United States or North America, but there have been cases in other parts of the world such as Asia and Africa . (sourcewatch.org)
  • AI strains are divided into two groups based on the pathogenicity of the virus, or the ability of the virus to produce disease. (usgs.gov)
  • Our study also showed that there are no genetic differences in receptor specificity or the cleavability of the haemagglutinin proteins of these viruses regardless of whether they are of low or high pathogenicity in mink. (biomedcentral.com)
  • In poly I:C stimulated mink lung cells the NS1 protein of influenza A virus showing high pathogenicity in mink down regulated the type I interferon promoter activity to a greater extent than the NS1 protein of the virus showing low pathogenicity in mink. (biomedcentral.com)
  • Differences in pathogenicity and virulence in mink between these strains could be related to clear amino acid differences in the non structural 1 (NS1) protein. (biomedcentral.com)
  • In an effort to better understand the mechanism behind the virulence of influenza A viruses we characterized the complete genome of influenza A viruses that clearly showed different pathogenicity for mink. (biomedcentral.com)
  • PB1-F2 is a small, 90 amino acid long polypeptide expressed in influenza A viruses, which generally exacerbate virus pathogenicity. (omicsonline.org)
  • Knowledge of the evolution of receptor-binding specificity of these viruses, which might affect host range, is urgently needed. (cdc.gov)
  • We report that emergence of these viruses is accompanied by a change in receptor-binding specificity. (cdc.gov)
  • Altered receptor-binding specificity of virus clade 2.3.4.4 H5 proteins might have contributed to emergence and spread of H5Nx viruses. (cdc.gov)
  • Changes in HA receptor-binding properties might affect virus host range and within-host virus properties. (cdc.gov)
  • Type 1 fusion machines initially bind a receptor on the target cell surface, which triggers a conformational change, allowing for binding of the fusion protein. (wikipedia.org)
  • The tropism of the virus is determined by the SU protein domain because it is responsible for the receptor-binding function of the virus. (wikipedia.org)
  • The SU domain therefore determines the specificity of the virus for a single receptor molecule. (wikipedia.org)
  • Exposed on the surface of the viral envelope, the glycoprotein gp120 binds to the CD4 receptor on any target cell that has such a receptor, particularly the helper T-cell. (wikipedia.org)
  • Around this time, Dr. Chuck Sherr at St. Jude's and Dr. Richard Stanley at Albert Einstein identified the normal cellular Fms protein as the cell surface receptor for a growth factor known as the macrophage colony-stimulating factor or M-CSF. (fredhutch.org)
  • This was one of the initial discoveries that mutations in a cell surface receptor could initiate oncogenesis, just one year after the avian erythroblastosis virus oncogene was found to be a mutant EGF receptor. (fredhutch.org)
  • however, the extracellular domain contains a 40-amino-acid, cysteine-rich region that is homologous to the ligand binding region of the low-density lipoprotein receptor (LDLR) proteins. (elsevierpure.com)
  • The virus spike is like a key and the cell's docking point, called a receptor, is like a lock. (sourcewatch.org)
  • Some avian H9 viruses have acquired receptor binding characteristics typical of human strains, increasing the potential for reassortment in both human and pig respiratory tracts ( Suzuki, 2005 ). (scialert.net)
  • The binding of the spike protein with the ace2 receptor (ace2) of the host cell constitutes the first and key step for virus entry. (dranandbabu.com)
  • The coronavirus spike protein just before binding to human cell receptor. (dranandbabu.com)
  • We observed that AGEs activated the receptor for advanced glycation end products (RAGE) on the surface of ECs and consequently upregulated Caveolin-1, which in turn increased caveolae-mediated LDL transcytosis and accelerated AS progression. (bvsalud.org)
  • Carbohydrate - protein inte ractions in nature are often mediated via multivalent binding where the combined strength of multiple receptor - ligand interactions results in a binding that is highly specific and strong. (avhandlingar.se)
  • New research shows that this bird flu currently lacks the protein key to unlock certain cells in the human upper respiratory tract, preventing it from spreading via a sneeze or a cough. (sourcewatch.org)
  • Which viruses cause bird flu? (dailynewsegypt.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)
  • Influenza viruses cause a broad array of respiratory illnesses responsible for significant morbidity and mortality in children. (medscape.com)
  • Severe acute respiratory syndrome corona virus 2 (sars-cov-2) causes. (dranandbabu.com)
  • We use these samples to search for influenza viruses and also systematically for other major respiratory tract viruses, such as respiratory syncytial virus (RSV). (pasteur.fr)
  • Flu, or influenza, is a contagious respiratory illness that spreads from person to person through the air via coughs or sneezes or through contact with infected surfaces. (bcm.edu)
  • Parainfluenza virus (PIV) is second in importance only to RSV as a cause of lower respiratory tract disease in children and pneumonia and bronchiolitis in infants younger than 6 months. (medscape.com)
  • Although respiratory infections can be classified by the causative virus (eg, influenza), they are generally classified. (msdmanuals.com)
  • Influenza refers to illness caused by the influenza viruses, but the term is commonly and incorrectly used to refer to similar illnesses caused by other viral respiratory pathogens. (msdmanuals.com)
  • Influenza is a respiratory virus that can infect the nose, throat and sometimes the lungs. (who.int)
  • It is believed that the intracellular transport of the nascent protein depends, to some extent, on the oligomerization of Env precursors, which allows hydrophobic sequences to be buried inside the protein structure. (wikipedia.org)
  • We characterize the influenza viruses and determine their genome sequences to see how they are evolving and whether they still match the vaccine. (pasteur.fr)
  • The prediction models were trained on influenza protein sequences isolated from both avian and human samples, which were transformed into amino acid physicochemical properties feature vectors. (springer.com)
  • Human influenza viruses, for instance, have so far all been found to have hemagglutanin sequences H1, H2 and H3. (cosmosmagazine.com)
  • In contrast, avian flu viruses have sequences that bind primarily to bird cells. (cosmosmagazine.com)
  • Drift of avian flu sequences? (cdc.gov)
  • North American clade 2.3.4.4 virus isolates have retained only the K222Q substitution but still bind fucosylated sialosides. (cdc.gov)
  • the partners plan to exchange scientific information on avian influenza, share viral isolates, and may eventually manufacture human vaccines against avian viral strains. (nationalacademies.org)
  • The neuraminidase stalks regions in these viruses had no deletion as compared to that A/Dk/HK/ Y280/97 lineage (Ck/Bei-like viruses) and the 2 human isolates A/HK/1073/99, A/HK/1074/99. (scialert.net)
  • By 1980, researchers were using this system to classify influenza viruses regardless of the species of origin. (cdc.gov)
  • Influenza A viruses that typically are endemic in one animal species sometimes can cause illness in another species. (cdc.gov)
  • [8,9] However, these viruses were shown to be incompetent for reassortment with other influenza A viruses, a hallmark of the species, indicating that they are not true influenza A viruses. (cdc.gov)
  • Emergence of a novel avian pox disease in British tit species. (ox.ac.uk)
  • In contrast, sequence variation was evident amongst virus tested from 17 non-Paridae hosts of 5 species. (ox.ac.uk)
  • The ectodomain of matrix protein 2 (M2e) is highly conserved in IAV, and multi-copy M2e from different species are usually displayed on the surface of nanoparticles to improve immunogenicity and constitute universal IAV nanovaccines. (authorea.com)
  • Results showed that the M2e closest to the surface of nanoparticle induced the most efficient protection against IAV derived from corresponding species. (authorea.com)
  • Most influenza A viruses are restricted to their host species, having limited capability to cross species barrier and infect a new host. (springer.com)
  • It has been thought that Eurasian strains of avian influenza viruses enter the United States through the Pacific Flyway (Alaska to Baja California) and that this route is the most likely avenue for emerging Eurasian AIV strains to enter North America. (usgs.gov)
  • This research has demonstrated the importance of the migratory bird flyways in this region to the intercontinental movement of viruses between Europe and North America. (usgs.gov)
  • The Env proteins of the Avian Sarcoma and Leukosis virus (ASLV) and the Murine Leukemia Virus (MLV) are both trimers of SU-TM heterodimers. (wikipedia.org)
  • The isolation of temperature-sensitive transformation-defective mutants of Rous sarcoma virus led to the hypothesis that the viral protein or proteins should be temperature-sensitive in its expression or function, and Dr. John Wyke and Rohrschneider found that expression of some of the cell-surface tumor antigens correlated with transformation, suggesting that they were under control of the transforming gene. (fredhutch.org)
  • The transforming protein of Rous sarcoma virus, Src, had just been identified by Dr. Ray Erikson's group using antibodies from tumor-bearing model organisms. (fredhutch.org)
  • Rohrschneider generated similar antisera and used them to good effect, performing some of the first immunoprecipitation and immunofluorescence experiments to identify the Src protein in Rous sarcoma virus-infected model organisms and to localize the protein to the cytoplasm. (fredhutch.org)
  • He found that adhesion plaques also contained the oncoproteins of Abelson leukemia virus (Abl, now best known at the cause of chronic myelogenous leukemia) and the Susan McDonough and Gardner-Rasheed strains of feline sarcoma virus (Fms and Fgr), while, with colleague Dr. Bob Eisenman, the Myc oncoprotein was found in the nucleus. (fredhutch.org)
  • The subgroup A to E avian sarcoma and leukosis viruses (ASLVs) are highly related and are thought to have evolved from a common ancestor. (elsevierpure.com)
  • December 7, 2020 -- A new universal influenza vaccine has been developed that targets the stalk portion of the influenza virus surface protein rather than the head portion. (scienceboard.net)
  • Therefore, the development of a universal influenza virus vaccine is desirable. (scienceboard.net)
  • The researchers conducted a randomized, multicenter, observer-blind, placebo-controlled phase I clinical trial to evaluate the safety and immunogenicity of the group 1 cHA-based vaccine (a live attenuated or inactive influenza virus vaccine expressing a cH8/1 HA and an N1 NA with a backbone from a master donor stain) in 65 participants in the U.S. (scienceboard.net)
  • Antigenic changes also necessitate frequent updating of influenza vaccine components to ensure that the vaccine is matched to circulating viruses. (cdc.gov)
  • L104M, L115Q, V210A) between the HA of the virus from the Chilean case and A/Astrakhan/3212/2020-like candidate vaccine, and they are not in major antigenic epitopes strongly suggesting that antibodies elicited by the A/Astrakhan/3212/2020-like vaccine would be expected to have good cross-reactivity - and therefore protection - against this virus. (cdc.gov)
  • Each year, the World Health Organization (WHO) recommends which strains should be used to compose the vaccine (three in France and four in other countries) on the basis of the information it receives from the different countries on the viruses circulating there. (pasteur.fr)
  • The team dubbed it the "W.S." virus, and their discovery made it possible to develop a vaccine. (jnj.com)
  • The mucin - type protein was used as a probe to analyze the O - glycosylation capacity of the se cell lines, which today are used for the commercial production of recombinant proteins and vaccine co mponents. (avhandlingar.se)
  • Currently, there is no licensed H7N9 vaccine available and people infected with H7N9 viruses are only treated therapeutically with neuraminidase inhibitors. (nature.com)
  • That approach requires developing and administering a new flu vaccine each year to keep up with changes in those unique and highly variable HA and NA proteins. (stjude.org)
  • Influenza viruses evolve constantly, and twice a year WHO makes recommendations to update the vaccine compositions. (who.int)
  • however, human infections can happen when enough virus gets into a person's eyes, nose, or mouth, or is inhaled. (cdc.gov)
  • Although it is unusual for people to get influenza A virus infections directly from animals, sporadic human infections and outbreaks caused by certain avian influenza A viruses and swine influenza A viruses have been reported. (cdc.gov)
  • Experimental aerosol infections of mink, using mink/84 or chicken/49, were then used to compare in more detail the pathogenesis of the two virus infections [ 8 , 9 ]. (biomedcentral.com)
  • In 2013, an avian H7N9 virus strain emerged in China that caused hundreds of human infections. (nature.com)
  • HA are homotrimeric glycoproteins found on the surface of influenza viruses. (scienceboard.net)
  • Avain Influenza (AI) is a highly contagious disease caused by type A influenza viruses which have negative-sense, single-stranded genomes that encode at least ten proteins including two surface glycoproteins [haemagglutinin (HA) and neuraminidase (NA)], nucleoprotein (NP), three polymerase proteins [polymerase basic (PB1), (PB2) and polymerase acidic (PA)], two matrix (M1 and M2) proteins and two non-structural (NS1 and NS2) proteins. (scialert.net)
  • In contrast to ancestral clade 2.3.4 H5 proteins, novel clade 2.3.4.4 H5 proteins bind to fucosylated sialosides because of substitutions K222Q and S227R, which are unique for highly pathogenic influenza virus H5 proteins. (cdc.gov)
  • Recently, a novel H5 virus (clade 2.3.4.4) has emerged ( 1 - 4 ) and shown unprecedented intercontinental spread. (cdc.gov)
  • These changes might have contributed to the remarkable spread of clade 2.3.4.4 viruses. (cdc.gov)
  • Overall, the genomic analysis of the virus in this specimen does not change CDC's risk assessment related to the avian A(H5) clade 2.3.4.4b viruses. (cdc.gov)
  • Env is a viral gene that encodes the protein forming the viral envelope. (wikipedia.org)
  • The mature product of the env gene is the viral spike protein, which has two main parts: the surface protein (SU) and the transmembrane protein (TM). (wikipedia.org)
  • The env gene codes for the gp160 protein which forms a homotrimer, and is cleaved into gp120 and gp41 by the host cell protease, furin. (wikipedia.org)
  • Influenza A viruses have eight separate gene segments. (cdc.gov)
  • The neuraminidase (NA) gene encodes the other surface protein of the virus. (cdc.gov)
  • The NS gene of mink/84 appears to have contributed to the virulence of the virus in mink by helping the virus evade the innate immune responses. (biomedcentral.com)
  • these processes resulted in multiple genotypes with gene segments of swine, avian, and human origin. (cdc.gov)
  • If it has, they say, it could provide an early warning that the nightmare potential of avian flu is on the brink of being realised. (cosmosmagazine.com)
  • The study suggests avian flu can regularly and repeatedly acquire mutations that make them more transmissible among mammals. (upi.com)
  • These findings suggest that the mutations the avian virus underwent once it took hold within the seal population have allowed it to become transmissible via the air between mammals. (upi.com)
  • Because the strains isolated for the study were collected late in the 2014 outbreak, scientists suggest the mutations may have occurred after the virus was already spreading among seals. (upi.com)
  • The genome of the airborne strain differed from the original one by just five mutations, which have all been spotted individually in wild viruses. (scientificamerican.com)
  • Nevertheless, the scientists recommend checking future laboratory-confirmed human avian flu cases to see if any such mutations have occurred in the virus's hemagglutanin coating. (cosmosmagazine.com)
  • Les mutations individuelles sont décrites en détail. (who.int)
  • Further characterization of the virus from the patient is planned. (who.int)
  • It is also possible that the process of genetic reassortment could occur in a person who is co-infected with an avian influenza A virus and a human influenza A virus. (cdc.gov)
  • In lungs of infected mice, the influenza virus structural nucleoprotein NP was detected in parallel using a specific anti-NP antibody. (omicsonline.org)
  • Cellular immune responses against highly conserved Influenza A virus antigens, such as nucleoprotein (NP) and matrix protein-1 (M1), have previously been shown to be associated with protection from disease, whilst viral-vectored vaccines are an effective strategy to boost cell-mediated immunity. (ox.ac.uk)
  • Drug Susceptibility Evaluation of an Influenza A(H7N9) Virus by Analyzing Recombinant Neuraminidase Proteins. (cdc.gov)
  • Key to their research, Dr. Marasco and his colleagues discovered and described the atomic structure of an obscure but genetically stable region of the influenza virus to which their monoclonal antibodies bind. (science20.com)
  • To penetrate a cell, the spikes that stud an influenza virus have to be able to bind to the cellular surface. (sourcewatch.org)
  • The group also developed a reagent to detect anti-H5 avian influenza virus antibody, a fluorescein-labeled protein that binds only with the antibody. (medicaldesignbriefs.com)
  • The scientists also identified a new mechanism of antibody action against influenza: Once the antibody binds, the virus cannot change its shape, a step required before it can fuse with and enter the cell it is attempting to infect. (science20.com)
  • Detection of oseltamivir-resistant zoonotic and animal influenza A viruses using the rapid influenza antiviral resistance test. (cdc.gov)
  • When used together as a host tropism prediction system, zoonotic strains could potentially be identified based on different protein prediction results. (springer.com)
  • Swine influenza virus. (medscape.com)
  • During 2019–2021, we isolated 62 swine influenza A viruses in Belgium and the Netherlands. (cdc.gov)
  • From those samples, we obtained 62 swine IAVs by virus isolation in MDCK cells. (cdc.gov)
  • Viruses that have caused past pandemics typically originated from animal influenza viruses. (who.int)
  • These laboratory strains could be passed between mammals more easily than wild strains of the virus. (scientificamerican.com)
  • Carbohydrates are ubiquitous on the surface of all cells in mammals where they are involved in interactions with the surroundings (extracellular matrix), other cells (including self and non - self) and microbes (bacteria and virus). (avhandlingar.se)
  • Encouraged by these findings, they collaborated with Ruben O. Donis, Ph.D., of the CDC Influenza Division, and found that three of these monoclonal antibodies had broader neutralization capabilities when tested in cell cultures and in mice against representative strains of other known influenza A viruses. (science20.com)
  • This parallel detection of PB1-F2 and NP suggests that applied sensor chip technology may be amenable to an arrow immunosensor for simultaneous detection of all known influenza virus proteins in infected tissues and cells. (omicsonline.org)
  • The overall public health risk from currently known influenza viruses at the human-animal interface has not changed, and the likelihood of sustained human-to-human transmission of these viruses remains low. (who.int)
  • Flu viruses change all the time due to antigenic drift, but antigenic shift happens less frequently. (cdc.gov)
  • Influenza A and B viruses both undergo gradual, continuous change in the HA and NA proteins, known as antigenic drift. (cdc.gov)
  • That's why many virus types are considered "highly pathogenic. (dailynewsegypt.com)
  • This study also advanced understanding of the role a protein named mTOR plays in generating the highly specific antibodies. (stjude.org)
  • Global update on the susceptibilities of human influenza viruses to neuraminidase inhibitors and the cap-dependent endonuclease inhibitor baloxavir, 2017-2018. (cdc.gov)
  • Influenza viruses can be divided into 4 types: A, B, C, and D. Influenza type C viruses are not associated with severe disease, epidemics, or pandemics, and influenza D viruses primarily affect cattle and are not known to infect or cause illness in people, so neither will be discussed further here. (cdc.gov)
  • Above the usual measures put in place for the prevention, surveillance, and reporting of avian influenza, additional investigations are being conducted in wild and domestic bird populations to identify why this outbreak has been more severe than previous outbreaks. (epicscotland.org)
  • The unique property of some avian H10 viruses, particularly the ability to cause severe disease in mink without prior adaptation, enabled our study. (biomedcentral.com)
  • Hospitals also send us influenza virus strains from severe cases or treatment failures so that we can analyze their sensitivity to antiviral drugs. (pasteur.fr)
  • Influenza B viruses may cause milder disease but often cause epidemics with moderate or severe disease, either as the predominant circulating virus or along with influenza A. (msdmanuals.com)
  • Antiviral drugs for influenza can reduce severe complications and deaths although influenza viruses can develop resistance to the drugs. (who.int)
  • The balance between activities of HA and NA proteins has a critical role in optimal viral fitness, tropism, and transmission ( 21 ). (cdc.gov)
  • Colorized transmission electron micrograph (37,800X) of the A/New Jersey/76 (Hsw1N1) virus under plate magnification. (medscape.com)
  • Close contacts of the patient have been asymptomatic and have tested negative for influenza viruses, indicating that no known human-to-human transmission occurred ( 2 ). (cdc.gov)
  • Understanding and predicting host tropism of influenza proteins lay an important foundation for future work in constructing computation models capable of directly predicting interspecies transmission of influenza viruses. (springer.com)
  • At present, few cases of human-to-human H7N9 transmission have ever been recorded, and the position of the WHO authorities is that the virus is currently incapable of sustained transmission between people. (cosmosmagazine.com)
  • There was some evidence of human to human spread of this virus, but it is thought that the transmission efficiency was fairly low. (mitokor.com)
  • 2. What is the likelihood of human-to-human transmission of avian influenza A(H5) viruses? (who.int)
  • To address the threat that avian influenza (AI) poses to human health, it is necessary to recognize its broader agricultural and economic implications and to integrate this knowledge into disease control strategies. (nationalacademies.org)
  • Description: Influenza A virus is a major public health threat, killing more than 30,000 people per year in the USA. (mitokor.com)
  • Here, we utilise a database of opportunistic reports of garden bird mortality and morbidity to analyse spatial and temporal patterns of suspected avian pox throughout Great Britain, 2006-2010. (ox.ac.uk)
  • Influenza-virus-mediated disease can be associated with high levels of morbidity and mortality, particularly in younger children and older adults. (mdpi.com)
  • Avian pox is a viral disease with a wide host range. (ox.ac.uk)
  • There are four classes of influenza viruses (A-D), with influenza A and B causing most seasonal epidemics. (scienceboard.net)
  • This genetic change, or shift, in the virus results in immunity to only specific strains of the influenza virus, requiring frequent re-formulation and re-administration of seasonal vaccines. (scienceboard.net)
  • To tackle these seasonal outbreaks, detailed surveillance mechanisms have been introduced at national and international level, making influenza viruses the most closely monitored viruses on the planet (see Interview below). (pasteur.fr)
  • Every year, seasonal Influenza A virus (IAV) affects millions of people leading to illness and death. (omicsonline.org)
  • 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)
  • The efficacy of currently available seasonal influenza vaccines targeting polymorphic surface antigens has historically been suboptimal. (ox.ac.uk)
  • Seasonal influenza (or "flu") is most often caused by type A or B influenza viruses. (who.int)
  • Seasonal influenza outbreaks are caused by small changes in viruses that have already circulated, and to which many people have some immunity. (who.int)