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H5N1
Influenza A virus subtype H5N1 (A/H5N1) is a subtype of the influenza A virus, which causes the disease avian influenza (often referred to as "bird flu"). It is enzootic (maintained in the population) in many bird populations, and also panzootic (affecting animals of many species over a wide area). A/H5N1 virus can also infect mammals (including humans) that have been exposed to infected birds; in these cases, symptoms are frequently severe or fatal. A/H5N1 virus is shed in the saliva, mucus, and feces of infected birds; other infected animals may shed bird flu viruses in respiratory secretions and other body fluids (such as milk). The virus can spread rapidly through poultry flocks and among wild birds. An estimated half billion farmed birds have been slaughtered in efforts to contain the virus. Symptoms of A/H5N1 influenza vary according to both the strain of virus underlying the infection and on the species of bird or mammal affected. Classification as either Low Pathogeni ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
A/Fujian (H5N1)
: ''See Influenza for details about the illnesses and Influenza A virus subtype H5N1 and Influenza A virus subtype H3N2 for details about the causative agents.'' Fujian flu refers to flu caused by either a Fujian human flu strain of the H3N2 subtype of the ''Influenza A virus'' or a Fujian bird flu strain of the H5N1 subtype of the ''Influenza A virus''. These strains are named after Fujian, a coastal province in Southeast China. A/Fujian (H3N2) human flu (from A/Fujian/411/2002(H3N2) -like flu virus strains) caused an unusually severe 2003–2004 flu season. This was due to a reassortment event that caused a minor clade to provide a haemagglutinin gene that later became part of the dominant strain in the 2002–2003 flu season. A/Fujian (H3N2) was made part of the trivalent influenza vaccine for the 2004-2005 flu season and its descendants are still the most common human H3N2 strain. A/Fujian (H5N1) bird flu is notable for its resistance to standard medical countermea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Avian Influenza
Avian influenza, also known as avian flu or bird flu, is a disease caused by the influenza A virus, which primarily affects birds but can sometimes affect mammals including humans. Wild aquatic birds are the primary host of the influenza A virus, which is enzootic (continually present) in many bird populations. Symptoms of avian influenza vary according to both the strain of virus underlying the infection, and on the species of bird or mammal affected. Classification of a virus strain as either low pathogenic avian influenza (LPAI) or high pathogenic avian influenza (HPAI) is based on the severity of symptoms in domestic chickens and does not predict severity of symptoms in other species. Chickens infected with LPAI display mild symptoms or are asymptomatic, whereas HPAI causes serious breathing difficulties, significant drop in egg production, and sudden death. Domestic poultry may potentially be protected from specific strains of the virus by vaccination. Humans and other ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Goose Guangdong Virus
The Goose Guangdong virus refers to the strain A/Goose/Guangdong/1/96 (Gs/Gd)-like H5N1 HPAI viruses. It is a strain of the Influenzavirus A subtype H5N1 virus that was first detected in a goose in Guangdong in 1996. It is an HPAI (High Pathogenic Avian Influenza) virus, meaning that it can kill a very high percentage of chickens in a flock in mere days. It is believed to be the immediate precursor of the current dominant strain of HPAI A(H5N1) that evolved from 1999 to 2002 creating the Z genotype (also called "Asian lineage HPAI A(H5N1)") that is spreading globally and is epizootic (an epidemic in nonhumans) and panzootic (affecting animals of many species, especially over a wide area), killing tens of millions of birds and spurring the culling of hundreds of millions of others to stem its spread.98%) nucleotide homology to the human influenza virus A/Hong Kong/156/97 (H5N1) in the six internal genes. The N1 neuraminidase sequence showed 97% nucleotide homology to that of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Influenzavirus A
''Influenza A virus'' (''Alphainfluenzavirus influenzae'') or IAV is the only species of the genus ''Alphainfluenzavirus'' of the virus family '' Orthomyxoviridae''. It is a pathogen with strains that infect birds and some mammals, as well as causing seasonal flu in humans. Mammals in which different strains of IAV circulate with sustained transmission are bats, pigs, horses and dogs; other mammals can occasionally become infected. IAV is an enveloped negative-sense RNA virus, with a segmented genome. Through a combination of mutation and genetic reassortment the virus can evolve to acquire new characteristics, enabling it to evade host immunity and occasionally to jump from one species of host to another. Subtypes of IAV are defined by the combination of the antigenic H and N proteins in the viral envelope; for example, " H1N1" designates an IAV subtype that has a type-1 hemagglutinin (H) protein and a type-1 neuraminidase (N) protein. Almost all possible combinations of H ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Panzootic
A panzootic (from Greek παν all + ζόιον animal) is an epizootic (an outbreak of an infectious disease of non-human animals) that spreads across a large region (for example a continent), or even worldwide. The equivalent in human populations is called a pandemic. A panzootic can start when three conditions have been met: * the emergence of a disease new to the population. * the agent infects a species and causes serious illness. * the agent spreads easily and sustainably among animals. A disease or condition is not a panzootic merely because it is widespread or kills a large number of animals; it must also be infectious. For example, cancer is responsible for a large number of deaths but is not considered a panzootic because the disease is, generally speaking, not infectious. Unlike an epizootic, a panzootic covers all or nearly all species over a large surface area (ex. rabies, anthrax). Typically an enzootic or an epizootic, or their cause, may act as a potential prepa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hemagglutinin (influenza)
Influenza hemagglutinin (HA) or haemagglutinin#Notes, [p] (British English) is a homotrimeric glycoprotein found on the surface of influenza viruses and is integral to its infectivity. Hemagglutinin is a class I fusion protein, having multifunctional activity as both an attachment factor and membrane fusion protein. Therefore, HA is responsible for binding influenza viruses to sialic acid on the Cell membrane, surface of target cells, such as cells in the Respiratory tract, upper respiratory tract or erythrocytes, resulting in the Receptor-mediated endocytosis, internalization of the virus. Additionally, HA is responsible for the fusion of the viral envelope with the late endosome, endosomal membrane once exposed to low pH (5.0–5.5). The name "hemagglutinin" comes from the protein's ability to cause red blood cells (i.e., erythrocytes) to clump together (i.e., Agglutination (biology), agglutinate) ''in vitro''. Subtypes Hemagglutinin (HA) in influenza A virus (IAV) has at lea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Influenza A Virus Subtype H7N9
Influenza A virus subtype H7N9 (A/H7N9) is a subtype of the influenza A virus, which causes influenza (flu), predominantly in birds. It is enzootic (maintained in the population) in many bird populations. The virus can spread rapidly through poultry flocks and among wild birds; it can also infect humans that have been exposed to infected birds. A/H7N9 virus is shed in the saliva, mucus, and feces of infected birds; other infected animals may shed bird flu viruses in respiratory secretions and other body fluids. Symptoms of A/H7N9 influenza vary according to both the strain of virus underlying the infection and on the species of bird or mammal affected. Classification as either Low Pathogenic Avian Influenza (LPAI) or High Pathogenic Avian Influenza (HPAI) is based on the severity of symptoms in domestic chickens and does not predict the severity of symptoms in humans. Chickens infected with LPAI A/H7N9 virus display mild symptoms or are asymptomatic, whereas HPAI A/H7N9 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Viral Neuraminidase
Viral neuraminidase is a type of neuraminidase found on the surface of influenza viruses that enables the virus to be released from the host cell. Neuraminidases are enzymes that cleave sialic acid (also called neuraminic acid) groups from glycoproteins. Viral neuraminidase was discovered by Alfred Gottschalk (biochemist), Alfred Gottschalk at the WEHI, Walter and Eliza Hall Institute in 1957. Neuraminidase inhibitors are antiviral agents that inhibit influenza viral neuraminidase activity and are of major importance in the control of influenza. Viral neuraminidases are the members of the glycoside hydrolase family 3CAZY GH_34which comprises enzymes with only one known activity; sialidase or neuraminidase . Neuraminidases cleave the terminal sialic acid residues from carbohydrate chains in glycoproteins. Sialic acid is a negatively charged sugar associated with the protein and lipid portions of lipoproteins. To infect a host cell, the influenza virus attaches to the exteri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
RNA Virus
An RNA virus is a virus characterized by a ribonucleic acid (RNA) based genome. The genome can be single-stranded RNA (ssRNA) or double-stranded (Double-stranded RNA, dsRNA). Notable human diseases caused by RNA viruses include influenza, SARS, MERS, COVID-19, Dengue virus, hepatitis C, hepatitis E, West Nile fever, Ebola virus disease, rabies, polio, mumps, and measles. All known RNA viruses, that is viruses that use a homologous RNA-dependent polymerase for replication, are categorized by the International Committee on Taxonomy of Viruses (ICTV) into the realm ''Riboviria''. This includes RNA viruses belonging to ''Group III'', ''Group IV'' or ''Group V'' of the Virus classification#Baltimore classification, Baltimore classification system as well as ''Group VI. Group VI'' viruses are retroviruses, viruses with RNA genetic material that use DNA intermediates in their Viral life cycle, life cycle including HIV-1 and HIV-2 which cause AIDS. The majority of such RNA viruses fall ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Centers For Disease Control
The Centers for Disease Control and Prevention (CDC) is the national public health agency of the United States. It is a United States federal agency under the Department of Health and Human Services (HHS), and is headquartered in Atlanta, Georgia. The CDC's current nominee for director is Susan Monarez. She became acting director on January 23, 2025, but stepped down on March 24, 2025 when nominated for the director position. On May 14, 2025, Robert F. Kennedy Jr. stated that lawyer Matthew Buzzelli is acting CDC director. However, the CDC web site does not state the acting director's name. The agency's main goal is the protection of public health and safety through the control and prevention of disease, injury, and disability in the US and worldwide. The CDC focuses national attention on developing and applying disease control and prevention. It especially focuses its attention on infectious disease, Foodborne illness, food borne pathogens, environmental health, occupat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
