Advertisement

Why Do Exceptionally Dangerous Gain-of-Function Experiments in Influenza?

  • Marc LipsitchEmail author
Protocol
Part of the Methods in Molecular Biology book series (MIMB, volume 1836)

Abstract

This chapter makes the case against performing exceptionally dangerous gain-of-function experiments that are designed to create potentially pandemic and novel strains of influenza, for example, by enhancing the airborne transmissibility in mammals of highly virulent avian influenza strains. This is a question of intense debate over the last 5 years, though the history of such experiments goes back at least to the synthesis of viable influenza A H1N1 (1918) based on material preserved from the 1918 pandemic. This chapter makes the case that experiments to create potential pandemic pathogens (PPPs) are nearly unique in that they present biosafety risks that extend well beyond the experimenter or laboratory performing them; an accidental release could, as the name suggests, lead to global spread of a virulent virus, a biosafety incident on a scale never before seen. In such cases, biosafety considerations should be uppermost in the consideration of alternative approaches to experimental objectives and design, rather than being settled after the fact, as is appropriately done for most research involving pathogens. The extensive recent discussion of the magnitude of risks from such experiments is briefly reviewed. The chapter argues that, while there are indisputably certain questions that can be answered only by gain-of-function experiments in highly pathogenic strains, these questions are narrow and unlikely to meaningfully advance public health goals such as vaccine production and pandemic prediction. Alternative approaches to experimental influenza virology and characterization of existing strains are in general completely safe, higher throughput, more generalizable, and less costly than creation of PPP in the laboratory and can thereby better inform public health. Indeed, virtually every finding of recent PPP experiments that has been cited for its public health value was predated by similar findings using safe methodologies. The chapter concludes that the unique scientific and public health value of PPP experiments is inadequate to justify the unique risks they entail and that researchers would be well-advised to turn their talents to other methodologies that will be safe and more rewarding scientifically.

Key words

Influenza Gain-of-function Potential pandemic pathogen Ferret Evolution Passage Virulence Transmissibility Selection 

References

  1. 1.
    Duprex WP, Fouchier RA, Imperiale MJ, Lipsitch M, Relman DA (2015) Gain-of-function experiments: time for a real debate. Nat Rev Microbiol 13(1):58–64.  https://doi.org/10.1038/nrmicro3405 CrossRefPubMedGoogle Scholar
  2. 2.
    Fouchier RA (2015) Studies on influenza virus transmission between ferrets: the public health risks revisited. MBio 6(1):e02560.  https://doi.org/10.1128/mBio.02560-14 CrossRefPubMedPubMedCentralGoogle Scholar
  3. 3.
    Butler D (2011) Fears grow over lab-bred flu. Nature 480(7378):421–422.  https://doi.org/10.1038/480421a CrossRefPubMedGoogle Scholar
  4. 4.
    Casadevall A, Howard D, Imperiale MJ (2014) An epistemological perspective on the value of gain-of-function experiments involving pathogens with pandemic potential. MBio 5(5):e01875.  https://doi.org/10.1128/mBio.01875-14 CrossRefPubMedPubMedCentralGoogle Scholar
  5. 5.
    Taubenberger JK, Baltimore D, Doherty PC, Markel H, Morens DM, Webster RG, Wilson IA (2012) Reconstruction of the 1918 influenza virus: unexpected rewards from the past. MBio 3(5):e00201.  https://doi.org/10.1128/mBio.00201-12 CrossRefPubMedPubMedCentralGoogle Scholar
  6. 6.
    Lipsitch M, Galvani A (2014) COMMENTARY: The case against ‘gain-of-function’ experiments: A reply to Fouchier & Kawaoka. CIDRAP June 19 http://www.cidrap.umn.edu/news-perspective/2014/06/commentary-case-against-gain-function-experiments-reply-fouchier-kawaoka. Accessed 18 Nov 2014
  7. 7.
    Lipsitch M, Galvani AP (2014) Ethical alternatives to experiments with novel potential pandemic pathogens. PLoS Med 11(5):e1001646.  https://doi.org/10.1371/journal.pmed.1001646 CrossRefPubMedPubMedCentralGoogle Scholar
  8. 8.
    Herfst S, Schrauwen EJ, Linster M, Chutinimitkul S, de Wit E, Munster VJ, Sorrell EM, Bestebroer TM, Burke DF, Smith DJ, Rimmelzwaan GF, Osterhaus AD, Fouchier RA (2012) Airborne transmission of influenza A/H5N1 virus between ferrets. Science 336(6088):1534–1541.  https://doi.org/10.1126/science.1213362 CrossRefPubMedPubMedCentralGoogle Scholar
  9. 9.
    Imai M, Watanabe T, Hatta M, Das SC, Ozawa M, Shinya K, Zhong G, Hanson A, Katsura H, Watanabe S, Li C, Kawakami E, Yamada S, Kiso M, Suzuki Y, Maher EA, Neumann G, Kawaoka Y (2012) Experimental adaptation of an influenza H5 HA confers respiratory droplet transmission to a reassortant H5 HA/H1N1 virus in ferrets. Nature 486(7403):420–428.  https://doi.org/10.1038/nature10831 CrossRefPubMedPubMedCentralGoogle Scholar
  10. 10.
    Sorrell EM, Wan H, Araya Y, Song H, Perez DR (2009) Minimal molecular constraints for respiratory droplet transmission of an avian-human H9N2 influenza A virus. Proc Natl Acad Sci U S A 106(18):7565–7570.  https://doi.org/10.1073/pnas.0900877106 CrossRefPubMedPubMedCentralGoogle Scholar
  11. 11.
    Kimble JB, Angel M, Wan H, Sutton TC, Finch C, Perez DR (2013) Alternative reassortment events leading to transmissible H9N1 influenza viruses in the ferret model. J Virol 88:66.  https://doi.org/10.1128/JVI.02677-13 CrossRefPubMedGoogle Scholar
  12. 12.
    Zhang Y, Zhang Q, Kong H, Jiang Y, Gao Y, Deng G, Shi J, Tian G, Liu L, Liu J, Guan Y, Bu Z, Chen H (2013) H5N1 hybrid viruses bearing 2009/H1N1 virus genes transmit in Guinea pigs by respiratory droplet. Science 340(6139):1459–1463.  https://doi.org/10.1126/science.1229455 CrossRefPubMedGoogle Scholar
  13. 13.
    Sutton TC, Finch C, Shao H, Angel M, Chen H, Capua I, Cattoli G, Monne I, Perez DR (2014) Airborne transmission of highly pathogenic H7N1 influenza virus in ferrets. J Virol 88(12):6623–6635.  https://doi.org/10.1128/JVI.02765-13 CrossRefPubMedPubMedCentralGoogle Scholar
  14. 14.
    Tumpey TM, Basler CF, Aguilar PV, Zeng H, Solorzano A, Swayne DE, Cox NJ, Katz JM, Taubenberger JK, Palese P, Garcia-Sastre A (2005) Characterization of the reconstructed 1918 Spanish influenza pandemic virus. Science 310(5745):77–80.  https://doi.org/10.1126/science.1119392 CrossRefPubMedGoogle Scholar
  15. 15.
    Enserink M (2004) Virology. tiptoeing around Pandora’s box. Science 305(5684):594–595.  https://doi.org/10.1126/science.305.5684.594 CrossRefPubMedGoogle Scholar
  16. 16.
    Maines TR, Chen LM, Matsuoka Y, Chen H, Rowe T, Ortin J, Falcon A, Nguyen TH, Mai le Q, Sedyaningsih ER, Harun S, Tumpey TM, Donis RO, Cox NJ, Subbarao K, Katz JM (2006) Lack of transmission of H5N1 avian-human reassortant influenza viruses in a ferret model. Proc Natl Acad Sci U S A 103(32):12121–12126.  https://doi.org/10.1073/pnas.0605134103 CrossRefPubMedPubMedCentralGoogle Scholar
  17. 17.
    Maines TR, Chen LM, Belser JA, Van Hoeven N, Smith E, Donis RO, Tumpey TM, Katz JM (2011) Multiple genes contribute to the virulent phenotype observed in ferrets of an H5N1 influenza virus isolated from Thailand in 2004. Virology 413(2):226–230.  https://doi.org/10.1016/j.virol.2011.02.005 CrossRefPubMedGoogle Scholar
  18. 18.
    Palese P, Wang TT (2012) H5N1 influenza viruses: facts, not fear. Proc Natl Acad Sci U S A 109(7):2211–2213.  https://doi.org/10.1073/pnas.1121297109 CrossRefPubMedPubMedCentralGoogle Scholar
  19. 19.
    Enserink M (2011) Infectious diseases. Controversial studies give a deadly flu virus wings. Science 334(6060):1192–1193.  https://doi.org/10.1126/science.334.6060.1192 CrossRefPubMedGoogle Scholar
  20. 20.
    Fouchier RA, Garcia-Sastre A, Kawaoka Y, Barclay WS, Bouvier NM, Brown IH, Capua I, Chen H, Compans RW, Couch RB, Cox NJ, Doherty PC, Donis RO, Feldmann H, Guan Y, Katz J, Klenk HD, Kobinger G, Liu J, Liu X, Lowen A, Mettenleiter TC, Osterhaus AD, Palese P, Peiris JS, Perez DR, Richt JA, Schultz-Cherry S, Steel J, Subbarao K, Swayne DE, Takimoto T, Tashiro M, Taubenberger JK, Thomas PG, Tripp RA, Tumpey TM, Webby RJ, Webster RG (2012) Pause on avian flu transmission research. Science 335(6067):400–401.  https://doi.org/10.1126/science.335.6067.400 10.1126/science.1219412CrossRefPubMedGoogle Scholar
  21. 21.
    Fouchier RA, Garcia-Sastre A, Kawaoka Y (2012) Pause on avian flu transmission studies. Nature 481(7382):443.  https://doi.org/10.1038/481443a CrossRefPubMedGoogle Scholar
  22. 22.
    Fouchier RA, Garcia-Sastre A, Kawaoka Y (2013) H5N1 virus: transmission studies resume for avian flu. Nature 493(7434):609.  https://doi.org/10.1038/nature11858 CrossRefPubMedGoogle Scholar
  23. 23.
    Fouchier RA, Garcia-Sastre A, Kawaoka Y, Barclay WS, Bouvier NM, Brown IH, Capua I, Chen H, Compans RW, Couch RB, Cox NJ, Doherty PC, Donis RO, Feldmann H, Guan Y, Katz JM, Kiselev OI, Klenk HD, Kobinger G, Liu J, Liu X, Lowen A, Mettenleiter TC, Osterhaus AD, Palese P, Peiris JS, Perez DR, Richt JA, Schultz-Cherry S, Steel J, Subbarao K, Swayne DE, Takimoto T, Tashiro M, Taubenberger JK, Thomas PG, Tripp RA, Tumpey TM, Webby RJ, Webster RG (2013) Transmission studies resume for avian flu. Science 339(6119):520–521.  https://doi.org/10.1126/science.1235140 CrossRefPubMedGoogle Scholar
  24. 24.
    Fouchier R, Osterhaus AB, Steinbruner J, Yuen KY, Henderson DA, Klotz L, Sylvester E, Taubenberger JK, Ebright RH, Heymann DL (2012) Preventing pandemics: the fight over flu. Nature 481(7381):257–259.  https://doi.org/10.1038/481257a CrossRefPubMedGoogle Scholar
  25. 25.
    Klotz LC, Sylvester EJ (2012) The unacceptable risks of a man-made pandemic. Bulletin of the Atomic Scientists web edition: http://thebulletin.org/unacceptable-risks-man-made-pandemic
  26. 26.
    Lipsitch M, Plotkin JB, Simonsen L, Bloom B (2012) Evolution, safety, and highly pathogenic influenza viruses. Science 336(6088):1529–1531.  https://doi.org/10.1126/science.1223204 CrossRefPubMedPubMedCentralGoogle Scholar
  27. 27.
    Kaiser J (2014) U.S. halts two dozen risky virus studies. Science 346(6208):404.  https://doi.org/10.1126/science.346.6208.404 CrossRefPubMedGoogle Scholar
  28. 28.
    Council IoMaNR (2015) Potential risks and benefits of gain-of-function research: summary of a workshop. National Academies Press. http://dels.nas.edu/Workshop-Summary/Potential-Risks-Benefits-Gain/21666, Washington, DC.  https://doi.org/10.17226/21666 CrossRefGoogle Scholar
  29. 29.
    National Academies of Sciences E, and Medicine (2016) Gain-of-function research: summary of the second symposium, March 10–11, 2016. National Academies Press. https://www.nap.edu/catalog/23484/gain-of-function-research-summary-of-the-second-symposium-march, Washington, DC.  https://doi.org/10.17226/23484 CrossRefGoogle Scholar
  30. 30.
    Lipsitch M (2014) Can limited scientific value of potential pandemic pathogen experiments justify the risks? MBio 5(5):e02008.  https://doi.org/10.1128/mBio.02008-14 CrossRefPubMedPubMedCentralGoogle Scholar
  31. 31.
    Evans NG, Lipsitch M, Levinson M (2015) The ethics of biosafety considerations in gain-of-function research resulting in the creation of potential pandemic pathogens. J Med Ethics 41(11):901–908.  https://doi.org/10.1136/medethics-2014-102619 CrossRefPubMedPubMedCentralGoogle Scholar
  32. 32.
    Kimman TG, Smit E, Klein MR (2008) Evidence-based biosafety: a review of the principles and effectiveness of microbiological containment measures. Clin Microbiol Rev 21(3):403–425.  https://doi.org/10.1128/CMR.00014-08 CrossRefPubMedPubMedCentralGoogle Scholar
  33. 33.
    Harding A, Byers K (2006) Epidemiology of laboratory-associated infections. In: Fleming D, Hunt D (eds) Biological safety. ASM Press, Washington, DC, pp 53–77.  https://doi.org/10.1128/9781555815899.ch4 CrossRefGoogle Scholar
  34. 34.
    Lipsitch M, Inglesby TV (2014) Moratorium on research intended to create novel potential pandemic pathogens. MBio 5(6):e02366.  https://doi.org/10.1128/mBio.02366-14 CrossRefPubMedPubMedCentralGoogle Scholar
  35. 35.
    Centers for Disease Control and Prevention (2014) Report on the potential exposure to anthrax. http://www.cdc.gov/about/pdf/lab-safety/Final_Anthrax_Report.pdf
  36. 36.
    Grady D, McNeil DG (2014) Ebola sample is mishandled at C.D.C. Lab in latest error. New York Times, p A1. http://www.nytimes.com/2014/12/25/health/cdc-ebola-error-in-lab-may-have-exposed-technician-to-virus.html
  37. 37.
    CDC (2014) Report on the inadvertent cross-contamination and shipment of a laboratory specimen with influenza virus H5N1. http://www.cdc.gov/about/pdf/lab-safety/investigationcdch5n1contaminationeventaugust15pdf
  38. 38.
    Lipsitch M, Inglesby TV (2015) Reply to “studies on influenza virus transmission between ferrets: the public health risks revisited”. MBio 6(1):e00041.  https://doi.org/10.1128/mBio.00041-15 CrossRefPubMedPubMedCentralGoogle Scholar
  39. 39.
    Lipsitch M (2014) Lack of statistical support for claim of “minimal set of substitutions” and limitations of the Ferret Model for human transmissibility [online comment on linster et al. identification, characterization, and natural selection of mutations driving airborne transmission of A/H5N1 virus]. Cell 127:329–339 http://www.cell.com/cell/comments/S0092-8674(14)00281-5 Google Scholar
  40. 40.
    Lipsitch M, Barclay W, Raman R, Russell CJ, Belser JA, Cobey S, Kasson PM, Lloyd-Smith JO, Maurer-Stroh S, Riley S, Beauchemin CA, Bedford T, Friedrich TC, Handel A, Herfst S, Murcia PR, Roche B, Wilke CO, Russell CA (2016) Viral factors in influenza pandemic risk assessment. eLife 5:e18491.  https://doi.org/10.7554/eLife.18491 CrossRefPubMedPubMedCentralGoogle Scholar
  41. 41.
    Kryazhimskiy S, Dushoff J, Bazykin GA, Plotkin JB (2011) Prevalence of epistasis in the evolution of influenza A surface proteins. PLoS Genet 7(2):e1001301.  https://doi.org/10.1371/journal.pgen.1001301 CrossRefPubMedPubMedCentralGoogle Scholar
  42. 42.
    Tharakaraman K, Jayaraman A, Raman R, Viswanathan K, Stebbins NW, Johnson D, Shriver Z, Sasisekharan V, Sasisekharan R (2013) Glycan receptor binding of the influenza A virus H7N9 hemagglutinin. Cell 153(7):1486–1493.  https://doi.org/10.1016/j.cell.2013.05.034 CrossRefPubMedPubMedCentralGoogle Scholar
  43. 43.
    Tharakaraman K, Raman R, Viswanathan K, Stebbins NW, Jayaraman A, Krishnan A, Sasisekharan V, Sasisekharan R (2013) Structural determinants for naturally evolving H5N1 hemagglutinin to switch its receptor specificity. Cell 153(7):1475–1485.  https://doi.org/10.1016/j.cell.2013.05.035 CrossRefPubMedPubMedCentralGoogle Scholar
  44. 44.
    Buhnerkempe MG, Gostic K, Park M, Ahsan P, Belser JA, Lloyd-Smith JO (2015) Mapping influenza transmission in the ferret model to transmission in humans. eLife 4:e07969.  https://doi.org/10.7554/eLife.07969 CrossRefPubMedCentralGoogle Scholar
  45. 45.
    Russell CA, Kasson PM, Donis RO, Riley S, Dunbar J, Rambaut A, Asher J, Burke S, Davis CT, Garten RJ, Gnanakaran S, Hay SI, Herfst S, Lewis NS, Lloyd-Smith JO, Macken CA, Maurer-Stroh S, Neuhaus E, Parrish CR, Pepin KM, Shepard SS, Smith DL, Suarez DL, Trock SC, Widdowson MA, George DB, Lipsitch M, Bloom JD (2014) Improving pandemic influenza risk assessment. eLife 3:e03883.  https://doi.org/10.7554/eLife.03883 CrossRefPubMedPubMedCentralGoogle Scholar
  46. 46.
    Trock SC, Burke SA, Cox NJ (2012) Development of an influenza virologic risk assessment tool. Avian Dis 56(4 Suppl):1058–1061CrossRefPubMedGoogle Scholar
  47. 47.
    Moncorge O, Mura M, Barclay WS (2010) Evidence for avian and human host cell factors that affect the activity of influenza virus polymerase. J Virol 84(19):9978–9986.  https://doi.org/10.1128/JVI.01134-10 CrossRefPubMedPubMedCentralGoogle Scholar
  48. 48.
    Xiong X, Coombs PJ, Martin SR, Liu J, Xiao H, McCauley JW, Locher K, Walker PA, Collins PJ, Kawaoka Y, Skehel JJ, Gamblin SJ (2013) Receptor binding by a ferret-transmissible H5 avian influenza virus. Nature 497(7449):392–396.  https://doi.org/10.1038/nature12144 CrossRefPubMedGoogle Scholar
  49. 49.
    Stevens J, Blixt O, Glaser L, Taubenberger JK, Palese P, Paulson JC, Wilson IA (2006) Glycan microarray analysis of the hemagglutinins from modern and pandemic influenza viruses reveals different receptor specificities. J Mol Biol 355(5):1143–1155.  https://doi.org/10.1016/j.jmb.2005.11.002 CrossRefPubMedGoogle Scholar
  50. 50.
    Russier M, Yang G, Marinova-Petkova A, Vogel P, Kaplan BS, Webby RJ, Russell CJ (2017) H1N1 influenza viruses varying widely in hemagglutinin stability transmit efficiently from swine to swine and to ferrets. PLoS Pathog 13(3):e1006276.  https://doi.org/10.1371/journal.ppat.1006276 CrossRefPubMedPubMedCentralGoogle Scholar
  51. 51.
    Lakdawala SS, Jayaraman A, Halpin RA, Lamirande EW, Shih AR, Stockwell TB, Lin X, Simenauer A, Hanson CT, Vogel L, Paskel M, Minai M, Moore I, Orandle M, Das SR, Wentworth DE, Sasisekharan R, Subbarao K (2015) The soft palate is an important site of adaptation for transmissible influenza viruses. Nature 526:122.  https://doi.org/10.1038/nature15379 CrossRefPubMedPubMedCentralGoogle Scholar
  52. 52.
    Krenn BM, Egorov A, Romanovskaya-Romanko E, Wolschek M, Nakowitsch S, Ruthsatz T, Kiefmann B, Morokutti A, Humer J, Geiler J, Cinatl J, Michaelis M, Wressnigg N, Sturlan S, Ferko B, Batishchev OV, Indenbom AV, Zhu R, Kastner M, Hinterdorfer P, Kiselev O, Muster T, Romanova J (2011) Single HA2 mutation increases the infectivity and immunogenicity of a live attenuated H5N1 intranasal influenza vaccine candidate lacking NS1. PLoS One 6(4):e18577.  https://doi.org/10.1371/journal.pone.0018577 CrossRefPubMedPubMedCentralGoogle Scholar
  53. 53.
    Davis CT, Chen LM, Pappas C, Stevens J, Tumpey TM, Gubareva LV, Katz JM, Villanueva JM, Donis RO, Cox NJ (2014) Use of highly pathogenic avian influenza A(H5N1) gain-of-function studies for molecular-based surveillance and pandemic preparedness. MBio 5(6):e02431.  https://doi.org/10.1128/mBio.02431-14 CrossRefPubMedPubMedCentralGoogle Scholar
  54. 54.
    Lipsitch M (2016) Comment on “gain-of-function research and the relevance to clinical practice”. J Infect Dis 214(8):1284–1285.  https://doi.org/10.1093/infdis/jiw348 CrossRefPubMedGoogle Scholar
  55. 55.
    Jimenez-Alberto A, Alvarado-Facundo E, Ribas-Aparicio RM, Castelan-Vega JA (2013) Analysis of adaptation mutants in the hemagglutinin of the influenza A(H1N1)pdm09 virus. PLoS One 8(7):e70005.  https://doi.org/10.1371/journal.pone.0070005 CrossRefPubMedPubMedCentralGoogle Scholar
  56. 56.
    Larsson P, Kasson PM (2013) Lipid tail protrusion in simulations predicts fusogenic activity of influenza fusion peptide mutants and conformational models. PLoS Comput Biol 9(3):e1002950.  https://doi.org/10.1371/journal.pcbi.1002950 CrossRefPubMedPubMedCentralGoogle Scholar
  57. 57.
    Ripoll DR, Khavrutskii IV, Chaudhury S, Liu J, Kuschner RA, Wallqvist A, Reifman J (2012) Quantitative predictions of binding free energy changes in drug-resistant influenza neuraminidase. PLoS Comput Biol 8(8):e1002665.  https://doi.org/10.1371/journal.pcbi.1002665 CrossRefPubMedPubMedCentralGoogle Scholar
  58. 58.
    Shelton H, Roberts KL, Molesti E, Temperton N, Barclay WS (2013) Mutations in haemagglutinin that affect receptor binding and pH stability increase replication of a PR8 influenza virus with H5 HA in the upper respiratory tract of ferrets and may contribute to transmissibility. J Gen Virol 94(Pt 6):1220–1229.  https://doi.org/10.1099/vir.0.050526-0 CrossRefPubMedPubMedCentralGoogle Scholar
  59. 59.
    Shelton H, Ayora-Talavera G, Ren J, Loureiro S, Pickles RJ, Barclay WS, Jones IM (2011) Receptor binding profiles of avian influenza virus hemagglutinin subtypes on human cells as a predictor of pandemic potential. J Virol 85(4):1875–1880.  https://doi.org/10.1128/JVI.01822-10 CrossRefPubMedGoogle Scholar
  60. 60.
    Gong LI, Suchard MA, Bloom JD (2013) Stability-mediated epistasis constrains the evolution of an influenza protein. eLife 2:e00631.  https://doi.org/10.7554/eLife.00631 CrossRefPubMedPubMedCentralGoogle Scholar
  61. 61.
    Cauldwell AV, Moncorge O, Barclay WS (2013) Unstable polymerase-nucleoprotein interaction is not responsible for avian influenza virus polymerase restriction in human cells. J Virol 87(2):1278–1284.  https://doi.org/10.1128/JVI.02597-12 CrossRefPubMedPubMedCentralGoogle Scholar
  62. 62.
    Tamuri AU, Dos Reis M, Hay AJ, Goldstein RA (2009) Identifying changes in selective constraints: host shifts in influenza. PLoS Comput Biol 5(11):e1000564.  https://doi.org/10.1371/journal.pcbi.1000564 CrossRefPubMedPubMedCentralGoogle Scholar
  63. 63.
    dos Reis M, Tamuri AU, Hay AJ, Goldstein RA (2011) Charting the host adaptation of influenza viruses. Mol Biol Evol 28(6):1755–1767.  https://doi.org/10.1093/molbev/msq317 CrossRefPubMedGoogle Scholar
  64. 64.
    Jonges M, Meijer A, Fouchier RA, Koch G, Li J, Pan JC, Chen H, Shu YL, Koopmans MP (2013) Guiding outbreak management by the use of influenza A(H7Nx) virus sequence analysis. Euro Surveill 18(16):20460PubMedGoogle Scholar
  65. 65.
    Wong EH, Smith DK, Rabadan R, Peiris M, Poon LL (2010) Codon usage bias and the evolution of influenza A viruses. Codon usage biases of influenza virus. BMC Evol Biol 10:253.  https://doi.org/10.1186/1471-2148-10-253 CrossRefPubMedPubMedCentralGoogle Scholar
  66. 66.
    Zhang Q, Shi J, Deng G, Guo J, Zeng X, He X, Kong H, Gu C, Li X, Liu J, Wang G, Chen Y, Liu L, Liang L, Li Y, Fan J, Wang J, Li W, Guan L, Li Q, Yang H, Chen P, Jiang L, Guan Y, Xin X, Jiang Y, Tian G, Wang X, Qiao C, Li C, Bu Z, Chen H (2013) H7N9 influenza viruses are transmissible in ferrets by respiratory droplet. Science 341(6144):410–414.  https://doi.org/10.1126/science.1240532 CrossRefPubMedGoogle Scholar
  67. 67.
    Gustin KM, Katz JM, Tumpey TM, Maines TR (2013) Comparison of the levels of infectious virus in respirable aerosols exhaled by ferrets infected with influenza viruses exhibiting diverse transmissibility phenotypes. J Virol 87(14):7864–7873.  https://doi.org/10.1128/JVI.00719-13 CrossRefPubMedPubMedCentralGoogle Scholar
  68. 68.
    Chou YY, Albrecht RA, Pica N, Lowen AC, Richt JA, Garcia-Sastre A, Palese P, Hai R (2011) The M segment of the 2009 new pandemic H1N1 influenza virus is critical for its high transmission efficiency in the Guinea pig model. J Virol 85(21):11235–11241.  https://doi.org/10.1128/JVI.05794-11 CrossRefPubMedPubMedCentralGoogle Scholar
  69. 69.
    Yen HL, Liang CH, Wu CY, Forrest HL, Ferguson A, Choy KT, Jones J, Wong DD, Cheung PP, Hsu CH, Li OT, Yuen KM, Chan RW, Poon LL, Chan MC, Nicholls JM, Krauss S, Wong CH, Guan Y, Webster RG, Webby RJ, Peiris M (2011) Hemagglutinin-neuraminidase balance confers respiratory-droplet transmissibility of the pandemic H1N1 influenza virus in ferrets. Proc Natl Acad Sci U S A 108(34):14264–14269.  https://doi.org/10.1073/pnas.1111000108 CrossRefPubMedPubMedCentralGoogle Scholar
  70. 70.
    Krammer F, Palese P (2013) Influenza virus hemagglutinin stalk-based antibodies and vaccines. Curr Opin Virol 3(5):521–530.  https://doi.org/10.1016/j.coviro.2013.07.007 CrossRefPubMedPubMedCentralGoogle Scholar
  71. 71.
    Wei CJ, Yassine HM, McTamney PM, Gall JG, Whittle JR, Boyington JC, Nabel GJ (2012) Elicitation of broadly neutralizing influenza antibodies in animals with previous influenza exposure. Sci Transl Med 4(147):147ra114.  https://doi.org/10.1126/scitranslmed.3004273 CrossRefPubMedGoogle Scholar
  72. 72.
    Schmitz N, Beerli RR, Bauer M, Jegerlehner A, Dietmeier K, Maudrich M, Pumpens P, Saudan P, Bachmann MF (2012) Universal vaccine against influenza virus: linking TLR signaling to anti-viral protection. Eur J Immunol 42(4):863–869.  https://doi.org/10.1002/eji.201041225 CrossRefPubMedGoogle Scholar
  73. 73.
    Hughes B, Hayden F, Perikov Y, Hombach J, Tam JS (2012) Report of the 5th meeting on influenza vaccines that induce broad spectrum and long-lasting immune responses, World Health Organization, Geneva, 16–17 November 2011. Vaccine 30(47):6612–6622.  https://doi.org/10.1016/j.vaccine.2012.08.073 CrossRefPubMedGoogle Scholar
  74. 74.
    Doyle TM, Jaentschke B, Van Domselaar G, Hashem AM, Farnsworth A, Forbes NE, Li C, Wang J, He R, Brown EG, Li X (2013) The universal epitope of influenza A viral neuraminidase fundamentally contributes to enzyme activity and viral replication. J Biol Chem 288(25):18283–18289.  https://doi.org/10.1074/jbc.M113.468884 CrossRefPubMedPubMedCentralGoogle Scholar
  75. 75.
    Everitt AR, Clare S, Pertel T, John SP, Wash RS, Smith SE, Chin CR, Feeley EM, Sims JS, Adams DJ, Wise HM, Kane L, Goulding D, Digard P, Anttila V, Baillie JK, Walsh TS, Hume DA, Palotie A, Xue Y, Colonna V, Tyler-Smith C, Dunning J, Gordon SB, Smyth RL, Openshaw PJ, Dougan G, Brass AL, Kellam P (2012) IFITM3 restricts the morbidity and mortality associated with influenza. Nature 484(7395):519–523.  https://doi.org/10.1038/nature10921 CrossRefPubMedPubMedCentralGoogle Scholar
  76. 76.
    Dormitzer PR, Suphaphiphat P, Gibson DG, Wentworth DE, Stockwell TB, Algire MA, Alperovich N, Barro M, Brown DM, Craig S, Dattilo BM, Denisova EA, De Souza I, Eickmann M, Dugan VG, Ferrari A, Gomila RC, Han L, Judge C, Mane S, Matrosovich M, Merryman C, Palladino G, Palmer GA, Spencer T, Strecker T, Trusheim H, Uhlendorff J, Wen Y, Yee AC, Zaveri J, Zhou B, Becker S, Donabedian A, Mason PW, Glass JI, Rappuoli R, Venter JC (2013) Synthetic generation of influenza vaccine viruses for rapid response to pandemics. Sci Transl Med 5(185):185ra168.  https://doi.org/10.1126/scitranslmed.3006368 CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Departments of Epidemiology and Immunology and Infectious Diseases, Center for Communicable Disease DynamicsHarvard TH Chan School of Public HealthBostonUSA

Personalised recommendations