An overview of the characteristics of the novel avian influenza A H7N9 virus in humans

Frontiers in Microbiology

Volumn 6, Issue MAR, 2015, Pages

  Tan, Kei Xian ^a   Jacob, Sabrina A ^a   Chan, Kok Gan ^b   Lee, Learn Han ^a  

^a MONASH UNIVERSITY MALAYSIA   (Malaysia)

^b UNIVERSITY OF MALAYA   (Malaysia)

Author keywords

Avian influenza A; Characteristics; H7N9; Novel; Virus

Indexed keywords

AMANTADINE; AMINOTRANSFERASE; C REACTIVE PROTEIN; CREATINE KINASE; CREATINE KINASE ISOENZYME; HEMAGGLUTININ; LACTATE DEHYDROGENASE; NONSTRUCTURAL PROTEIN 1; OSELTAMIVIR; PERAMIVIR; RIMANTADINE; SIALIC ACID; SIALIDASE; VIRUS PROTEIN; ZANAMIVIR;

AVIAN INFLUENZA; BINDING AFFINITY; DISEASE TRANSMISSION; DRUG EFFICACY; GENE MUTATION; GENETIC ANALYSIS; GEOGRAPHIC DISTRIBUTION; HUMAN; INFLUENZA VIRUS A H7N9; NONHUMAN; PHYLOGENY; REVIEW; VIRAL GENETICS; VIROLOGY; VIRUS CELL INTERACTION; VIRUS ISOLATION; VIRUS LOAD; VIRUS REPLICATION; VIRUS TRANSMISSION; VIRUS VIRULENCE;

AVES; INFLUENZA A VIRUS;

EID: 84927168737     PISSN: None     EISSN: 1664302X     Source Type: Journal    
DOI: 10.3389/fmicb.2015.00140     Document Type: Review

References (104)

1. Bingsheng, K., and Yijun, H. (2007). Poultry in the 21st century. Poultry Sector in China: Structural Changes during the Past Decade and Future Trends [Online]. Food and Agriculture Organization of the United Nations. Available at: http://www.fao.org/ag/AGAinfo///home/events/bangkok2007/docs/part1/1_3.pdf [accessed April 20, 2013].
2. Butler, D. (2013). Mapping the H7N9 avian flu outbreaks. Nature, 24th April. doi: 10.1038/nature.2013.12863.
3. CDC. (2014). Avian Influenza A (H7N9) Virus. Available at: http://www.cdc.gov/flu/avianflu/h7n9-virus.htm [accessed December 30, 2014].
4. Chang, S. Y., Lin, P. H., Tsai, J. C., Hung, C. C., and Chang, S. C. (2013). The first case of H7N9 influenza in Taiwan. Lancet 381, 1621. doi: 10.1016/S0140-6736(13)60943-5.
5. Chemaly, R. F., Vigil, K. J., Saad, M., Vilar-Compte, D., Cornejo-Juarez, P., Perez-Jimenez, C., et al. (2012). A multicenter study of pandemic influenza a (H1N1) infection in patients with solid tumors in 3 countries. Cancer 118, 4627-4633. doi: 10.1002/cncr.27447.
6. Chen, Y., Liang, W., Yang, S., Wu, N., Gao, H., Sheng, J., et al. (2013). Human infections with the emerging avian influenza a H7N9 virus from wet market poultry: clinical analysis and characterisation of viral genome. Lancet 381, 1916-1925. doi: 10.1016/s0140-6736(13)60903-4.
7. Chowell, G., Simonsen, L., Towers, S., Miller, M., and Viboud, C. (2013). Transmission potential of influenza A/H7N9, February to May 2013, China. BMC Med. 11:214. doi: 10.1186/1741-7015-11-214.
8. Chutinimitkul, S., van Riel, D., Munster, V. J., van den Brand, J. M., Rimmelzwaan, G. F., Kuiken, T., et al. (2010). In vitro assessment of attachment pattern and replication efficiency of H5N1 influenza a viruses with altered receptor specificity. J. Virol. 84, 6825-6833. doi: 10.1128/JVI.02737-09.
9. Connor, R. J., Kawaoka, Y., Webster, R. G., and Paulson, J. C. (1994). Receptor specificity in human, avian, and equine H2 and H3 influenza virus isolates. Virology 205, 17-23. doi: 10.1006/viro.1994.1615.
10. Cowling, B. J., Chan, K. H., Fang, V. J., Lau, L. L. H., So, H. C., Fung, R. O. P., et al. (2010). Comparative epidemiology of pandemic and seasonal influenza a in households. N. Engl. J. Med. 362, 2175-2184. doi: 10.1056/NEJMoa0911530.
11. Cowling, B. J., Jin, L., Lau, E. H. Y., Liao, Q., Wu, P., Jiang, H., et al. (2013). Comparative epidemiology of human infections with avian influenza a H7N9 and H5N1 viruses in China: a population-based study of laboratory-confirmed cases. Lancet 382, 129-137. doi: 10.1016/s0140-6736(13)61171-x.
12. Dortmans, J. C. F. M., Dekkers, J., Wickramasinghe, I. N. A., Verheije, M. H., Rottier, P. J. M., Van Kuppeveld, F. J. M., et al. (2013). Adaptation of novel H7N9 influenza a virus to human receptors. Sci. Rep. 3, 3058. doi: 10.1038/srep03058.
13. Fan, S., Deng, G., Song, J., Tian, G., Suo, Y., Jiang, Y., et al. (2009). Two amino acid residues in the matrix protein M1 contribute to the virulence difference of H5N1 avian influenza viruses in mice. Virology 38, 28-32. doi: 10.1016/j.virol.2008.11.044.
14. Gambaryan, A. S., Matrosovich, T. Y., Philipp, J., Munster, V. J., Fouchier, R. A., Cattoli, G., et al. (2012). Receptor-binding profiles of H7subtype influenza viruses in different host species. J. Virol. 86, 4370-4379. doi: 10.1128/JVI.06959-11.
15. Gao, H.-N., Lu, H.-Z., Cao, B., Du, B., Shang, H., Gan, J.-H., et al. (2013a). Clinical findings in 111 cases of influenza a (H7N9) virus infection. N. Engl. J. Med. 368, 2277-2285. doi: 10.1056/NEJMoa1305584.
16. Gao, R., Cao, B., Hu, Y., Feng, Z., Wang, D., Hu, W., et al. (2013b). Human infection with a novel avian-origin influenza a (H7N9) virus. N. Engl. J. Med. 368, 1888-1897. doi: 10.1056/NEJMoa1304459.
17. Gao, Y., Zhang, Y., Shinya, K., Deng, G., Jiang, Y., Li, Z., et al. (2009). Identification of amino acids in HA and PB2 critical for the transmission of H5N1 avian influenza viruses in a mammalian host. PLoS Pathog. 5:e1000709. doi: 10.371/journal.ppat.1000709.
18. Govorkova, E. A. (2013). Consequences of resistance: in vitro fitness, in vivo infectivity, and transmissibility of oseltamivir-resistant influenza A viruses. Influenza Other Respir. Viruses 7, 50-57. doi: 10.1111/irv.12044.
19. Gubareva, L. V., Robinson, M. J., Bethell, R. C., and Webster, R. G. (1997). Catalytic and framework mutations in the neuraminidase active site of influenza viruses that are resistant to 4-guanidino-Neu5Ac2en. J. Virol. 71, 3385-3390.
20. Ha, Y., Stevens, D. J., Skehel, J. J., and Wiley, D. C. (2001). X-ray structures of H5 avian and H9 swine influenza virus hemagglutinins bound to avian and human receptor analogs. Proc. Natl. Acad. Sci. U.S.A. 98, 11181-11186. doi: 10.1073./pnas.201401198.
21. Hai, R., Schmolke, M., Leyva-Grado, V. H., Thangavel, R. R., Margine, I., Jaffe, E. L., et al. (2013). Influenza A(H7N9) virus gains neuraminidase inhibitor resistance without loss of in vivo virulence or transmissibility. Nat. Commun. 4, 2854. doi: 10.1038/ncomms3854.
22. Hatta, M., Gao, P., Halfmann, P., and Kawaoka, Y. (2001). Molecular basis for high virulence of Hong Kong H5N1 influenza A viruses. Science 293, 1840-1842. doi: 10.1126/science.1062882.
23. Hay, A. J., Wolstenholme, A. J., Skehel, J. J., and Smith, M. H. (1985). The molecular basis of the specific anti-influenza action of amantadine. EMBO J. 4, 3021-3024.
24. Hayden, F. G., Fritz, R., Lobo, M. C., Alvord, W., Strober, W., and Straus, S. E. (1998). Local and systemic cytokine responses during experimental human influenza A virus infection. Relation to symptom formation and host defense. J. Clin. Invest. 101, 643-649. doi: 10.1172/JCI1355.
25. Hayden, F. G., Osterhaus, A. D. M. E., Treanor, J. J., Fleming, D. M., Aoki, F. Y., Nicholson, K. G., et al. (1997). Efficacy and safety of the neuraminidase inhibitor zanamivir in the treatment of influenzavirus infections. N. Engl. J. Med. 337, 874-880. doi: 10.1056/NEJM199709253371302.
26. Hayden, F. G., Treanor, J. J., Fritz, R., Lobo, M., Belts, R. F., Miller, M., et al. (1999). Use of the oral neuraminidase inhibitor oseltamivir in experimental human influenza: randomized controlled trials for prevention and treatment. JAMA 282, 1240-1246. doi: 10.1001/jama.282.13.1240.
27. Hedrick, J. A., Barzilai, A., Behre, U., Henderson, F. W., Hammond, J., Reilly, L., et al. (2000). Zanamivir for treatment of symptomatic influenza A and B infection in children five to twelve years of age: a randomized controlled trial. Pediatr. Infect. Dis. J. 19, 410-417. doi: 10.1097/00006454-200005000-00005.
28. Heinonen, S., Silvennoinen, H., Lehtinen, P., Vainionpää, R., Vahlberg, T., Ziegler, T., et al. (2010). Early oseltamivir treatment of influenza in children 1-3 years of age: a randomized controlled trial. Clin. Infect. Dis. 51, 887-894. doi: 10.1086/656408.
29. Hernán, M. A., and Lipsitch, M. (2011). Oseltamivir and risk of lower respiratory tract complications in patients with flu symptoms: a meta-analysis of eleven randomized clinical trials. Clin. Infect. Dis. 53, 277-279. doi: 10.1093/cid/cir400.
30. Herfst, S., Schrauwen, E. J., Linster, M., Chutinimitkul, S., de Wit, E., Munster, V. J., et al. (2012). Airborne transmission of influenza A/H5N1 virus between ferrets. Science 336, 1534-1541. doi: 10.1126/science.1213362.
31. Hiba, V., Chowers, M., Levi-Vinograd, I., Rubinovitch, B., Leibovici, L., and Paul, M. (2011). Benefit of early treatment with oseltamivir in hospitalized patients with documented 2009 influenza A (H1N1): retrospective cohort study. J. Antimicrob. Chemother. 66, 1150-1155. doi: 10.1093/jac/dkr089.
32. Hsu, J., Santesso, N., Mustafa, R., Brozek, J., Chen, Y. L., Hopkins, J. P., et al. (2012). Antivirals for treatment of influenza systematic review and meta-analysis of observational studies. Ann. Intern. Med. 156, 512-524. doi: 10.7326/0003-4819-156-7-201204030-00411.
33. Hu, Y., Lu, S., Song, Z., Wang, W., Hao, P., Li, J., et al. (2013). Association between adverse clinical outcome in human disease caused by novel influenza A H7N9 virus and sustained viral shedding and emergence of antiviral resistance. Lancet 381, 2273-2279. doi: 10.1016/S0140-6736(13)61125-3.
34. Jackson, D., Hossain, M. J., Hickman, D., Perez, D. R., and Lamb, R. A. (2008). A new influenza virus virulence determinant: the NS1 protein four C-terminal residues modulate pathogenicity. Proc. Natl. Acad. Sci. U.S.A 105, 4381-4386. doi: 10.1073/pnas.0800482105.
35. Jain, S., Kamimoto, L., Bramley, A. M., Schmitz, A. M., Benoit, S. R., Louie, J., et al. (2009). Hospitalized patients with 2009 H1N1 influenza in the United States, April-June 2009. N. Engl. J. Med. 361, 1935-1944. doi: 10.1056/NEJMoa0906695.
36. Jiao, P., Tian, G., Li, Y., Deng, G., Jiang, Y., Liu, C., et al. (2008). A single-amino-acid substitution in the NS1 protein changes the pathogenicity of H5N1 avian influenza viruses in mice. J. Virol. 82, 1146-1154. doi: 10.1128/JVI.00376.
37. Kageyama, T., Fujisaki, S., Takashita, E., Xu, H., Yamada, S., Uchida, Y., et al. (2013). Genetic analysis of novel avian A(H7N9) influenza viruses isolated from patients in China, February to April 2013. Euro surveill. 18, 20453.
38. Kim, H. R., Park, C. K., Lee, Y. J., Oem, J. K., Kang, H. M., Choi, J. G., et al. (2012). Low pathogenic H7 subtype avian influenza viruses isolated from domestic ducks in South Korea and the close association with isolates of wild birds. J. Gen. Virol. 93, 1278-1287. doi: 10.1099/vir.0.041269-0.
39. Kim, J. H., Skountzou, I., Compans, R., and Jacob, J. (2009). Original antigenic sin responses to influenza viruses. J. Immunol. 183, 3294-3301. doi: 10.4049/jimmunol.0900398.
40. Knepper, J., Schierhorn, K., Becher, A., Budt, M., Tönnies, M., Bauer, T., et al. (2013). The novel human influenza A(H7N9) virus is naturally adapted to efficient growth in human lung tissue. mBio 4, e00601-e00613. doi: 10.1128/mBio.00601-13.
41. Kumar, A. (2011). Early versus late oseltamivir treatment in severely ill patients with 2009 pandemic influenza A (H1N1): speed is life. J. Antimicrob. Chemother. 66, 959-963. doi: 10.1093/jac/dkr090.
42. Labadie, K., Dos Santos Afonso, E., Rameix-Welti, M. A., van der Werf, S., and Naffakh, N. (2007). Host-range determinants on the PB2 protein of influenza A viruses control the interaction between the viral polymerase and nucleoprotein in human cells. Virology 362, 271-282. doi: 10.1016/j.virol.2006.12.027.
43. Lalezari, J., Campion, K., Keene, O., and Silagy, C. (2001). Zanamivir for the treatment of influenza a and b infection in high-risk patients: a pooled analysis of randomized controlled trials. Arch. Intern. Med. 161, 212-217. doi: 10.1001/archinte.161.2.212.
44. Lamb, R. A., and Choppin, P. W. (1983). The gene structure and replication of influenza virus. Annu. Rev. Biochem. 52, 467-506. doi: 10.1146/annurev.bi.52.070183.002343.
45. Li, Q., Zhou, L., Zhou, M., Chen, Z., Li, F., Wu, H., et al. (2014). Epidemiology of human infections with avian influenza A(H7N9) virus in china. N. Engl. J. Med. 370, 520-532. doi: 10.1056/NEJMoa1304617.
46. Li, Z., Chen, H., Jiao, P., Deng, G., Tian, G., Li, Y., et al. (2005). Molecular basis of replication of duck H5N1 influenza viruses in a mammalian mouse model. J. Virol. 79, 12058-12064. doi: 10.1128/JVI.79.18.12058-12064.2005.
47. Lin, P.-H., Chao, T.-L., Kuo, S.-W., Wang, J.-T., Hung, C.-C., Lin, H.-C., et al. (2014). Virological, serological, and antiviral studies in an imported human case of avian influenza A(H7N9) virus in taiwan. Clin. Infect. Dis. 58, 242-246. doi: 10.1093/cid/cit638.
48. Liu, D., Shi, W., Shi, Y., Wang, D., Xiao, H., Li, W., et al. (2013a). Origin and diversity of novel avian influenza A H7N9 viruses causing human infection: phylogenetic, structural, and coalescent analyses. Lancet 381, 1926-1932. doi: 10.1016/S0140-6736(13)60938-1.
49. Liu, S., Sun, J., Cai, J., Miao, Z., Lu, M., Qin, S., et al. (2013b). Epidemiological, clinical and viral characteristics of fatal cases of human avian influenza A (H7N9) virus in Zhejiang Province, China. J. Infect. 67, 595-605. doi: 10.1016/j.jinf.2013.08.007.
50. Liu, W., Yang, K., Qi, X., Xu, K., Ji, H., Ai, J., et al. (2013c). Spatial and temporal analysis of human infection with avian influenza A(H7N9) virus in China, 2013. Euro Surveill. 18, 20640. doi: 10.1056/NEJMoa1304459.
51. Louie, J. K., Yang, S., Acosta, M., Yen, C., Samuel, M. C., Schechter, R., et al. (2012). Treatment with neuraminidase inhibitors for critically ill patients with influenza A (H1N1)pdm09. Clin. Infect. Dis. 55, 1198-1204. doi: 10.1093/cid/cis636.
52. Lu, S., Xi, X., Zheng, Y., Cao, Y., Liu, X., and Lu, H. (2013). Analysis of the clinical characteristics and treatment of two patients with avian influenza virus (H7N9). BioSci. Trends 7, 109-112. doi: 10.5582/bst.2013.v7.2.109.
53. 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. J. Virol. 73, 1146-1155.
54. McKimm-Breschkin, J. L. (2013). Influenza neuraminidase inhibitors: antiviral action and mechanisms of resistance. Influenza Other Respir. Viruses 7, 25-36. doi: 10.1111/irv.12047.
55. McKimm-Breschkin, J. L., Sahasrabudhe, A., Blick, T. J., McDonald, M., Colman, P. M., and Hart, G. L., et al. (1998). Mutations in a conserved residue in the influenza virus neuraminidase active site decreases sensitivity to Neu5Ac2en-derived inhibitors. J. Virol. 72, 2456-2462.
56. McKimm-Breschkin, J., Trivedi, T., Hampson, A., Hay, A., Klimov, A., Tashiro, M., et al. (2003). Neuraminidase sequence analysis and susceptibilities of influenza virus clinical isolates to zanamivir and oseltamivir. Antimicrob. Agents Chemother. 47, 2264-2272. doi: 10.1128/AAC.47.7.2264-2272.2003.
57. Mei, Z., Lu, S., Wu, X., Shao, L., Hui, Y., Wang, J., et al. (2013). Avian influenza A(H7N9) virus infections, Shanghai, China. Emerg. Infect. Dis. 19, 1179-1181. doi: 10.3201/eid1907.130523.
58. Monto, A. S., Fleming, D. M., Henry, D., De Groot, R., Makela, M., Klein, T., et al. (1999). Efficacy and safety of the neuraminidase inhibitor zanamivir in the treatment of influenza A and B virus infections. J. Infect. Dis. 180, 254-261. doi: 10.1086/314904.
59. Murhekar, M., Arima, Y., Horby, P., Vandemaele, K. A., Vong, S., Zijian, F., et al. (2013). Avian influenza A(H7N9) and the closure of live bird markets. WPSAR 4, 4-7. doi: 10.5365/wpsar.2013.4.2.008.
60. Muthuri, S. G., Myles, P. R., Venkatesan, S., Leonardi-Bee, J., and Nguyen-Van-Tam, J. S. (2013). Impact of neuraminidase inhibitor treatment on outcomes of public health importance during the 2009-2010 influenza A(H1N1) pandemic: a systematic review and Meta-Analysis in Hospitalized Patients. J. Infect. Dis. 207, 553-563. doi: 10.1093/infdis/jis726.
61. Nagy, A., Cerníková, L., Krivda, V., and Hornícková, J. (2012). Digital genotyping of avian influenza viruses of H7 subtype detected in central Europe in 2007-2011. Virus Res. 165, 126-133. doi: 10.1016/j.virusres.2012.02.005.
62. Neumann, G., Macken, C. A., Karasin, A. I., Fouchier, R. A., and Kawaoka, Y. (2012). Egyptian H5N1 influenza viruses-cause for concern? PLoS Pathog. 8:e1002932. doi: 10.371/journal.ppat.1002932.
63. Nicholson, K. G., Aoki, F. Y., Osterhaus, A., Trottier, S., Carewicz, O., Mercier, C. H., et al. (2000). Efficacy and safety of oseltamivir in treatment of acute influenza: a randomised controlled trial. Lancet 355, 1845-1850. doi: 10.1016/s0140-6736(00)02288-1.
64. Pasick, J., Pedersen, J., and Hernandez, M. S. (2012). Avian influenza in North America, 2009-2011. Avian. Dis. 56, 845-848. doi: 10.1637/10206-041512-Reg.1.
65. Peng, Y., Xinghuo, P., Ying, D., Chunna, M., Daitao, Z., Ying, S., et al. (2013). Surveillance for Avian Influenza A(H7N9), Beijing, China, 2013. Emerg. Infect. Dis. 19, 2041. doi: 10.3201/eid1912.130983.
66. Pinto, L. H., Holsinger, L. J., and Lamb, R. A. (1992). Influenza virus M2 protein has ion channel activity. Cell 69, 517-528. doi: 10.1016/0092-8674(92)90452-I.
67. Qi, X., Qian, Y.-H., Bao, C.-J., Guo, X.-L., Cui, L.-B., Tang, F.-Y., et al. (2013). Probable person to person transmission of novel avian influenza A (H7N9) virus in Eastern China, 2013: epidemiological investigation. BMJ 347, f4752. doi: 10.1136/bmj.f4752.
68. Qi, Y., Fan, H., Qi, X., Zhu, Z., Guo, X., Chen, Y., et al. (2014). A novel pyrosequencing assay for the detection of neuraminidase inhibitor resistance-conferring mutations among clinical isolates of avian H7N9 influenza virus. Virus Res. 179, 119-124. doi: 10.1016/j.virusres.2013.10.026.
69. Ramos, I., Krammer, F., Hai, R., Aguilera, D., Bernal-Rubio, D., Steel, J., et al. (2013). H7N9 influenza viruses interact preferentially with a2, 3-linked sialic acids and bind weakly to a2, 6-linked sialic acids. J. Gen. Virol. 94, 2417-2423. doi: 10.1099/vir.0.056184-0.
70. Richard, M., Schrauwen, E. J. A., De Graaf, M., Bestebroer, T. M., Spronken, M. I. J., Van Boheemen, S., et al. (2013). Limited airborne transmission of H7N9 influenza A virus between ferrets. Nature 501, 560-563. doi: 10.1038/nature12476.
71. Rodríguez, A., Díaz, E., Martín-Loeches, I., Sandiumenge, A., Canadell, L., Díaz, J. J., et al. (2011). Impact of early oseltamivir treatment on outcome in critically ill patients with 2009 pandemic influenza A. J. Antimicrob. Chemother. 66, 1140-1149. doi: 10.1093/jac/dkq511.
72. Sato, M., Hosoya, M., Kato, K., and Suzuki, H. (2005). Viral shedding in children with influenza virus infections treated with neuraminidase inhibitors. Pediatr. Infect. Dis. J. 24, 931-932. doi: 10.1097/01.inf.0000180976.81055.ce.
73. Senne, D. A., Panigrahy, B., Kawaoka, Y., Pearson, J. E., Süss, J., Lipkind, M., et al. (1996). Survey of the hemagglutinin (HA) cleavage site sequence of H5 and H7 avian influenza viruses: amino acid sequence at the HA cleavage site as a marker of pathogenicity potential. Avian. Dis. 40, 425-437. doi: 10.2307/1592241.
74. Shen, Z., Chen, Z., Li, X., Xu, L., Guan, W., Cao, Y., et al. (2014). Host immunological response and factors associated with clinical outcome in patients with the novel influenza A H7N9 infection. Clin. Microbiol. Infec. 20, O493-O500. doi: 10.1111/1469-0691.12505.
75. Shi, J., Deng, G., Liu, P., Zhou, J., Guan, L., Li, W., et al. (2013a). Isolation and characterization of H7N9 viruses from live poultry markets-Implication of the source of current H7N9 infection in humans. Chin. Sci. Bull. 58, 1857-1863. doi: 10.1007/s11434-013-5873-4.
76. Shi, J., Xie, J., He, Z., Hu, Y., He, Y., Huang, Q., et al. (2013b). A detailed epidemiological and clinical description of 6 human cases of avian-origin influenza a (H7N9) virus infection in shanghai. PLoS ONE 8:e77651. doi: 10.1371/journal.pone.0077651.
77. Shi, Y., Zhang, W., Wang, F., Qi, J., Wu, Y., Song, H., et al. (2013c). Structures and receptor binding of hemagglutinins from human-infecting H7N9 influenza viruses. Science 342, 243-247. doi: 10.1126/science.1242917.
78. Siston, A. M., Rasmussen, S. A., Honein, M. A., Fry, A. M., Seib, K., Callaghan, W. M., et al. (2010). Pandemic 2009 influenza a(h1n1) virus illness among pregnant women in the united states. JAMA 303, 1517-1525. doi: 10.1001/jama.2010.479.
79. Skowronski, D., Janjua, N. Z., Kwindt, T. L., and De Serres, G. (2013). Virus-host interactions and the unusual age and sex distribution of human cases of influenza A(H7N9) in China, April 2013. Euro. Surveill. 18, 20465.
80. Subbarao, K., Chen, H., Swayne, D., Mingay, L., Fodor, E., Brownlee, G., et al. (2003). Evaluation of a genetically modified reassortant H5N1 influenza a virus vaccine candidate generated by plasmid-based reverse genetics. Virology 305, 192-200. doi: 10.1006/viro.2002.1742.
81. Swayne, D. E. (2012). Impact of vaccines and vaccination on Global Control of Avian Influenza. Avian. Dis. 56, 818-828. doi: 10.1637/10183-041012-Review.1.
82. Tharakaraman, K., Jayaraman, A., Raman, R., Viswanathan, K., Stebbins, N. W., Johnson, D., et al. (2013). Glycan-receptor binding of the influenza a Virus H7N9 hemagglutinin. Cell 153, 1486-1493. doi: 10.1016/j.cell.2013.05.034.
83. To, K. K. W., Chan, J. F. W., Chen, H., Li, L., and Yuen, K.-Y. (2013). The emergence of influenza A H7N9 in human beings 16 years after influenza A H5N1: a tale of two cities. Lancet Infect. Dis. 13, 809-821. doi: 10.1016/s1473-3099(13)70167-1.
84. Treanor, J. J., Hayden, F. G., Vrooman, P. S., Barbarash, R., Bettis, R., Riff, D., et al. (2000). Efficacy and safety of the oral neuraminidase inhibitor oseltamivir in treating acute influenza: a randomized controlled trial. JAMA 283, 1016-1024. doi: 10.1001/jama.283.8.1016.
85. van Riel, D., Leijten, L. M. E., De Graaf, M., Siegers, J. Y., Short, K. R., Spronken, M. I. J., et al. (2013). Novel avian-origin influenza A (H7N9) virus attaches to epithelium in both upper and lower respiratory tract of humans. Am. J. Pathol. 183, 1137-1143. doi: 10.1016/j.ajpath.2013.06.011.
86. Wang, W., Lu, B., Zhou, H., Suguitan, A. L. Jr., Cheng, X., Subbarao, K., et al. (2010). Glycosylation at 158N of the hemagglutinin protein and receptor binding specificity synergistically affect the antigenicity and immunogenicity of a live attenuated H5N1 A/Vietnam/1203/2004 vaccine virus in ferrets. J. Virol. 84, 6570-6577. doi: 10.1128/JVI.00221-10.
87. Watanabe, T., Kiso, M., Fukuyama, S., Nakajima, N., Imai, M., Yamada, S., et al. (2013). Characterization of H7N9 influenza a viruses isolated from humans. Nature 501, 551-555. doi: 10.1038/nature12392.
88. Watanabe, T., Watanabe, S., Maher, E. A., Neumann, G., and Kawaoka, Y. (2014). Pandemic potential of avian influenza A (H7N9) viruses. Trends Microbiol. 22, 623-631. doi: 10.1016/j.tim.2014.08.008.
89. Whitley, R. J., Hayden, F. G., Reisinger, K. S., Young, N., Dutkowski, R., Ipe, D., et al. (2001). Oral oseltamivir treatment of influenza in children. Pediatr. Infect. Dis. J. 20, 127-133. doi: 10.1097/00006454-200102000-00002.
90. WHO. (2013). Overview of the Emergence and Characteristics of the Avian Influenza A (H7N9) virus. Geneva: World Health Organization.
91. Wu, Y., Bi, Y., Vavricka, C. J., Sun, X., Zhang, Y., Gao, F., et al. (2013). Characterization of two distinct neuraminidases from avian-origin human-infecting H7N9 influenza viruses. Cell Res. 23, 1347-1355. doi: 10.1038/cr.2013.144.
92. Xiong, C., Zhang, Z., Jiang, Q., and Chen, Y. (2013a). Evolutionary characteristics of A/Hangzhou/1/2013 and source of avian influenza virus H7N9 subtype in China. Clin. Infect. Dis. 57, 622-624. doi: 10.1093/cid/cit294.
93. Xiong, X., Martin, S. R., Haire, L. F., Wharton, S. A., Daniels, R. S., Bennett, M. S., et al. (2013b). Receptor binding by an H7N9 influenza virus from humans. Nature 499, 496-499. doi: 10.1038/nature12372.
94. Xu, J., Lu, S., Wang, H., and Chen, C. (2013a). Reducing exposure to avian influenza H7N9. Lancet 381, 1815-1816. doi: 10.1016/S0140-6736(13)60950-2.
95. Xu, C., Havers, F., Wang, L., Chen, T., Shi, J., Wang, D., et al. (2013b). Monitoring avian influenza A(H7N9) virus through national influenza-like illness surveillance, China. Emerg. Infect. Dis. 19, 2013. doi: 10.3201/eid1908.130662.
96. Yen, H.-L., Mckimm-Breschkin, J. L., Choy, K.-T., Wong, D. D. Y., Cheung, P. P. H., Zhou, J., et al. (2013). Resistance to neuraminidase inhibitors conferred by an R292K mutation in a human influenza virus H7N9 isolate can be masked by a mixed R/K viral population. mBio 4, e00396-e00413. doi: 10.1128/mBio.00396-13.
97. Yu, H., Cowling, B. J., Feng, L., Lau, E. H. Y., Liao, Q., Tsang, T. K., et al. (2013). Human infection with avian influenza A H7N9 virus: an assessment of clinical severity. Lancet 382, 138-145. doi: 10.1016/s0140-6736(13)61207-6.
98. Yu, H., Feng, Z., Uyeki, T. M., Liao, Q., Zhou, L., Feng, L., et al. (2011). Risk factors for severe illness with 2009 pandemic influenza A (H1N1) virus infection in China. Clin. Infect. Dis. 52, 457-465. doi: 10.1093/cid/ciq144.
99. Yu, H., Liao, Q., Yuan, Y., Zhou, L., Xiang, N., Huai, Y., et al. (2010). Effectiveness of oseltamivir on disease progression and viral RNA shedding in patients with mild pandemic 2009 influenza A H1N1: opportunistic retrospective study of medical charts in China. BMJ 341, c4779. doi: 10.1136/bmj.c4779.
100. Zamarin, D., Ortigoza, M. B., and Palese, P. (2006). Influenza A virus PB1-F2 protein contributes to viral pathogenesis in mice. J. Virol. 80, 7976-7983. doi: 10.1128/JVI.00415.
101. Zheng, B.-J., Chan, K.-W., Lin, Y.-P., Zhao, G.-Y., Chan, C., Zhang, H.-J., et al. (2008). Delayed antiviral plus immunomodulator treatment still reduces mortality in mice infected by high inoculum of influenza A/H5N1 virus. Proc. Natl. Acad. Sci. U.S.A. 105, 8091-8096. doi: 10.1073/pnas.0711942105.
102. Zhu, H., Wang, D., Kelvin, D. J., Li, L., Zheng, Z., Yoon, S.-W., et al. (2013a). Infectivity, Transmission, and Pathology of Human-Isolated H7N9 Influenza Virus in Ferrets and Pigs. Science 341, 183-186. doi: 10.1126/science.1239844.
103. Zhu, Y., Qi, X., Cui, L., Zhou, M., and Wang, H. (2013b). Human co-infection with novel avian influenza A H7N9 and influenza A H3N2 viruses in Jiangsu province, China. Lancet 381, 2134. doi: 10.1016/S0140-6736(13)61135-6.
104. Zhuang, Q., Wang, S., Wu, M., Liu, S., Jiang, W., Hou, G., et al. (2013). Epidemiological and risk analysis of the H7N9 subtype influenza outbreak in China at its early stage. Chin. Sci. Bull. 58, 3183-3187. doi: 10.1007/s11434-013-5880-5.