Influenza Virus Molecule

Influenza Virus Strain

Subype
H1N1 A/Beijing/22808/2009 A/Brevig Mission/1/1918 A/Brisbane/59/2007
A/California/04/2009 A/California/07/2009 A/England/195/2009
A/New Caledonia/20/1999 A/New York/18/2009 A/Ohio/07/2009
A/Ohio/UR06-0091/2007 A/Puerto Rico/8/1934 A/Puerto Rico/8/34/Mount Sinai
A/Solomon Islands/3/2006 A/Texas/05/2009 A/WSN/1933
A/USSR/90/1977 A/New York/1/1918 A/Brisbane/59/2007,2008-2009
A/Chile/1/1983 A/Taiwan/01/1986 A/Beijing/262/1995
A/California/06/2009 A/Texas/05/2009     
H1N2 A/swine/Guangxi/13/2006    
H1N3 A/duck/NZL/160/1976    
H1N8 A/Egyptian goose/South Africa/AI1448/2007    
H1N9 A/mallard/Ohio/265/1987    
H2N2 A/Ann Arbor/6/1960 A/Canada/720/2005 A/Japan/305/1957
A/Guiyang/1/1957    
H2N3 A/swine/Missouri/4296424/2006    
H2N8 A/herring gull/DE/703/1988    
H3N1 A/swine/Korea/PZ72-1/2006    
H3N2 A/Babol/36/2005 A/Brisbane/10/2007 A/Perth/16/2009
A/Victoria/210/2009 A/Wisconsin/67/X-161/2005 A/Wyoming/03/2003
A/Aichi/2/1968 A/reassortant/IVR-155 A/Hong Kong/1/1968
A/California/7/2004 A/Memphis/1/68 A/X-31
A/Fujian/411/2002 A/Wisconsin/15/2009 A/Victoria/361/2011
A/Hong Kong/CUHK31987/2011 A/Sydney/5/1997 A/Victoria/208/2009
A/Guangdong-Luohu/1256/2009 A/Moscow/10/1999 A/Texas/50/2012  
H3N8 A/equine/Gansu/7/2008 A/canine/New York/145353/2008  
H4N4 A/mallard duck/Alberta/299/1977    
H4N6 A/mallard/Ohio/657/2002 A/Swine/Ontario/01911-1/99  
H4N8 A/chicken/Alabama/1/1975    
H5N1 A/Anhui/1/2005 A/bar-headed goose/Qinghai/14/2008 A/Cambodia/R0405050/2007
A/Cambodia/S1211394/2008 A/chicken/Egypt/2253-1/2006 A/chicken/India/NIV33487/2006
A/Common magpie/Hong Kong/2256/2006 A/Duck/Hong Kong/p46/97 A/duck/Hunan/795/2002
A/duck/Laos/3295/2006 A/Egypt/2321-NAMRU3/2007 A/Egypt/N05056/2009
A/goose/Guiyang/337/2006 A/Hong kong/213/03 A/Hong Kong/483/97
A/Hubei/2011 A/Indonesia/5/2005 A/Japanese white-eye/Hong Kong/1038/2006
A/turkey/Turkey/1/2005 A/Vietnam/UT31413II/2008 A/whooper swan/Mongolia/244/2005
A/Xinjiang/1/2006 A/Vietnam/1194/2004 A/Vietnam/1203/2004
A/Egypt/3300-NAMRU3/2008 A/Thailand/1 (KAN-1) /2004 A/barnswallow/HongKong/D10-1161/2010
A/chicken/ Yamaguchi/7/2004 A/bar-headed goose/Qinghai/1A/2005 A/chicken/VietNam/NCVD-016/2008
A/common magpie/Hong Kong/5052/2007 A/goose/Guangdong/1/96 A/bar-headed goose/Qinghai/6/2008
A/Hubei/1/2010 A/hubei/2011-CDC A/chicken/Jilin/9/2004    
H5N2 A/American green-winged teal/California/HKWF609/07 A/ostrich/South Africa/AI1091/2006  
H5N3 A/duck/Hokkaido/167/2007    
H5N8 A/duck/NY/191255-59/2002 A/turkey/Ireland/1378/1983  
H5N9 A/chicken/Italy/22A/1998    
H6N1 A/northern shoveler/California/HKWF115/2007    
H6N2 A/duck/Shantou/83/2000    
H6N5 A/shearwater/Australia/1/1973    
H6N4 A/chicken/HongKong/17/77    
H6N8 A/mallard/Ohio/217/1998    
H7N1 A/turkey/Italy/4602/99    
H7N2 A/ruddy turnstone/New Jersey/563/2006    
H7N3 A/chicken/SK/HR-00011/2007 A/turkey/Italy/214845/2002    
H7N7 A/chicken/Netherlands/1/03 A/Netherlands/219/2003 A/equine/Kentucky/1a/1975
H7N8 A/mallard/Netherlands/33/2006    
H7N9 A/Anhui/1/2013 A/Hangzhou/1/2013 A/Pigeon/Shanghai/S1069/2013
A/Shanghai/1/2013 A/Huzhou/10/2013 A/Hangzhou/3/2013  
A/Zhejiang/1/2013 A/Zhejiang/DTID-ZJU10/2013 A/Shanghai/4664T/2013
A/Shanghai/Patient3/2013 A/chicken/Zhejiang/DTID-ZJU01/2013  
H8N4 A/pintail duck/Alberta/114/1979    
H9N2 A/chicken/Hong Kong/G9/1997 A/Guinea fowl/Hong Kong/WF10/99 A/Hong Kong/1073/99
A/Hong Kong/35820/2009 A/duck/Hong Kong/448/78 A/Hong Kong/3239/2008
A/brambling/Beijing/16/2012    
H9N5 A/shorebird/DE/261/2003     
H9N8 A/chicken/Korea/164/04    
H10N3 A/duck/Hong Kong/786/1979 A/duck/Hunan/S11205/2012 A/mallard/Minnesota/Sg-00194/2007  
H10N8 A/Jiangxi-Donghu/346/2013 A/duck/Guangdong/E1/2012    
H10N9 A/duck/HongKong/562/1979    
H11N2 A/duck/Yangzhou/906/2002    
H11N6 A/duck/England/1/1956    
H11N9 A/mallard/Alberta/294/1977    
H12N1 A/mallard duck/Alberta/342/1983    
H12N3 A/bar headed goose/Mongolia/143/2005    
H12N5 A/green-winged teal/ALB/199/1991    
H13N6 A/black-headed gull/Sweden/1/1999    
H13N8 A/black-headed gull/Netherlands/1/00    
H14N5 A/Mallard/Astrakhan(Gurjev)/263/1982    
H15N2 A/Australian shelduck/Western Australia/1756/1983    
H15N8 A/duck/AUS/341/1983    
H16N3 A/black-headed gull/Sweden/5/99    
H17N10 A/little yellow-shouldered bat/Guatemala/164/2009    
H18N11 A/flat-faced bat/Peru/033/2010    
Influenza B B/Brisbane/60/2008 B/Florida/4/2006 B/Malaysia/2506/2004
B/Yamagata/16/1988 B/Massachusetts/03/2010  

Influenza Background Information

Influenza (flu) is a respiratory infection in mammals and birds. It is caused by an RNA virus in the family Orthomyxoviridae. The virus is divided into three main types (Influenza A, Influenza B, and Influenza C), which are distinguished by differences in two major internal proteins (hemagglutinin (HA) and neuraminidase (NA)). Influenza virus type A is found in a wide variety of bird and mammal species and can undergo major shifts in immunological properties. Influenza virus type B is largely confined to humans and is an important cause of morbidity. Little is known about Influenza virus type C, which is not an important source of morbidity.

Influenza A is further divided into subtypes based on differences in the membrane proteins hemagglutinin (HA) and neuraminidase (NA), which are the most important targets for the immune system. The notation HhNn is used to refer to the subtype comprising the hth discovered Hemagglutinin (HA) protein and the nth discovered neuraminidase (NA) protein. The influenza viral Hemagglutinin (HA) protein is a homo trimer with a receptor binding pocket on the globular head of each monomer, and the influenza viral neuraminidase (NA) protein is a tetramer with an enzyme active site on the head of each monomer. Subtypes are further divided into strains; each genetically distinct virus isolate is usually considered to be a separate strain.

Influenza viruses that are known to infect human include the following sub-types. H1N1 virus that caused "Spanish Flu" (A/BrevigMission/1/1918(H1N1)) and seasonal flu (A/Brisbane/59/2007(H1N1), A/New Caledonia/20/1999(H1N1), and A/Solomon Islands/3/2006 (H1N1)) and a reassorted virus (A/California/04/2009(H1N1)) that caused the 2009 swine flu outbreak; H2N2 virus that caused the "Asian Flu"; H3N2 virus that caused the "Hong Kong Flu"; H5N1 "The Bird Flu" virus (A/Anhui/1/2005 (H5N1), A/Vietnam/1203/2004, A/Vietnam/1194/2004 (H5N1), A/bar-headed goose/Qinghai/14/2008 (H5N1), A/turkey/1/2005 (H5N1), A/Indonesia/5/2005 (H5N1)) that was the world's major influenza pandemic threat until the Swine Flu Pandemic of 2009; H7N7 virus that has unusual zoonotic potential; H1N2 is currently endemic in humans and pigs; and H9N2, H7N2, H7N3, H10N7 viruses.

Influenza research involves investigating molecular virology, pathogenesis, host immune responses, genomics, and epidemiology regarding influenza. The main goal of influenza research is to develop influenza countermeasures such as vaccines, therapies and diagnostic tools. Influenza virus vaccination is an effective approach to control influenza virus infection and pandemic spread of the virus. Each seasonal influenza vaccine contains hemagglutinin (HA) and neuraminidase antigen from three influenza subtype viruses-one subtype Influenza A H3N2 virus, one regular seasonal Influenza A H1N1 virus (not the 2009 H1N1 virus), and one Influenza B virus. Because of the influenza virus continues to mutate (antigen minor drifting or antigen major shifting) over time, the viruses in the vaccine change each year based on international surveillance and scientists' estimations about which types and strains of viruses will circulate in a given year. About 2 weeks after vaccination of the influenza viral antigen, antibodies that provide protection against influenza virus infection develop in the body.

Protection mechanism of influenza vaccine is well established to be neutralizing antibody (polyclonal human antibody) raised against influenza viral protein antigen such as the hemagglutinin (HA ) and neuraminidase (NA) protein antigen. Neutralizing antibody can block virus binding to host cells, block viral entry into host cells, and kill infected host cells. Recombinant monoclonal antibody (Mab, mouse monoclonal antibody, rabbit monoclonal antibody, chimeric monoclonal antibody, humanized monoclonal antibody) raised against the hemagglutinin (HA ) antigen or cloned from human B-cells (human monoclonal antibody) have shown to be promising anti-influenza infection product candidates.

At present, there are only three licensed anti-Influenza drugs namely Relenza (Zanamivir - ZMV), Tamiflu (Oseltamivir - OTV) and Amantadine/Rimantadine. The latter targets the M2 ion channel whereas the other compounds target neuraminidase (NA) and were designed through structure-based enzyme inhibitor programmes. Neuraminidase promotes influenza virus release from infected cells and facilitates virus spread within the respiratory tract. The neuraminidase inhibitors interfere with the release of progeny influenza virus from infected host cells, thereby halts the spread of infection in the respiratory tract. The influenza neuraminidase inhibitors are associated with very little toxicity and are far less likely to promote the development of drug-resistant influenza. In addition, the neuraminidase inhibitors are effective against all neuraminidase subtypes and, therefore, against all strains of influenza, a key point in epidemic and pandemic preparedness. Because of a broader antiviral spectrum, better tolerance, and less potential for emergence of resistance than is seen with the M2 inhibitors, the neuraminidase inhibitors represent an important advance in the treatment of influenza.

Please note: All products are "FOR RESEARCH USE ONLY AND ARE NOT INTENDED FOR DIAGNOSTIC OR THERAPEUTIC USE"