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Up to new tricks – A review of cross-species transmission of influenza A viruses

  • Gabriele A. Landolt (a1) and Christopher W. Olsen (a2)


Influenza is a highly contagious disease that has burdened both humans and animals since ancient times. In humans, the most dramatic consequences of influenza are associated with periodically occurring pandemics. Pandemics require the emergence of an antigenically novel virus to which the majority of the population lacks protective immunity. Historically, influenza A viruses from animals have contributed to the generation of human pandemic viruses and they may do so again in the future. It is, therefore, critical to understand the epidemiological and molecular mechanisms that allow influenza A viruses to cross species barriers. This review summarizes the current knowledge of influenza ecology, and the viral factors that are thought to determine influenza A virus species specificity.


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Abe, Y, Takashita, E, Sugawara, K, Matsuzaki, Y, Muraki, Y and Hongo, S (2004). Effect of the addition of oligosaccharides on the biological activities and antigenicity of influenza A/H3N2 virus hemagglutinin. Journal of Virology 78: 96059611.
Abed, Y, Bourgault, AM, Fenton, RJ, Morley, PJ, Gower, D, Owens, IJ, Tisdale, M and Boivin, G (2002). Characterization of 2 influenza A (H3N2) clinical isolates with reduced susceptibility to neuraminidase inhibitors due to mutations in the hemagglutinin gene. Journal of Infectious Diseases 186: 10741080.
Acland, HM, Silverman, Bachin LA and Eckroade, RJ (1984). Lesions in broiler and layer chickens in an outbreak of highly pathogenic avian influenza virus infection. Veterinary Pathology 21: 564569.
Ado, AD and Titova, SM (1959). Studies on experimental influenza in dogs. Voprosy Virusologii 4: 165169.
Air, GM and Laver, WG (1989). The neuraminidase of influenza virus. Proteins 6: 341356.
Alexander, DJ and Brown, IH (2000). Recent zoonoses caused by influenza A viruses. Revue Scientifique et Technique 19: 197225.
Amonsin, A, Payungporn, S, Theamboonlers, A, Thanawongnuwech, R, Suradhat, S, Pariyothorn, N, Tantilertcharoen, R, Damrongwantanapokin, S, Buranathai, C, Chaisingh, A, Songserm, T and Poovorawan, Y (2006). Genetic characterization of H5N1 influenza A viruses isolated from zoo tigers in Thailand. Virology 344: 480491.
Ayora-Talavera, G, Cadavieco-Burgos, JM and Canul-Armas, AB (2005). Serologic evidence of human and swine influenza in Mayan persons. Emerging Infectious Diseases 11: 158161.
Aytay, S and Schulze, IT (1991). Single amino acid substitutions in the hemagglutinin can alter the host range and receptor binding properties of H1 strains of influenza A virus. Journal of Virology 65: 30223028.
Baigent, SJ and McCauley, JW (2001). Glycosylation of haemagglutinin and stalk-length of neuraminidase combine to regulate the growth of avian influenza viruses in tissue culture. Virus Research 79: 177185.
Baigent, SJ and McCauley, JW (2003). Influenza type A in humans, mammals and birds: determinants of virus virulence, host-range and interspecies transmission. BioEssays 25: 657671.
Baigent, SJ, Bethell, RC and McCauley, JW (1999). Genetic analysis reveals that both haemagglutinin and neuraminidase determine the sensitivity of naturally occurring avian influenza viruses to zanamivir in vitro. Virology 263: 323338.
Banks, J and Plowright, L (2003). Additional glycosylation at the receptor binding site of the hemagglutinin (HA) for H5 and H7 viruses may be an adaptation to poultry hosts, but does it influence pathogenicity? Avian Diseases 47: 942950.
Baum, LG and Paulson, JC (1991). The N2 neuraminidase of human influenza virus has acquired a substrate specificity complementary to the hemagglutinin receptor specificity. Virology 180: 1015.
Bean, WJ, Schell, M, Katz, J, Kawaoka, Y, Naeve, C, Gorman, O and Webster, RG (1992). Evolution of the H3 influenza virus hemagglutinin from human and nonhuman hosts. Journal of Virology 66: 11291138.
Beare, AS and Webster, RG (1991). Replication of avian influenza viruses in humans. Archives of Virology 119: 3742.
Belshe, RB (2005). The origins of pandemic influenza–lessons from the 1918 virus. New England Journal of Medicine 353: 22092211.
Bender, C, Hall, H, Huang, J, Klimov, A, Cox, N, Hay, A, Gregory, V, Cameron, K, Lim, W and Subbarao, K (1999). Characterization of the surface proteins of influenza A (H5N1) viruses isolated from humans in 1997–1998. Virology 254: 115123.
Bibrack, B (1975). Serological studies on the involvement of influenza A2/Hongkong virus infection in kennel cough of dogs. Zentralblatt fuer Veterinaermedizin Reihe B 22: 2834.
Bibrack, B, Ackermann, U and Benary, F (1975). Serologic studies on the occurrence of virus infections in healthy dogs and in dogs with kennel cough. Zentralblatt fuer Veterinaermedizin Reihe B 22: 265273.
Bikour, MH, Frost, EH, Deslandes, S, Talbot, B, Weber, JM and Elazhary, Y (1995). Recent H3N2 swine influenza virus with haemagglutinin and nucleoprotein genes similar to 1975 human strains. Journal of General Virology 76: 697703.
Blok, J and Air, GM (1982). Variation in the membrane-insertion and ‘stalk’ sequences in eight subtypes of influenza type A virus neuraminidase. Biochemistry 21: 40014007.
Bridges, CB, Fukuda, K, Uyeki, TM, Cox, NJ, Singleton, JA and Centers for Disease Control and Prevention ACoIP (2002a). Prevention and control of influenza. Recommendations of the Advisory Committee on Immunization Practices (ACIP). Morbidity and Mortality Weekly Report. Recommendations and Reports 51: 131.
Bridges, CB, Lim, W, Hu-Primmer, J, Sims, L, Fukuda, K, Mak, KH, Rowe, T, Thompson, WW, Conn, L, Lu, X, Cox, NJ and Katz, JM (2002b). Risk of influenza A (H5N1) infection among poultry workers, Hong Kong, 1997–1998. Journal of Infectious Diseases 185: 10051010.
Bridges, CB, Kuehnert, MJ and Hall, CB (2003). Transmission of influenza: implications for control in health care settings. Clinical Infectious Diseases 37: 10941101.
Brown, EG (2000a). Influenza virus genetics. Biomedicine and Pharmacotherapy 54: 196209.
Brown, IH (2000b). The epidemiology and evolution of influenza viruses in pigs. Veterinary Microbiology 74: 2946.
Brown, IH, Harris, PA and Alexander, DJ (1995). Serological studies of influenza viruses in pigs in Great Britain 1991–2. Epidemiology and Infection 114: 511520.
Brown, IH, Ludwig, S, Olsen, CW, Hannoun, C, Scholtissek, C, Hinshaw, VS, Harris, PA, McCauley, JW, Strong, I and Alexander, DJ (1997). Antigenic and genetic analyses of H1N1 influenza A viruses from European pigs. Journal of General Virology 78: 553562.
Brown, IH, Harris, PA, McCauley, JW and Alexander, DJ (1998). Multiple genetic reassortment of avian and human influenza A viruses in European pigs, resulting in the emergence of an H1N2 virus of novel genotype. Journal of General Virology 79: 29472955.
Bucher, D and Palese, P (1975). The Biologically Active Proteins of Influenza Virus: Neuraminidase. New York: Academic Press.
Buonagurio, DA, Nakada, S, Parvin, JD, Krystal, M, Palese, P and Fitch, WM (1986). Evolution of human influenza A viruses over 50 years: rapid, uniform rate of change in NS gene. Science 232: 980982.
Butler, D (2006). Thai dogs carry bird-flu virus, but will they spread it? Nature 439: 773.
Callan, RJ, Early, G, Kida, H and Hinshaw, VS (1995). The appearance of H3 influenza viruses in seals. Journal of General Virology 76: 199203.
Campbell, CH, Webster, RG and Breese, SS Jr (1970). Fowl plague virus from man. Journal of Infectious Diseases 122: 513516.
Campitelli, L, Donatelli, I, Foni, E, Castrucci, MR, Fabiani, C, Kawaoka, Y, Krauss, S and Webster, RG (1997). Continued evolution of H1N1 and H3N2 influenza viruses in pigs in Italy. Virology 232: 310318.
Campitelli, L, Mogavero, E, De Marco, MA, Delogu, M, Puzelli, S, Frezza, F, Facchini, M, Chiapponi, C, Foni, E, Cordioli, P, Webby, R, Barigazzi, G, Webster, RG and Donatelli, I (2004). Interspecies transmission of an H7N3 influenza virus from wild birds to intensively reared domestic poultry in Italy. Virology 323: 2436.
Capua, I and Alexander, DJ (2004). Human health implications of avian influenza viruses and paramyxoviruses. European Journal of Clinical Microbiology and Infectious Diseases 23: 16.
Capua, I, Marangon, S, Cordioli, P, Bonfanti, L and Santucci, U (2002). H7N3 avian influenza in Italy. Veterinary Record 151: 743744.
Castrucci, MR and Kawaoka, Y (1993). Biologic importance of neuraminidase stalk length in influenza A virus. Journal of Virology 67: 759764.
Castrucci, MR, Donatelli, I, Sidoli, L, Barigazzi, G, Kawaoka, Y and Webster, RG (1993). Genetic reassortment between avian and human influenza A viruses in Italian pigs. Virology 193: 503506.
Chambers, TM, Yamnikova, S, Kawaoka, Y, Lvov, DK and Webster, RG (1989). Antigenic and molecular characterization of subtype H13 hemagglutinin of influenza virus. Virology 172: 180188.
Chang, CP, New, AE, Taylor, JF and Chiang, HS (1976). Influenza virus isolations from dogs during a human epidemic in Taiwan. International Journal of Zoonoses 3: 6164.
Choi, YK, Goyal, SM, Farnham, MW and Joo, HS (2002). Phylogenetic analysis of H1N2 isolates of influenza A virus from pigs in the United States. Virus Research 87: 173179.
Choi, YK, Nguyen, TD, Ozaki, H, Webby, RJ, Puthavathana, P, Buranathal, C, Chaisingh, A, Auewarakul, P, Hanh, NT, Ma, SK, Hui, PY, Guan, Y, Peiris, JS and Webster, RG (2005). Studies of H5N1 influenza virus infection of pigs by using viruses isolated in Vietnam and Thailand in 2004. Journal of Virology 79: 1082110825.
Claas, EC, Kawaoka, Y, de Jong, JC, Masurel, N and Webster, RG (1994). Infection of children with avian-human reassortant influenza virus from pigs in Europe. Virology 204: 453457.
Claas, EC, de Jong, JC, van Beek, R, Rimmelzwaan, GF and Osterhaus, AD (1998a). Human influenza virus A/HongKong/156/97 (H5N1) infection. Vaccine 16: 977978.
Claas, EC, Osterhaus, AD, van Beek, R, De Jong, JC, Rimmelzwaan, GF, Senne, DA, Krauss, S, Shortridge, KF and Webster, RG (1998b). Human influenza A H5N1 virus related to a highly pathogenic avian influenza virus. Lancet 351: 472477.
Clements, ML, Subbarao, EK, Fries, LF, Karron, RA, London, WT and Murphy, BR (1992). Use of single-gene reassortant viruses to study the role of avian influenza A virus genes in attenuation of wild-type human influenza A virus for squirrel monkeys and adult human volunteers. Journal of Clinical Microbiology 30: 655662.
Cleverley, DZ, Geller, HM and Lenard, J (1997). Characterization of cholesterol-free insect cells infectible by baculoviruses: effects of cholesterol on VSV fusion and infectivity and on cytotoxicity induced by influenza M2 protein. Experimental Cell Research 233: 288296.
Colman, PM, Laver, WG, Varghese, JN, Baker, AT, Tulloch, PA, Air, GM and Webster, RG (1987). Three-dimensional structure of a complex of antibody with influenza virus neuraminidase. Nature 326: 358363.
Couceiro, JN, Paulson, JC and Baum, LG (1993). Influenza virus strains selectively recognize sialyloligosaccharides on human respiratory epithelium; the role of the host cell in selection of hemagglutinin receptor specificity. Virus Research 29: 155165.
Couch, RB, Douglas, RG, Giggs, S, Knight, V and Kasel, JA (1969). Production of the influenza syndrome in man with equine influenza. Nature 224: 512514.
Cox, NJ and Subbarao, K (2000). Global epidemiology of influenza: past and present. Annual Review of Medicine 51: 407421.
Crawford, PC, Dubovi, EJ, Castleman, WL, Stephenson, I, Gibbs, EPJ, Chen, L, Smith, C, Hill, RC, Ferro, P, Pompey, J, Bright, RA, Medina, M-J, Group, IG, Johnson, CM, Olsen, CW, Cox, NJ, Klimov, AI, Katz, JM and Donis, RO (2005). Transmission of equine influenza virus to dogs. Science 310: 482485.
Crecelius, DM, Deom, CM and Schulze, IT (1984). Biological properties of a hemagglutinin mutant of influenza virus selected by host cells. Virology 139: 164177.
Crosby, A (1989). America's Forgotten Pandemic. Cambridge: Cambridge University Press, pp. 1351.
Dacso, CC, Couch, RB, Six, HR, Young, JF, Quarles, JM and Kasel, JA (1984). Sporadic occurrence of zoonotic swine influenza virus infections. Journal of Clinical Microbiology 20: 833835.
Dalton, RM, Mullin, AE, Amorim, MJ, Medcalf, E, Tiley, LS and Digard, P (2006). Temperature sensitive influenza A virus genome replication results from low thermal stability of polymerase–cRNA complexes. Virology Journal 3: 58.
de Jong, JC, Claas, EC, Osterhaus, AD, Webster, RG and Lim, WL (1997). A pandemic warning? Nature 389: 554.
Deom, CM, Caton, AJ and Schulze, IT (1986). Host cell-mediated selection of a mutant influenza A virus that has lost a complex oligosaccharide from the tip of the hemagglutinin. Proceedings of the National Academy of Sciences of the United States of America 83: 37713775.
Donatelli, I, Campitelli, L, Castrucci, MR, Ruggieri, A, Sidoli, L and Oxford, JS (1991). Detection of two antigenic subpopulations of A(H1N1) influenza viruses from pigs: antigenic drift or interspecies transmission? Journal of Medical Virology 34: 248257.
Easterday, BC (1980). Animals in the influenza world. Philosophical Transactions of the Royal Society of London – Series B: Biological Sciences 288: 433437.
Eigen, M and Schuster, P (1977). The hypercycle. A principle of natural self-organization. Part A: emergence of the hypercycle. Naturwissenschaften 64: 541565.
Fang, R, Min, Jou W, Huylebroeck, D, Devos, R and Fiers, W (1981). Complete structure of A/duck/Ukraine/63 influenza hemagglutinin gene: animal virus as progenitor of human H3 Hong Kong 1968 influenza hemagglutinin. Cell 25: 315323.
Ferguson, N (2006). Poverty, death, and a future influenza pandemic. Lancet 368: 21872188.
Ferguson, NM, Galvani, AP and Bush, RM (2003). Ecological and immunological determinants of influenza evolution. Nature 422: 428433.
Fitch, WM, Bush, RM, Bender, CA and Cox, NJ (1997). Long term trends in the evolution of H(3) HA1 human influenza type A. Proceedings of the National Academy of Sciences of the United States of America 94: 77127718.
Fouchier, RA, Schneeberger, PM, Rozendaal, FW, Broekman, JM, Kemink, SA, Munster, V, Kuiken, T, Rimmelzwaan, GF, Schutten, M, Van Doornum, GJ, Koch, G, Bosman, A, Koopmans, M and Osterhaus, AD (2004). Avian influenza A virus (H7N7) associated with human conjunctivitis and a fatal case of acute respiratory distress syndrome. Proceedings of the National Academy of Sciences of the United States of America 101: 13561361.
Gambaryan, AS, Tuzikov, AB, Piskarev, VE, Yamnikova, SS, Lvov, DK, Robertson, JS, Bovin, NV and Matrosovich, MN (1997). Specification of receptor-binding phenotypes of influenza virus isolates from different hosts using synthetic sialylglycopolymers: non-egg-adapted human H1 and H3 influenza A and influenza B viruses share a common high binding affinity for 6′-sialyl(N-acetyllactosamine). Virology 232: 345350.
Gambaryan, AS, Marinina, VP, Tuzikov, AB, Bovin, NV, Rudneva, IA, Sinitsyn, BV, Shilov, AA and Matrosovich, MN (1998). Effects of host-dependent glycosylation of hemagglutinin on receptor-binding properties on H1N1 human influenza A virus grown in MDCK cells and in embryonated eggs. Virology 247: 170177.
Gambaryan, A, Webster, R and Matrosovich, M (2002). Differences between influenza virus receptors on target cells of duck and chicken. Archives of Virology 147: 11971208.
Gammelin, M, Altmuller, A, Reinhardt, U, Mandler, J, Harley, VR, Hudson, PJ, Fitch, WM and Scholtissek, C (1990). Phylogenetic analysis of nucleoproteins suggests that human influenza A viruses emerged from a 19th-century avian ancestor. Molecular Biology and Evolution 7: 194200.
Gaydos, JC, Top, FH Jr, Hodder, RA and Russell, PK (2006). Swine influenza a outbreak, Fort Dix, New Jersey, 1976. Emerging Infectious Diseases 12: 2328.
Geraci, JR, St Aubin, DJ, Barker, IK, Webster, RG, Hinshaw, VS, Bean, WJ, Ruhnke, HL, Prescott, JH, Early, G, Baker, AS, Madoff, S and Schooley, RT (1982). Mass mortality of harbor seals: pneumonia associated with influenza A virus. Science 215: 11291131.
Gething, MJ, Bye, J, Skehel, J and Waterfield, M (1980). Cloning and DNA sequence of double-stranded copies of haemagglutinin genes from H2 and H3 strains elucidates antigenic shift and drift in human influenza virus. Nature 287: 301306.
Ghedin, E, Sengamalay, NA, Shumway, M, Zaborsky, J, Feldblyum, T, Subbu, V, Spiro, DJ, Sitz, J, Koo, H, Bolotov, P, Dernovoy, D, Tatusova, T, Bao, Y, St George, K, Taylor, J, Lipman, DJ, Fraser, CM, Taubenberger, JK and Salzberg, SL (2005). Large-scale sequencing of human influenza reveals the dynamic nature of viral genome evolution. Nature 437: 11621166.
Giannecchini, S, Campitelli, L, Calzoletti, L, De Marco, MA, Azzi, A and Donatelli, I (2006). Comparison of in vitro replication features of H7N3 influenza viruses from wild ducks and turkeys: potential implications for interspecies transmission. Journal of General Virology 87: 171175.
Gilsdorf, A, Boxall, N, Gasimov, V, Agayev, I, Mammadzade, F, Ursu, P, Gasimov, E, Brown, C, Mardel, S, Jankovic, D, Pimentel, G, Ayoub, IA, Elassal, EM, Salvi, C, Legros, D, Pessoa da, Silva C, Hay, A, Andraghetti, R, Rodier, G and Ganter, B (2006). Two clusters of human infection with influenza A/H5N1 virus in the Republic of Azerbaijan, February–March 2006. Euro Surveillance: Bulletin Europeen sur les Maladies Transmissibles=European Communicable Disease Bulletin 11: 122126.
Gitelman, AK, Kaverin, NV, Kharitonenkov, IG, Rudneva, IA, Sklyanskaya, EL and Zhdanov, VM (1986). Dissociation of the haemagglutination inhibition and the infectivity neutralization in the reactions of influenza A/USSR/90/77 (H1N1) virus variants with monoclonal antibodies. Journal of General Virology 67: 22472251.
Gorman, OT, Bean, WJ, Kawaoka, Y, Donatelli, I, Guo, YJ and Webster, RG (1991). Evolution of influenza A virus nucleoprotein genes: implications for the origins of H1N1 human and classical swine viruses. Journal of Virology 65: 37043714.
Gorman, OT, Bean, WJ and Webster, RG (1992). Evolutionary processes in influenza viruses: divergence, rapid evolution, and stasis. Current Topics in Microbiology and Immunology 176: 7597.
Gottschalk, A (1957). Neuraminidase: the specific enzyme of influenza virus and Vibrio cholerae. Biochimica et Biophysica Acta 23: 645646.
Gregory, V, Lim, W, Cameron, K, Bennett, M, Marozin, S, Klimov, A, Hall, H, Cox, N, Hay, A and Lin, YP (2001). Infection of a child in Hong Kong by an influenza A H3N2 virus closely related to viruses circulating in European pigs. Journal of General Virology 82: 13971406.
Gregory, V, Bennett, M, Orkhan, MH, Al Hajjar, S, Varsano, N, Mendelson, E, Zambon, M, Ellis, J, Hay, A and Lin, YP (2002). Emergence of influenza A H1N2 reassortant viruses in the human population during 2001. Virology 300: 17.
Gregory, V, Bennett, M, Thomas, Y, Kaiser, L, Wunderli, W, Matter, H, Hay, A and Lin, YP (2003). Human infection by a swine influenza A (H1N1) virus in Switzerland. Archives of Virology 148: 793802.
Guan, Y, Shortridge, KF, Krauss, S, Li, PH, Kawaoka, Y and Webster, RG (1996). Emergence of avian H1N1 influenza viruses in pigs in China. Journal of Virology 70: 80418046.
Guan, Y, Peiris, JS, Poon, LL, Dyrting, KC, Ellis, TM, Sims, L, Webster, RG and Shortridge, KF (2003). Reassortants of H5N1 influenza viruses recently isolated from aquatic poultry in Hong Kong SAR. Avian Diseases 47: 911913.
Gubareva, LV, Bethell, R, Hart, GJ, Murti, KG, Penn, CR and Webster, RG (1996). Characterization of mutants of influenza A virus selected with the neuraminidase inhibitor 4-guanidino-Neu5Ac2en. Journal of Virology 70: 18181827.
Gubareva, LV, Nedyalkova, MS, Novikov, DV, Murti, KG, Hoffmann, E and Hayden, FG (2002). A release-competent influenza A virus mutant lacking the coding capacity for the neuraminidase active site. Journal of General Virology 83: 26832692.
Gunther, I, Glatthaar, B, Doller, G and Garten, W (1993). A H1 hemagglutinin of a human influenza A virus with a carbohydrate-modulated receptor binding site and an unusual cleavage site. Virus Research 27: 147160.
Guo, Y, Wang, M, Kawaoka, Y, Gorman, O, Ito, T, Saito, T and Webster, RG (1992). Characterization of a new avian-like influenza A virus from horses in China. Virology 188: 245255.
Guthrie, AJ, Stevens, KB and Bosman, PP (1999). The circumstances surrounding the outbreak and spread of equine influenza in South Africa. Revue Scientifique et Technique 18: 179185.
Halvorson, D, Karunakaran, D, Senne, D, Kelleher, C, Bailey, C, Abraham, A, Hinshaw, V and Newman, J (1983). Epizootiology of avian influenza – simultaneous monitoring of sentinel ducks and turkeys in Minnesota. Avian Diseases 27: 7785.
Hannant, D and Mumford, JA (1996). Equine Influenza. St. Louis, MO: Elsevier Science Publishing Company.
Hartshorn, KL, White, MR, Voelker, DR, Coburn, J, Zaner, K and Crouch, EC (2000). Mechanism of binding of surfactant protein D to influenza A viruses: importance of binding to haemagglutinin to antiviral activity. Biochemical Journal 351: 449458.
Hatta, M and Kawaoka, Y (2002). The continued pandemic threat posed by avian influenza viruses in Hong Kong. Trends in Microbiology 10: 340344.
Hatta, M, Gao, P, Halfmann, P and Kawaoka, Y (2001). Molecular basis for high virulence of Hong Kong H5N1 influenza A viruses. Science 293: 18401842.
Hatta, M, Halfmann, P, Wells, K and Kawaoka, Y (2002). Human influenza a viral genes responsible for the restriction of its replication in duck intestine. Virology 295: 250255.
Hawgood, S, Brown, C, Edmondson, J, Stumbaugh, A, Allen, L, Goerke, J, Clark, H and Poulain, F (2004). Pulmonary collectins modulate strain-specific influenza a virus infection and host responses. Journal of Virology 78: 85658572.
Hay, AJ (1992). The action of adamantanamines against influenza A viruses: inhibition of the M2 ion channel protein. Seminars in Virology 3: 21.
Heilman, C and La Montagne, JR (1990). Influenza: status and prospects for its prevention, therapy, and control. Pediatric Clinics of North America 37: 669688.
Hinshaw, VS, Bean, WJ Jr, Webster, RG and Easterday, BC (1978). The prevalence of influenza viruses in swine and the antigenic and genetic relatedness of influenza viruses from man and swine. Virology 84: 5162.
Hinshaw, VS, Webster, RG, Naeve, CW and Murphy, BR (1983). Altered tissue tropism of human–avian reassortant influenza viruses. Virology 128: 260263.
Hinshaw, VS, Bean, WJ, Webster, RG, Rehg, JE, Fiorelli, P, Early, G, Geraci, JR and St Aubin, DJ (1984). Are seals frequently infected with avian influenza viruses? Journal of Virology 51: 863865.
Hinshaw, VS, Bean, WJ, Geraci, J, Fiorelli, P, Early, G and Webster, RG (1986). Characterization of two influenza A viruses from a pilot whale. Journal of Virology 58: 655656.
Hiromoto, Y, Yamazaki, Y, Fukushima, T, Saito, T, Lindstrom, SE, Omoe, K, Nerome, R, Lim, W, Sugita, S and Nerome, K (2000). Evolutionary characterization of the six internal genes of H5N1 human influenza A virus. Journal of General Virology 81: 12931303.
Holsinger, LJ, Nichani, D, Pinto, LH and Lamb, RA (1994). Influenza A virus M2 ion channel protein: a structure–function analysis. Journal of Virology 68: 15511563.
Honda, A and Ishihama, A (1997). The molecular anatomy of influenza virus RNA polymerase. Biological Chemistry 378: 483488.
Horimoto, T and Kawaoka, Y (2001). Pandemic threat posed by avian influenza A viruses. Clinical Microbiology Reviews 14: 129149.
Houser, RE and Heuschele, WP (1980). Evidence of prior infection with influenza A/Texas/77 (H3N2) virus in dogs with clinical parainfluenza. Canadian Journal of Comparative Medicine 44: 396402.
Hughes, MT, Matrosovich, M, Rodgers, ME, McGregor, M and Kawaoka, Y (2000). Influenza A viruses lacking sialidase activity can undergo multiple cycles of replication in cell culture, eggs, or mice. Journal of Virology 74: 52065212.
Hughes, MT, McGregor, M, Suzuki, T, Suzuki, Y and Kawaoka, Y (2001). Adaptation of influenza A viruses to cells expressing low levels of sialic acid leads to loss of neuraminidase activity. Journal of Virology 75: 37663770.
Inkster, MD, Hinshaw, VS and Schulze, IT (1993). The hemagglutinins of duck and human H1 influenza viruses differ in sequence conservation and in glycosylation. Journal of Virology 67: 74367443.
Isoda, N, Sakoda, Y, Kishida, N, Bai, GR, Matsuda, K, Umemura, T and Kida, H (2006). Pathogenicity of a highly pathogenic avian influenza virus, A/chicken/Yamaguchi/7/04 (H5N1) in different species of birds and mammals. Archives of Virology 151: 12671279.
Ito, T (2000). Interspecies transmission and receptor recognition of influenza A viruses. Microbiology and Immunology 44: 423430.
Ito, T and Kawaoka, Y (2000). Host-range barrier of influenza A viruses. Veterinary Microbiology 74: 7175.
Ito, T, Couceiro, JN, Kelm, S, Baum, LG, Krauss, S, Castrucci, MR, Donatelli, I, Kida, H, Paulson, JC, Webster, RG and Kawaoka, Y (1998). Molecular basis for the generation in pigs of influenza A viruses with pandemic potential. Journal of Virology 72: 73677373.
Ito, T, Kawaoka, Y, Nomura, A and Otsuki, K (1999). Receptor specificity of influenza A viruses from sea mammals correlates with lung sialyloligosaccharides in these animals. Journal of Veterinary Medical Science 61: 955958.
Janke, BH (1998). Classic swine influenza. Large Animal Practitioner 19: 2429.
Jones, YL and Swayne, DE (2004). Comparative pathobiology of low and high pathogenicity H7N3 Chilean avian influenza viruses in chickens. Avian Diseases 48: 119128.
Kandun, IN, Wibisono, H, Sedyaningsih, ER, Yusharmen, Hadisoedarsuno W, Purba, W, Santoso, H, Septiawati, C, Tresnaningsih, E, Heriyanto, B, Yuwono, D, Harun, S, Soeroso, S, Giriputra, S, Blair, PJ, Jeremijenko, A, Kosasih, H, Putnam, SD, Samaan, G, Silitonga, M, Chan, KH, Poon, LL, Lim, W, Klimov, A, Lindstrom, S, Guan, Y, Donis, R, Katz, J, Cox, N, Peiris, M and Uyeki, TM (2006). Three Indonesian clusters of H5N1 virus infection in 2005. New England Journal of Medicine 355: 21862194.
Karasin, AI, Brown, IH, Carman, S and Olsen, CW (2000a). Isolation and characterization of H4N6 avian influenza viruses from pigs with pneumonia in Canada. Journal of Virology 74: 93229327.
Karasin, AI, Olsen, CW and Anderson, GA (2000b). Genetic characterization of an H1N2 influenza virus isolated from a pig in Indiana. Journal of Clinical Microbiology 38: 24532456.
Karasin, AI, Schutten, MM, Cooper, LA, Smith, CB, Subbarao, K, Anderson, GA, Carman, S and Olsen, CW (2000c). Genetic characterization of H3N2 influenza viruses isolated from pigs in North America, 1977–1999: evidence for wholly human and reassortant virus genotypes. Virus Research 68: 7185.
Karasin, AI, Landgraf, J, Swenson, S, Erickson, G, Goyal, S, Woodruff, M, Scherba, G, Anderson, G and Olsen, CW (2002). Genetic characterization of H1N2 influenza A viruses isolated from pigs throughout the United States. Journal of Clinical Microbiology 40: 10731079.
Karasin, AI, West, K, Carman, S and Olsen, CW (2004). Characterization of avian H3N3 and H1N1 influenza A viruses isolated from pigs in Canada. Journal of Clinical Microbiology 42: 43494354.
Karasin, AI, Carman, S and Olsen, CW (2006). Identification of human H1N2 and human-swine reassortant H1N2 and H1N1 influenza A viruses among pigs in Ontario, Canada (2003 to 2005). Journal of Clinical Microbiology 44: 11231126.
Kasel, JA and Couch, RB (1969). Experimental infection in man and horses with influenza A viruses. Bulletin of the World Health Organization 41: 447452.
Katz, JM (2003). The impact of avian influenza viruses on public health. Avian Diseases 47: 914920.
Kaverin, NV and Klenk, HD (1999). Strain-specific differences in the effect of influenza A virus neuraminidase on vector-expressed hemagglutinin. Archives of Virology 144: 781786.
Kaverin, NV, Gambaryan, AS, Bovin, NV, Rudneva, IA, Shilov, AA, Khodova, OM, Varich, NL, Sinitsin, BV, Makarova, NV and Kropotkina, EA (1998). Postreassortment changes in influenza A virus hemagglutinin restoring HA–NA functional match. Virology 244: 315321.
Kaverin, NV, Matrosovich, MN, Gambaryan, AS, Rudneva, IA, Shilov, AA, Varich, NL, Makarova, NV, Kropotkina, EA and Sinitsin, BV (2000). Intergenic HA–NA interactions in influenza A virus: postreassortment substitutions of charged amino acid in the hemagglutinin of different subtypes. Virus Research 66: 123129.
Kawaoka, Y, Krauss, S and Webster, RG (1989). Avian-to-human transmission of the PB1 gene of influenza A viruses in the 1957 and 1968 pandemics. Journal of Virology 63: 46034608.
Kenny, C (2006). Are we ready for a flu pandemic? Nursing Times 102: 89.
Kida, H, Shortridge, KF and Webster, RG (1988). Origin of the hemagglutinin gene of H3N2 influenza viruses from pigs in China. Virology 162: 160166.
Kida, H, Ito, T, Yasuda, J, Shimizu, Y, Itakura, C, Shortridge, KF, Kawaoka, Y and Webster, RG (1994). Potential for transmission of avian influenza viruses to pigs. Journal of General Virology 75: 21832188.
Kilpatrick, AM, Chmura, AA, Gibbons, DW, Fleischer, RC, Marra, PP and Daszak, P (2006). From the cover: predicting the global spread of H5N1 avian influenza. Proceedings of the National Academy of Sciences of the United States of America 103: 1936819373.
Kimura, K, Adlakha, A and Simon, PM (1998). Fatal case of swine influenza virus in an immunocompetent host. Mayo Clinic Proceedings 73: 243245.
Kistner, O, Muller, H, Becht, H and Scholtissek, C (1985). Phosphopeptide fingerprints of nucleoproteins of various influenza A virus strains grown in different host cells. Journal of General Virology 66: 465472.
Klimov, A, Simonsen, L, Fukuda, K and Cox, N (1999). Surveillance and impact of influenza in the United States. Vaccine 17: S4246.
Klingeborn, B, Englund, L, Rott, R, Juntti, N and Rockborn, G (1985). An avian influenza A virus killing a mammalian species – the mink. Brief report. Archives of Virology 86: 347351.
Kobasa, D, Kodihalli, S, Luo, M, Castrucci, MR, Donatelli, I, Suzuki, Y, Suzuki, T and Kawaoka, Y (1999). Amino acid residues contributing to the substrate specificity of the influenza A virus neuraminidase. Journal of Virology 73: 67436751.
Kobasa, D, Wells, K and Kawaoka, Y (2001). Amino acids responsible for the absolute sialidase activity of the influenza A virus neuraminidase: relationship to growth in the duck intestine. Journal of Virology 75: 1177311780.
Kobasa, D, Takada, A, Shinya, K, Hatta, M, Halfmann, P, Theriault, S, Suzuki, H, Nishimura, H, Mitamura, K, Sugaya, N, Usui, T, Murata, T, Maeda, Y, Watanabe, S, Suresh, M, Suzuki, T, Suzuki, Y, Feldmann, H and Kawaoka, Y (2004). Enhanced virulence of influenza A viruses with the haemagglutinin of the 1918 pandemic virus. Nature 431: 703707.
Koen, JS (1919). A practical method for field diagnosis of swine diseases. American Journal of Veterinary Medicine 14: 468470.
Kothalawala, H, Toussaint, MJ and Gruys, E (2006). An overview of swine influenza. Veterinary Quarterly 28: 4653.
Kuiken, T, Fouchier, RA, Schutten, M, Rimmelzwaan, GF, van Amerongen, G, van Riel, D, Laman, JD, de Jong, T, van Doornum, G, Lim, W, Ling, AE, Chan, PK, Tam, JS, Zambon, MC, Gopal, R, Drosten, C, van der Werf, S, Escriou, N, Manuguerra, JC, Stohr, K, Peiris, JS and Osterhaus, AD (2003). Newly discovered coronavirus as the primary cause of severe acute respiratory syndrome. Lancet 362: 263270.
Kuiken, T, Rimmelzwaan, G, van Riel, D, van Amerongen, G, Baars, M, Fouchier, R and Osterhaus, A (2004). Avian H5N1 influenza in cats. Science 306: 241.
Kuiken, T, Fouchier, R, Rimmelzwaan, G, Osterhaus, A and Roeder, P (2006). Feline friend or potential foe? Nature 440: 741742.
Kundin, WD (1970). Hong Kong A-2 influenza virus infection among swine during a human epidemic in Taiwan. Nature 228: 857.
Lamb, R and Krug, R (2006). Orthomyxoviruses: The Viruses and their Replication. Philadelphia, PA: Lippincott Williams and Wilkins.
Landolt, GA, Karasin, AI, Phillips, L and Olsen, CW (2003). Comparison of the pathogenesis of two genetically different H3N2 influenza A viruses in pigs. Journal of Clinical Microbiology 41: 19361941.
Landolt, GA, Karasin, AI, Schutten, MM and Olsen, CW (2006). Restricted infectivity of a human-lineage H3N2 influenza A virus in pigs is hemagglutinin and neuraminidase gene dependent. Journal of Clinical Microbiology 44: 297301.
Laver, WG, Bischofberger, N and Webster, RG (2000). The origin and control of pandemic influenza. Perspectives in Biology and Medicine 43: 173192.
Layne, SP (2006). Human influenza surveillance: the demand to expand. Emerging Infectious Diseases 12: 562568.
Lee, MT, Klumpp, K, Digard, P and Tiley, L (2003). Activation of influenza virus RNA polymerase by the 5′ and 3′ terminal duplex of genomic RNA. Nucleic Acids Research 31: 16241632.
Lekcharoensuk, P, Lager, KM, Vemulapalli, R, Woodruff, M, Vincent, AL and Richt, JA (2006). Novel swine influenza virus subtype H3N1, United States. Emerging Infectious Diseases 12: 787794.
Leschnik, M, Weikel, J, Moestl, K, Revilla-Fernandez, S, Wodak, E, Bago, Z, Vanek, E, Benetka, V, Hess, M and Thalhammer, JG (2007). Subclinical infection with avian influenza A (H5N1) virus in cats. Emerging Infectious Diseases 13: 243247.
Levy, JA, Hoffman, AD, Kramer, SM, Landis, JA, Shimabukuro, JM and Oshiro, LS (1984). Isolation of lymphocytopathic retroviruses from San Francisco patients with AIDS. Science 225: 840842.
Li, KS, Guan, Y, Wang, J, Smith, GJ, Xu, KM, Duan, L, Rahardjo, AP, Puthavathana, P, Buranathai, C, Nguyen, TD, Estoepangestie, AT, Chaisingh, A, Auewarakul, P, Long, HT, Hanh, NT, Webby, RJ, Poon, LL, Chen, H, Shortridge, KF, Yuen, KY, Webster, RG and Peiris, JS (2004). Genesis of a highly pathogenic and potentially pandemic H5N1 influenza virus in eastern Asia. Nature 430: 209213.
Li, Z, Chen, H, Jiao, P, Deng, G, Tian, G, Li, Y, Hoffmann, E, Webster, RG, Matsuoka, Y and Yu, K (2005). Molecular basis of replication of duck H5N1 influenza viruses in a mammalian mouse model. Journal of Virology 79: 1205812064.
Lin, YP, Shaw, M, Gregory, V, Cameron, K, Lim, W, Klimov, A, Subbarao, K, Guan, Y, Krauss, S, Shortridge, K, Webster, R, Cox, N and Hay, A (2000). Avian-to-human transmission of H9N2 subtype influenza A viruses: relationship between H9N2 and H5N1 human isolates. Proceedings of the National Academy of Sciences of the United States of America 97: 96549658.
Lipatov, AS, Govorkova, EA, Webby, RJ, Ozaki, H, Peiris, M, Guan, Y, Poon, L and Webster, RG (2004). Influenza: emergence and control. Journal of Virology 78: 89518959.
Liu, M, Guan, Y, Peiris, M, He, S, Webby, RJ, Perez, D and Webster, RG (2003a). The quest of influenza A viruses for new hosts. Avian Diseases 47: 849856.
Liu, M, He, S, Walker, D, Zhou, N, Perez, DR, Mo, B, Li, F, Huang, X, Webster, RG and Webby, RJ (2003b). The influenza virus gene pool in a poultry market in South Central China. Virology 305: 267275.
Liu, T and Ye, Z (2002). Restriction of viral replication by mutation of the influenza virus matrix protein. Journal of Virology 76: 1305513061.
Luo, G, Chung, J and Palese, P (1993). Alterations of the stalk of the influenza virus neuraminidase: deletions and insertions. Virus Research 29: 141153.
Lvov, DK, Zdanov, VM, Sazonov, AA, Braude, NA, Vladimirtceva, EA, Agafonova, LV, Skljanskaja, EI, Kaverin, NV, Reznik, VI, Pysina, TV, Oserovic, AM, Berzin, AA, Mjasnikova, IA, Podcernjaeva, RY, Klimenko, SM, Andrejev, VP and Yakhno, MA (1978). Comparison of influenza viruses isolated from man and from whales. Bulletin of the World Health Organization 56: 923930.
Ma, W, Gramer, M, Rossow, K and Yoon, KJ (2006). Isolation and genetic characterization of new reassortant H3N1 swine influenza virus from pigs in the midwestern United States. Journal of Virology 80: 50925096.
Makarova, NV, Ozaki, H, Kida, H, Webster, RG and Perez, DR (2003). Replication and transmission of influenza viruses in Japanese quail. Virology 310: 815.
Maldin, B and Criss, K (2006). Risky business: planning for pandemic flu. Biosecurity and Bioterrorism 4: 307312.
Mancini, G, Donatelli, I, Rozera, C, Arangio, Ruiz G and Butto, S (1985). Antigenic and biochemical analysis of influenza ‘A’ H3N2 viruses isolated from pigs. Archives of Virology 83: 157167.
Manuguerra, JC, Hannoun, C, Simon, F, Villar, E and Cabezas, JA (1993). Natural infection of dogs by influenza C virus: a serological survey in Spain. New Microbiologica 16: 367371.
Mase, M, Tanimura, N, Imada, T, Okamatsu, M, Tsukamoto, K and Yamaguchi, S (2006). Recent H5N1 avian influenza A virus increases rapidly in virulence to mice after a single passage in mice. Journal of General Virology 87: 36553659.
Massin, P, van der Werf, S and Naffakh, N (2001). Residue 627 of PB2 is a determinant of cold sensitivity in RNA replication of avian influenza viruses. Journal of Virology 75: 53985404.
Matrosovich, M, Zhou, N, Kawaoka, Y and Webster, R (1999). The surface glycoproteins of H5 influenza viruses isolated from humans, chickens, and wild aquatic birds have distinguishable properties. Journal of Virology 73: 11461155.
Matrosovich, M, Tuzikov, A, Bovin, N, Gambaryan, A, Klimov, A, Castrucci, MR, Donatelli, I and Kawaoka, Y (2000). Early alterations of the receptor-binding properties of H1, H2, and H3 avian influenza virus hemagglutinins after their introduction into mammals. Journal of Virology 74: 85028512.
Matrosovich, MN, Gambaryan, AS, Teneberg, S, Piskarev, VE, Yamnikova, SS, Lvov, DK, Robertson, JS and Karlsson, KA (1997). Avian influenza A viruses differ from human viruses by recognition of sialyloligosaccharides and gangliosides and by a higher conservation of the HA receptor-binding site. Virology 233: 224234.
Matrosovich, MN, Krauss, S and Webster, RG (2001). H9N2 influenza A viruses from poultry in Asia have human virus-like receptor specificity. Virology 281: 156162.
Matrosovich, MN, Matrosovich, TY, Gray, T, Roberts, NA and Klenk, HD (2004a). Human and avian influenza viruses target different cell types in cultures of human airway epithelium. Proceedings of the National Academy of Sciences of the United States of America 101: 46204624.
Matrosovich, MN, Matrosovich, TY, Gray, T, Roberts, NA and Klenk, HD (2004b). Neuraminidase is important for the initiation of influenza virus infection in human airway epithelium. Journal of Virology 78: 1266512667.
McCauley, JW and Penn, CR (1990). The critical cut-off temperature of avian influenza viruses. Virus Research 17: 191198.
McKimm-Breschkin, JL, Blick, TJ, Sahasrabudhe, A, Tiong, T, Marshall, D, Hart, GJ, Bethell, RC and Penn, CR (1996). Generation and characterization of variants of NWS/G70C influenza virus after in vitro passage in 4-amino-Neu5Ac2en and 4-guanidino-Neu5Ac2en. Antimicrobial Agents and Chemotherapy 40: 4046.
McQueen, JL, Steele, JH and Robinson, RQ (1968). Influenza in animals. Advances in Veterinary Science 12: 285336.
Medeiros, R, Naffakh, N, Manuguerra, JC and van der Werf, S (2004). Binding of the hemagglutinin from human or equine influenza H3 viruses to the receptor is altered by substitutions at residue 193. Archives of Virology 149: 16631671.
Meltzer, MI, Cox, NJ and Fukuda, K (1999). The economic impact of pandemic influenza in the United States: priorities for intervention. Emerging Infectious Diseases 5: 659671.
Mitnaul, LJ, Matrosovich, MN, Castrucci, MR, Tuzikov, AB, Bovin, NV, Kobasa, D and Kawaoka, Y (2000). Balanced hemagglutinin and neuraminidase activities are critical for efficient replication of influenza A virus. Journal of Virology 74: 60156020.
Morse, SS (1997). The public health threat of emerging viral disease. Journal of Nutrition 127: 951S957S.
Murphy, BR, Hinshaw, VS, Sly, DL, London, WT, Hosier, NT, Wood, FT, Webster, RG and Chanock, RM (1982). Virulence of avian influenza A viruses for squirrel monkeys. Infection and Immunity 37: 11191126.
Murphy, BR, Buckler-White, AJ, London, WT and Snyder, MH (1989). Characterization of the M protein and nucleoprotein genes of an avian influenza A virus which are involved in host range restriction in monkeys. Vaccine 7: 557561.
Murray, K, Selleck, P, Hooper, P, Hyatt, A, Gleeson, LJ, Westbury, H, Hiley, L, Selvey, L, Rodwell, B and Ketterer, PJ (1995). A morbillivirus that caused fatal disease in horses and humans. Science 268: 9497.
Mutinelli, F, Capua, I, Terregino, C and Cattoli, G (2003). Clinical, gross, and microscopic findings in different avian species naturally infected during the H7N1 low- and high-pathogenicity avian influenza epidemics in Italy during 1999 and 2000. Avian Diseases 47: 844848.
Myers, KP, Olsen, CW, Setterquist, SF, Capuano, AW, Donham, KJ, Thacker, EL, Merchant, JA and Gray, GC (2006). Are swine workers in the United States at increased risk of infection with zoonotic influenza virus? Clinical Infectious Diseases 42: 1420.
Naeve, CW, Hinshaw, VS and Webster, RG (1984). Mutations in the hemagglutinin receptor-binding site can change the biological properties of an influenza virus. Journal of Virology 51: 567569.
Nakajima, K, Nakajima, S, Shortridge, KF and Kendal, AP (1982). Further genetic evidence for maintenance of early Hong Kong-like influenza A(H3N2) strains in swine until 1976. Virology 116: 562572.
Nerome, K, Kanegae, Y, Shortridge, KF, Sugita, S and Ishida, M (1995). Genetic analysis of porcine H3N2 viruses originating in southern China. Journal of General Virology 76: 613624.
Neumann, G and Kawaoka, Y (2006). Host range restriction and pathogenicity in the context of influenza pandemic. Emerging Infectious Diseases 12: 881886.
Nikitin, T, Cohen, D, Todd, JD and Lief, FS (1972). Epidemiological studies of A/Hong Kong/68 virus infection in dogs. Bulletin of the World Health Organization 47: 471479.
Noda, T, Sagara, H, Yen, A, Takada, A, Kida, H, Cheng, RH and Kawaoka, Y (2006). Architecture of ribonucleoprotein complexes in influenza A virus particles. Nature 439: 490492.
Ohwada, K, Kitame, F, Sugawara, K, Nishimura, H, Homma, M and Nakamura, K (1987). Distribution of the antibody to influenza C virus in dogs and pigs in Yamagata Prefecture, Japan. Microbiology and Immunology 31: 11731180.
Olsen, CW (2002). The emergence of novel swine influenza viruses in North America. Virus Research 85: 199210.
Olsen, CW, Brammer, L, Easterday, BC, Arden, N, Belay, E, Baker, I and Cox, NJ (2002). Serologic evidence of H1 swine influenza virus infection in swine farm residents and employees. Emerging Infectious Diseases 8: 814819.
Olsen, CW, Karasin, AI, Carman, S, Li, Y, Bastien, N, Ojkic, D, Alves, D, Charbonneau, G, Henning, BM, Low, DE, Burton, L and Broukhanski, G (2006). Triple reassortant H3N2 influenza A viruses, Canada, 2005. Emerging Infectious Diseases 12: 11321135.
Ottis, K, Sidoli, L, Bachmann, PA, Webster, RG and Kaplan, MM (1982). Human influenza A viruses in pigs: isolation of a H3N2 strain antigenically related to A/England/42/72 and evidence for continuous circulation of human viruses in the pig population. Archives of Virology 73: 103108.
Palese, P, Tobita, K, Ueda, M and Compans, RW (1974). Characterization of temperature sensitive influenza virus mutants defective in neuraminidase. Virology 61: 397410.
Paniker, CK and Nair, CM (1972). Experimental infection of animals with influenza virus types A and B. Bulletin of the World Health Organization 47: 461463.
Patriarca, PA, Kendal, AP, Zakowski, PC, Cox, NJ, Trautman, MS, Cherry, JD, Auerbach, DM, McCusker, J, Belliveau, RR and Kappus, KD (1984). Lack of significant person-to-person spread of swine influenza-like virus following fatal infection in an immunocompromised child. American Journal of Epidemiology 119: 152158.
Peek, SF, Landolt, G, Karasin, AI, Slack, J, Steinberg, H, Semrad, SD and Olsen, CW (2004). Acute respiratory distress syndrome and fatal interstitial pneumonia associated with equine influenza in a neonatal foal. Journal of Veterinary Internal Medicine 18: 132134.
Peiris, JS, Guan, Y, Markwell, D, Ghose, P, Webster, RG and Shortridge, KF (2001). Cocirculation of avian H9N2 and contemporary ‘human’ H3N2 influenza A viruses in pigs in southeastern China: potential for genetic reassortment? Journal of Virology 75: 96799686.
Penn, C (1989). The role of RNA segment 1 in an in vitro host restriction occurring in an avian influenza virus mutant. Virus Research 12: 349359.
Pensaert, M, Ottis, K, Vandeputte, J, Kaplan, MM and Bachmann, PA (1981). Evidence for the natural transmission of influenza A virus from wild ducts to swine and its potential importance for man. Bulletin of the World Health Organization 59: 7578.
Perez, DR, Webby, RJ, Hoffmann, E and Webster, RG (2003). Land-based birds as potential disseminators of avian mammalian reassortant influenza A viruses. Avian Diseases 47: 11141117.
Pinto, LH, Holsinger, LJ and Lamb, RA (1992). Influenza virus M2 protein has ion channel activity. Cell 69: 517528.
Potter, CW (2001). A history of influenza. Journal of Applied Microbiology 91: 572579.
Puthavathana, P, Auewarakul, P, Charoenying, PC, Sangsiriwut, K, Pooruk, P, Boonnak, K, Khanyok, R, Thawachsupa, P, Kijphati, R and Sawanpanyalert, P (2005). Molecular characterization of the complete genome of human influenza H5N1 virus isolates from Thailand. Journal of General Virology 86: 423433.
Puzelli, S, Di Trani, L, Fabiani, C, Campitelli, L, De Marco, MA, Capua, I, Aguilera, JF, Zambon, M and Donatelli, I (2005). Serological analysis of serum samples from humans exposed to avian H7 influenza viruses in Italy between 1999 and 2003. Journal of Infectious Diseases 192: 13181322.
Ramirez, G, Fehervari, T, Paasch, LH and Calderon, NL (2005). Haematological and histological findings in birds experimentally infected with highly pathogenic H5N2 avian influenza virus. Acta Veterinaria Hungarica 53: 493499.
Richardson, JC and Akkina, RK (1991). NS2 protein of influenza virus is found in purified virus and phosphorylated in infected cells. Archives of Virology 116: 6980.
Rimmelzwaan, GF, de Jong, JC, Bestebroer, TM, van Loon, AM, Claas, EC, Fouchier, RA and Osterhaus, AD (2001). Antigenic and genetic characterization of swine influenza A (H1N1) viruses isolated from pneumonia patients in The Netherlands. Virology 282: 301306.
Rimmelzwaan, GF, van Riel, D, Baars, M, Bestebroer, TM, van Amerongen, G, Fouchier, RA, Osterhaus, AD and Kuiken, T (2006). Influenza A virus (H5N1) infection in cats causes systemic disease with potential novel routes of virus spread within and between hosts. American Journal of Pathology 168: 176183; quiz 364.
Robertson, JS, Nicolson, C, Major, D, Robertson, EW and Wood, JM (1993). The role of amniotic passage in the egg-adaptation of human influenza virus is revealed by haemagglutinin sequence analyses. Journal of General Virology 74: 20472051.
Robertson, JS, Cook, P, Attwell, AM and Williams, SP (1995). Replicative advantage in tissue culture of egg-adapted influenza virus over tissue-culture derived virus: implications for vaccine manufacture. Vaccine 13: 15831588.
Rogers, GN and D'Souza, BL (1989). Receptor binding properties of human and animal H1 influenza virus isolates. Virology 173: 317322.
Rogers, GN and Paulson, JC (1983). Receptor determinants of human and animal influenza virus isolates: differences in receptor specificity of the H3 hemagglutinin based on species of origin. Virology 127: 361373.
Rogers, GN, Pritchett, TJ, Lane, JL and Paulson, JC (1983). Differential sensitivity of human, avian, and equine influenza A viruses to a glycoprotein inhibitor of infection: selection of receptor specific variants. Virology 131: 394408.
Rohm, C, Horimoto, T, Kawaoka, Y, Suss, J and Webster, RG (1995). Do hemagglutinin genes of highly pathogenic avian influenza viruses constitute unique phylogenetic lineages? Virology 209: 664670.
Romanova, J, Katinger, D, Ferko, B, Voglauer, R, Mochalova, L, Bovin, N, Lim, W, Katinger, H and Egorov, A (2003). Distinct host range of influenza H3N2 virus isolates in Vero and MDCK cells is determined by cell specific glycosylation pattern. Virology 307: 9097.
Rota, PA, Rocha, EP, Harmon, MW, Hinshaw, VS, Sheerar, MG, Kawaoka, Y, Cox, NJ and Smith, TF (1989). Laboratory characterization of a swine influenza virus isolated from a fatal case of human influenza. Journal of Clinical Microbiology 27: 14131416.
Rudneva, IA, Kovaleva, VP, Varich, NL, Farashyan, VR, Gubareva, LV, Yamnikova, SS, Popova, IA, Presnova, VP and Kaverin, NV (1993). Influenza A virus reassortants with surface glycoprotein genes of the avian parent viruses: effects of HA and NA gene combinations on virus aggregation. Archives of Virology 133: 437450.
Ryan-Poirier, KA and Kawaoka, Y (1991). Distinct glycoprotein inhibitors of influenza A virus in different animal sera. Journal of Virology 65: 389395.
Saito, T, Lim, W, Suzuki, T, Suzuki, Y, Kida, H, Nishimura, SI and Tashiro, M (2001). Characterization of a human H9N2 influenza virus isolated in Hong Kong. Vaccine 20: 125133.
Schnurrenberger, PR, Woods, GT and Martin, RJ (1970). Serologic evidence of human infection with swine influenza virus. American Review of Respiratory Disease 102: 356361.
Scholtissek, C (1990). Pigs as the ‘mixing vessel’ for the creation of new pandemic influenza A viruses. Medical Principles and Practice 2: 6571.
Scholtissek, C and Naylor, E (1988). Fish farming and influenza pandemics. Nature 331: 215.
Scholtissek, C, Koennecke, I and Rott, R (1978). Host range recombinants of fowl plague (influenza A) virus. Virology 91: 7985.
Scholtissek, C, Burger, H, Bachmann, PA and Hannoun, C (1983). Genetic relatedness of hemagglutinins of the H1 subtype of influenza A viruses isolated from swine and birds. Virology 129: 521523.
Scholtissek, C, Burger, H, Kistner, O and Shortridge, KF (1985). The nucleoprotein as a possible major factor in determining host specificity of influenza H3N2 viruses. Virology 147: 287294.
Scholtissek, C, Stech, J, Krauss, S and Webster, RG (2002). Cooperation between the hemagglutinin of avian viruses and the matrix protein of human influenza A viruses. Journal of Virology 76: 17811786.
Schultz, U, Fitch, WM, Ludwig, S, Mandler, J and Scholtissek, C (1991). Evolution of pig influenza viruses. Virology 183: 6173.
Shinya, K, Ebina, M, Yamada, S, Ono, M, Kasai, N and Kawaoka, Y (2006). Avian flu: influenza virus receptors in the human airway. Nature 440: 435436.
Shortridge, KF, Webster, RG, Butterfield, WK and Campbell, CH (1977). Persistence of Hong Kong influenza virus variants in pigs. Science 196: 14541455.
Shortridge, KF, Chan, WH and Guan, Y (1995). Epidemiology of the equine influenza outbreak in China, 1993–94. Veterinary Record 136: 160161.
Shu, LL, Lin, YP, Wright, SM, Shortridge, KF and Webster, RG (1994). Evidence for interspecies transmission and reassortment of influenza A viruses in pigs in southern China. Virology 202: 825833.
Skehel, JJ and Wiley, DC (2000). Receptor binding and membrane fusion in virus entry: the influenza hemagglutinin. Annual Review of Biochemistry 69: 531569.
Snyder, MH, Buckler-White, AJ, London, WT, Tierney, EL and Murphy, BR (1987). The avian influenza virus nucleoprotein gene and a specific constellation of avian and human virus polymerase genes each specify attenuation of avian-human influenza A/Pintail/79 reassortant viruses for monkeys. Journal of Virology 61: 28572863.
Snyder, MH, London, WT, Maassab, HF, Chanock, RM and Murphy, BR (1990). A 36 nucleotide deletion mutation in the coding region of the NS1 gene of an influenza A virus RNA segment 8 specifies a temperature-dependent host range phenotype. Virus Research 15: 6983.
Song, DS, Lee, JY, Oh, JS, Lyoo, KS, Yoon, KJ, Park, YH and Park, BK (2003). Isolation of H3N2 swine influenza virus in South Korea. Journal of Veterinary Diagnostic Investigation 15: 3034.
Songsermn, T, Amonsin, A, Jam-on, R, Sae-Heng, N, Meemak, N, Pariyothorn, N, Payungporn, S, Theamboonlers, A and Poovorawan, Y (2006a). Avian influenza H5N1 in naturally infected domestic cat. Emerging Infectious Diseases 12: 681683.
Songsermn, T, Amonsin, A, Jam-on, R, Sae-Heng, N, Pariyothorn, N, Payungporn, S, Theamboonlers, A, Chutinimitkul, S, Thanawongnuwech, R and Poovorawan, Y (2006b). Fatal avian influenza A H5N1 in a dog. Emerging Infectious Diseases 12: 17441747.
Sovinova, O, Tumova, B, Pouska, F and Nemec, J (1958). Isolation of a virus causing respiratory disease in horses. Acta Virologica 2: 5261.
Stevens, J, Corper, AL, Basler, CF, Taubenberger, JK, Palese, P and Wilson, IA (2004). Structure of the uncleaved human H1 hemagglutinin from the extinct 1918 influenza virus. Science 303: 18661870.
Suarez, DL, Perdue, ML, Cox, N, Rowe, T, Bender, C, Huang, J and Swayne, DE (1998). Comparisons of highly virulent H5N1 influenza A viruses isolated from humans and chickens from Hong Kong. Journal of Virology 72: 66786688.
Subbarao, EK, London, W and Murphy, BR (1993). A single amino acid in the PB2 gene of influenza A virus is a determinant of host range. Journal of Virology 67: 17611764.
Subbarao, EK, Swayne, DE and Olsen, CW (2006). Epidemiology and Control of Human and Animal Influenza. Norfolk, UK: Caister Academic Press, pp. 229280.
Suzuki, T, Horiike, G, Yamazaki, Y, Kawabe, K, Masuda, H, Miyamoto, D, Matsuda, M, Nishimura, SI, Yamagata, T, Ito, T, Kida, H, Kawaoka, Y and Suzuki, Y (1997). Swine influenza virus strains recognize sialylsugar chains containing the molecular species of sialic acid predominantly present in the swine tracheal epithelium. FEBS Letters 404: 192196.
Suzuki, Y (1994). Gangliosides as influenza virus receptors. Variation of influenza viruses and their recognition of the receptor sialo-sugar chains. Progress in Lipid Research 33: 429457.
Suzuki, Y, Ito, T, Suzuki, T, Holland, RE Jr, Chambers, TM, Kiso, M, Ishida, H and Kawaoka, Y (2000). Sialic acid species as a determinant of the host range of influenza A viruses. Journal of Virology 74: 1182511831.
Swayne, DE and Suarez, DL (2000). Highly pathogenic avian influenza. Revue Scientifique et Technique 19: 463482.
Taubenberger, JK (2003). Fixed and frozen flu: the 1918 influenza and lessons for the future. Avian Diseases 47: 789791.
Taubenberger, JK and Morens, DM (2006). 1918 Influenza: the mother of all pandemics. Emerging Infectious Diseases 12: 1522.
Taubenberger, JK, Reid, AH and Fanning, TG (2000). The 1918 influenza virus: a killer comes into view. Virology 274: 241245.
Taylor, HR and Turner, AJ (1977). A case report of fowl plague keratoconjunctivitis. British Journal of Ophthalmology 61: 8688.
Thacker, EL, Thacker, BJ and Janke, BH (2001). Interaction between Mycoplasma hyopneumoniae and swine influenza virus. Journal of Clinical Microbiology 39: 25252530.
Thompson, WW, Shay, DK, Weintraub, E, Brammer, L, Cox, N, Anderson, LJ and Fukuda, K (2003). Mortality associated with influenza and respiratory syncytial virus in the United States. JAMA 289: 179186.
Tian, SF, Buckler-White, AJ, London, WT, Reck, LJ, Chanock, RM and Murphy, BR (1985). Nucleoprotein and membrane protein genes are associated with restriction of replication of influenza A/Mallard/NY/78 virus and its reassortants in squirrel monkey respiratory tract. Journal of Virology 53: 771775.
Todd, JD and Cohen, D (1968). Studies of influenza in dogs. I. Susceptibility of dogs to natural and experimental infection with human A2 and B influenza virus. American Journal of Epidemiology 87: 426439.
Tumova, B (1980). Equine influenza – a segment in influenza virus ecology. Comparative Immunology, Microbiology and Infectious Diseases 3: 4559.
Tumpey, TM, Basler, CF, Aguilar, PV, Zeng, H, Solorzano, A, Swayne, DE, Cox, NJ, Katz, JM, Taubenberger, JK, Palese, P and Garcia-Sastre, A (2005). Characterization of the reconstructed 1918 Spanish influenza pandemic virus. Science 310: 7780.
Uppal, PK, Yadav, MP and Oberoi, MS (1989). Isolation of A/Equi-2 virus during 1987 equine influenza epidemic in India. Equine Veterinary Journal 21: 364366.
Uyeki, TM, Chong, YH, Katz, JM, Lim, W, Ho, YY, Wang, SS, Tsang, TH, Au, WW, Chan, SC, Rowe, T, Hu-Primmer, J, Bell, JC, Thompson, WW, Bridges, CB, Cox, NJ, Mak, KH and Fukuda, K (2002). Lack of evidence for human-to-human transmission of avian influenza A (H9N2) viruses in Hong Kong, China 1999. Emerging Infectious Diseases 8: 154159.
van Eijk, M, van de Lest, CH, Batenburg, JJ, Vaandrager, AB, Meschi, J, Hartshorn, KL, van Golde, LM and Haagsman, HP (2002). Porcine surfactant protein D is N-glycosylated in its carbohydrate recognition domain and is assembled into differently charged oligomers. American Journal of Respiratory Cell and Molecular Biology 26: 739747.
van Gils, JA, Munster, VJ, Radersma, R, Liefhebber, D, Fouchier, R and Klaassen, M (2007). Hampered foraging and migratory performance in swans infected with low-pathogenic avian influenza A virus. Public Library of Science 2: e184.
Varghese, JN, Laver, WG and Colman, PM (1983). Structure of the influenza virus glycoprotein antigen neuraminidase at 2.9 A resolution. Nature 303: 3540.
Varki, A (2001). N-glycolylneuraminic acid deficiency in humans. Biochimie 83: 615622.
Vines, A, Wells, K, Matrosovich, M, Castrucci, MR, Ito, T and Kawaoka, Y (1998). The role of influenza A virus hemagglutinin residues 226 and 228 in receptor specificity and host range restriction. Journal of Virology 72: 76267631.
Wagner, R, Wolff, T, Herwig, A, Pleschka, S and Klenk, HD (2000). Interdependence of hemagglutinin glycosylation and neuraminidase as regulators of influenza virus growth: a study by reverse genetics. Journal of Virology 74: 63166323.
Wain-Hobson, S, Vartanian, JP, Henry, M, Chenciner, N, Cheynier, R, Delassus, S, Martins, LP, Sala, M, Nugeyre, MT, Guetard, D, Klatzmann, D, Gluckman, JC, Rozenbaum, W, Barré-Sinoussi, F and Montagnier, L (1991). LAV revisited: origins of the early HIV-1 isolates from Institut Pasteur. Science 252: 961965.
Wan, H and Perez, DR (2006). Quail carry sialic acid receptors compatible with binding of avian and human influenza viruses. Virology 346: 278286.
Wang, C, Takeuchi, K, Pinto, LH and Lamb, RA (1993). Ion channel activity of influenza A virus M2 protein: characterization of the amantadine block. Journal of Virology 67: 55855594.
Webby, RJ and Webster, RG (2001). Emergence of influenza A viruses. Philosophical Transactions of the Royal Society of London – Series B: Biological Sciences 356: 18171828.
Webby, RJ, Swenson, SL, Krauss, SL, Gerrish, PJ, Goyal, SM and Webster, RG (2000). Evolution of swine H3N2 influenza viruses in the United States. Journal of Virology 74: 82438251.
Webby, RJ, Rossow, K, Erickson, G, Sims, Y and Webster, R (2004). Multiple lineages of antigenically and genetically diverse influenza A virus co-circulate in the United States swine population. Virus Research 103: 6773.
Webster, RG (1993). Are equine 1 influenza viruses still present in horses? Equine Veterinary Journal 25: 537538.
Webster, RG (1997). Influenza virus: transmission between species and relevance to emergence of the next human pandemic. Archives of Virology – Supplementum 13: 105113.
Webster, RG (1998). Influenza: an emerging disease. Emerging Infectious Diseases 4: 436441.
Webster, RG, Yakhno, M, Hinshaw, VS, Bean, WJ and Murti, KG (1978). Intestinal influenza: replication and characterization of influenza viruses in ducks. Virology 84: 268278.
Webster, RG, Geraci, J, Petursson, G and Skirnisson, K (1981). Conjunctivitis in human beings caused by influenza A virus of seals. New England Journal of Medicine 304: 911.
Webster, RG, Bean, WJ, Gorman, OT, Chambers, TM and Kawaoka, Y (1992). Evolution and ecology of influenza A viruses. Microbiological Reviews 56: 152179.
Webster, RG, Wright, SM, Castrucci, MR, Bean, WJ and Kawaoka, Y (1993). Influenza – a model of an emerging virus disease. Intervirology 35: 1625.
Webster, RG, Guan, Y, Poon, L, Krauss, S, Webby, R, Govorkovai, E and Peiris, M (2005). The spread of the H5N1 bird flu epidemic in Asia in 2004. Archives of Virology – Supplementum 19: 117129.
Wentworth, DE, Thompson, BL, Xu, X, Regnery, HL, Cooley, AJ, McGregor, MW, Cox, NJ and Hinshaw, VS (1994). An influenza A (H1N1) virus, closely related to swine influenza virus, responsible for a fatal case of human influenza. Journal of Virology 68: 20512058.
Wentworth, DE, McGregor, MW, Macklin, MD, Neumann, V and Hinshaw, VS (1997). Transmission of swine influenza virus to humans after exposure to experimentally infected pigs. Journal of Infectious Diseases 175: 715.
Wharton, SA, Weis, W, Skehel, JJ and Wiley, DC (1989). Structure, Function, and Antigenicity of the Hemagglutinin of Influenza Virus. New York: Plenum Press.
Wilson, IA, Skehel, JJ and Wiley, DC (1981). Structure of the haemagglutinin membrane glycoprotein of influenza virus at 3 A resolution. Nature 289: 366373.
Wilson, WD (1993). Equine influenza. Veterinary Clinics of North America – Equine Practice 9: 257282.
Wolf, YI, Viboud, C, Holmes, EC, Koonin, EV and Lipman, DJ (2006). Long intervals of stasis punctuated by bursts of positive selection in the seasonal evolution of influenza A virus. Biology Direct 1: 34.
Wolff, T, O'Neill, RE and Palese, P (1996). Interaction cloning of NS1-I, a human protein that binds to the nonstructural NS1 proteins of influenza A and B viruses. Journal of Virology 70: 53635372.
Wolff, T, O'Neill, RE and Palese, P (1998). NS1-binding protein (NS1-BP): a novel human protein that interacts with the influenza A virus nonstructural NS1 protein is relocalized in the nuclei of infected cells. Journal of Virology 72: 71707180.
Wright, PF and Webster, RG (2006). Orthomyxoviruses. Philadelphia, PA: Lippincott Williams and Wilkins.
Xu, C, Fan, W, Wei, R and Zhao, H (2004). Isolation and identification of swine influenza recombinant A/Swine/Shandong/1/2003(H9N2) virus. Microbes and Infection 6: 919925.
Yamada, S, Suzuki, Y, Suzuki, T, Le, MQ, Nidom, CA, Sakai-Tagawa, Y, Muramoto, Y, Ito, M, Kiso, M, Horimoto, T, Shinya, K, Sawada, T, Kiso, M, Usui, T, Murata, T, Lin, Y, Hay, A, Haire, LF, Stevens, DJ, Russell, RJ, Gamblin, SJ, Skehel, JJ and Kawaoka, Y (2006). Haemagglutinin mutations responsible for the binding of H5N1 influenza A viruses to human-type receptors. Nature 444: 378382.
Yasuda, J, Nakada, S, Kato, A, Toyoda, T and Ishihama, A (1993). Molecular assembly of influenza virus: association of the NS2 protein with virion matrix. Virology 196: 249255.
Yingst, SL, Saad, MD and Felt, SA (2006). Qinghai-like H5N1 from domestic cats, northern Iraq. Emerging Infectious Diseases 12: 12951297.
Zhou, NN, Senne, DA, Landgraf, JS, Swenson, SL, Erickson, G, Rossow, K, Liu, L, Yoon, K, Krauss, S and Webster, RG (1999a). Genetic reassortment of avian, swine, and human influenza A viruses in American pigs. Journal of Virology 73: 88518856.
Zhou, NN, Shortridge, KF, Claas, EC, Krauss, SL and Webster, RG (1999b). Rapid evolution of H5N1 influenza viruses in chickens in Hong Kong. Journal of Virology 73: 33663374.