García-García J, Ramos C

Language: Spanish
References: 175
Page: 244-267
PDF size: 422.98 Kb.

ABSTRACT

Seasonal influenza is an acute and recurring respiratory disease known since ancient times, occuring, in particular, during winter months and having an elevated effect on public health worldwide. The disease has high morbidity rates for people of all ages and particularly high mortality rates for children, adults over 60 years old, patients with chronic illnesses and pregnant women. Prevention control strategies include vaccination using inactivated, subunit or genetically modified virus vaccines. Influenza in humans is caused by two subtypes of influenza virus A and one of influenza virus B. The influenza virus A that affects humans mutates easily, thereby often causing new antigenic variants of each subtype to emerge, requiring the inclusion of such variants in annual vaccines in order to assure proper immunization of the population. The influenza pandemic refers to the introduction and later worldwide spread of a new influenza virus in the human population, which occurs sporadically. Due to the lack of immunity in humans against the new virus, serious epidemics can be provoked resulting in high morbidity and mortality rates. Historically, influenza pandemics are a result of the transmission of the virus from birds to humans, or the transfer of such genes to seasonal influenza. Wild waterfowl –both migratory and shore birds– carry a large diversity of influenza virus subtypes, which are eventually transmitted to domestic birds. Some of those viruses cross the species barrier and infect mammals, including humans. The adaptation process of the avian virus to mammal hosts requires time. Therefore, the presentation of these cases can take several years. Since December 2003, in several Southeast Asian countries a large proportion of domestic birds have been affected by an avian influenza epidemic (subtype H5N1). By Februrary 2006, the epidemic had already affected countries in Europe and Africa, having a significant economic impact on commercial poultry due to the more than 180 million birds that were sacrificed. Some strains of this avian influenza virus have directly, although incipiently, infected the human population. The virus has not yet acquired with complete efficiency person-to-person infection and transmission, which has limited its spread among humans. Since the mortality rate in infected individuals is greater than 50%, the World Health Organization (WHO) called on their member countries to establish preparation and emergency plans against the threat of a possible pandemic associated with H5N1 virus, or another virus related to common influenza. These actions are intended to prevent or reduce the impact of the threat, as experienced in previous pandemics, such as in 1918 when roughly 40 million people died worldwide. The prevention and control plans include, among other strategies, vaccination and antiviral medications. Nevertheless, to date there are no vaccines to be administered to the population in the case of a new influenza pandemic emergency and it is possible that countries that produce the annual seasonal influenza vaccine lack the capacity to produce the pandemic virus vaccine in a short period of time. In addition, recent studies have identified the existence of influenza virus strains resistant to common antiviral agents. The purpose of this review is to update the basic concepts of influenza in order to strengthen epidemiological surveillance of the disease and reinitiate prevention and control actions in the event of a pandemic.

REFERENCES

1. Hilleman MR. Realities and enigmas of human viral influenza: pathogenesis, epidemiology and control. Vaccine 2002;20:3068-3087.

2. Cox NJ, Subbarao K. Influenza. Lancet 1999;354:1277-1282.

3. Simonsen L. The global impact of influenza on morbidity and mortality. Vaccine 1999;17:S3-S10.

4. Webster RG, Bean WJ, Goren OT, Chambers TM, Kawaoka Y. Evolution and ecology of influenza A viruses. Microbiol Rev 1992;56:53-179.

5. Webby RJ, Webster RG. Emergence of influenza A viruses. Phil Trans R Soc Lond B 2001;356:1817-1828.

6. Webster RG, Laver WG, Air GM. Antigenic variation among influenza type A influenza viruses. En: Palese P, Kingsbury DW, ed.: Genetics of influenza viruses. New York: Springer, 1983:127-168

7. Hampson AW, Cox NJ. Global surveillance for pandemic influenza: are we prepared. En: Brown LE, Hampson AW, Webster RD, ed.: Options for the control of influenza. Amsterdam: Elsevier, 1996:50-59.

8. Hoy AJ, Gregory V, Douglas AR, Lin YP. The evolution of human influenza viruses. Philos Trans R Soc Lond B 2001;356:1861-1870.

9. Claas EC, Osterhaus ADME, van Beek R, DeJong JC, Rimelzwaan GF, Senne DA et al. Human influenza A H5N1 virus related to a highly pathogenic avian influenza virus. Lancet 1996;351:472-477.

10. Cox NJ, Subbarao K. Global epidemiology of influenza: past and present. Annu Rev Med 2000;51:407-421.

11. Webster RG. Spanish influenza: the secrets remain. Proc Natl Acad Sci USA 1999;96:1164-1166.

12. Kolata G. Flu: the story of the great influenza pandemic of 1918 and the search for the virus that caused it. New York: Farrar, Straus and Giroux, 1999:330.

13. Murphy BR, Webster RG. Orthomyxoviruses. En: Knipe DM, Howley PM, ed. Fields virology vol. 1. 3a. ed. Philadelphia: Lippincott-Raven, 1996:1397-1445.

14. Viesca TC. Medicina prehispánica de México. México, Panorama Editorial,1996;49-50.

15. Valdez AR. Pandemia de gripe. Sinaloa, 1918-1919. Elementos 2002;47:37-43.

16. Hinshaw VS, Webster RG. The natural history of influenza A viruses. En: AS Beare ed.: Basic and applied influenza research. Boca Raton, Fla: CRC Press, Inc, 1982;79-104.

17. Hilleman MR. Asian influenza: initial identification of Asiatic virus and antibody response in volunteers to vaccination. En: US Department of Health, Education and Welfare. Proceedings of the Special Conference on Influenza. Washington, DC: USDHEW, 1957;17-24.

18. Lindstrom SE, Cox NJ, Klimov A. Genetic analysis of human H2N2 and early H3N2 influenza viruses, 1957–1972: Evidence for genetic divergence and multiple reassortment events. Virology 2004;328:101-119.

19. Yuen KY, Chan PK, Peiris M, Tsang DN, Que TL, Shortridge KF et al. Clinical features and rapid viral diagnosis of human disease associated with avian influenza A H5N1 virus. Lancet 1998;351:467-471.

20. Claas EC, Osterhaus AD, Van Beek R, De Jong JC, Rimmelzwaan GF, Senne DA et al. Human influenza A H5N1 virus related to a highly pathogenic avian influenza virus. Lancet 1998;351:472-477.

21. Li KS, Guan Y, Wang J, Smith GJ Xu KM et al. Genesis of a highly pathogenic and potentially pandemic H5Nl influenza virus in eastern Asia. Nature 2004;430:209-213.

22. Shortridge KF, Peiris JSM, Guan Y. The next influenza pandemic: lessons from Hong Kong. J Appl Microbiol 2003;94;70S-79S.

23. Peiris M, Yuen KY, Leung CW, Chan KH, Ip PL, Lai RWM et al. Human infection with influenza H9N2. Lancet 1999;354:916-917.

24. Kemink SA, Fouchier RA, Rozendaal FW, Broekman JM, Koopmans M, Osterhaus AD et al. A fatal infection due to avian influenza-A (H7N7) virus and adjustment of the preventive measures. Ned Tijdschr Geneeskd 2004;148:2190-2194.

25. Stegeman A, Bouma A, Elbers AR, de Jong MC, Nodelijk G, de Klerk F et al. Avian influenza A virus (H7N7) epidemic in The Netherlands in 2003: course of the epidemic and effectiveness of control measures. J Infect Dis 2004;190:2088-2095.

26. Tweed SA, Danuta MS, Samara TD, Andrew L, Petric M, Wayne L et al. Human illness from avian influenza H7N3, British Columbia S. Emerg Infect Dis 2004;10:2196-2199.

27. Hirst M, Astell CR, Griffith M, Coughlin SM, Moksa M, Zeng T et al. Novel avian influenza H7N3 strain outbreak, British Columbia. Emerg Infect Dis 2004;10:2192-2195.

28. Campitelli L, Mogavero E, De Marco MA, Delogu M, Puzelli S et al. Interspecies transmission of an H7N3 influenza virus from wild birds to intensively reared domestic poultry in Italy. Virology 2004;323:24-36.

29. Puzelli S, Di Trani L, Fabiani C, Campitelli L, De Marco MAl, Capua I et al. Serological analysis of serum samples from humans exposed to avian H7 influenza viruses in Italy between 1999 and 2003. J Infect Dis 2005;192:1318-1322.

30. Ministry of Health, Labour and Welfare of Japan disponible en:http://www.mhlw.go.jp/houdou/2006/01/h0110-4.html

31. Wright PF, Webster RG. Orthomyxoviruses. En: Knipe DM, Howley PM, ed Fields virology. vol. 1. 4a. ed. Philadelphia: Lippincott Williams and Wilkins, 2001:1533-1579.

32. Lamb RA. Genes and proteins of the influenza viruses. En: Krug RM, Fraenkel-Conrat H, Wagner RR, ed. The influenza viruses. New York, Plenum Press, 1989:1-88.

33. Smith W, Andrewes CH, Laidlaw PP. A virus obtained from influenza patients. Lancet 1933;2:66-68.

34. Francis Jr T. A new type of virus from epidemic influenza. Science 1940;92:405-408.

35. Osterhaus AD, Rimmelzwaan GF, Martina BE, Bestebroer TM, Fouchier RA. Influenza B virus in seals. Science 2000;288:1051-1053.

36. Francis Jr T, Quilligan Jr JJ, Minuse E. Identification of another epidemic respiratory disease. Science 1950;112:495-497.

37. Kimura H, Abico C, Peng G, Muraki Y, Sugawara K, Hong S et al. Interspecies transmission of influenza C virus between humans and pigs. Virus Res 1997;48:71-79.

38. Yamaoka M, Hotta H, Itoh M, Homma M. Prevalence of antibody to influenza C virus among pigs in Hyogo Prefecture, Japan. J Gen Virol 1991;72:711-714.

39. Ohwada K, Kitame F, Sugawara K, Nishimura H, Homma M, Nakamura K. Distribution of antibody to influenza C virus in dogs and pigs in Yamagata prefecture, Japan. Microbiol Immunol 1978;31:1173-1180.

40. WHO Memorandum. A revised system of nomenclature for influenza viruses. Bull WHO 1980;58:585-591.

41. Guan Y, Peiris JS, Lipatov AS, Ellis TM, Dyrting KC et al. Emergence of multiple genotypes of H5N1 avian influenza viruses in Hong Kong SAR. Proc Natl Acad Sci USA 2002;99:8950-8955.

42. Webster RG, Peiris M, Chen H, Guan Y. H5N1 outbreaks and enzootic influenza. Emerg Infect Dis 2006;12:3-8.

43. Spackman E, Senne DA, Davison S, Suarez DL. Sequence analysis of recent H7 avian influenza viruses associated with three different outbreaks in commercial poultry in the United States. J Virol 2003;77:13399-13402.

44. Dennis JA. A review of avian influenza in different bird species. Vet Microbiol 2000;74:3-13.

45. Taubenberger JK, Morens DM. 1918 influenza: the mother of all pandemics. Emerg Infect Dis 2006;12:15-22.

46. Kawaoka Y, Yamnikova S, Chambers TM, Lvov DK, Webster RG. Molecular characterization of a new hemaglutinin subtype H14 of influenza virus A. Virology 1990;179:759-767.

47. Röhm C, Zhou N, Suss J, Mackenzie J, Webster RG. Characterization of a novel influenza hemagglutinin, H15. Criteria for determination of influenza subtypes. Virology 1996;217:508-516.

48. Fouchier RA, Munster V, Wallensten A, Bestebroer TM, Herfst S, Smith DR et al. Characterization of a novel influenza A virus hemagglutinin subtype (H16) obtained from black-headed gulls. J Virol 2005;79:2814-2822 .

49. Suarez DL. Evolution of avian influenza viruses. Vet Microbiol 2000;74:15-27.

50. Kennedy FS, Gao P, Guan Y, Ito T, Kawaoka Y, Markwell D et al. Interspecies transmission of influenza viruses: H5N1 virus and Hong Kong SAR perspective. Vet Microbiol 2000;74:141-147.

51. Geraci JR, St Aubin DJ, Barker IK, Webster RG, Hinshaw VS, Bean WJ et al. Mass mortality of harbor seals: pneumonia associated with influenza A virus. Science. 1982;215:1129-1131.

52. Hinshaw VS, Bean WJ, Geraci JR, Fiorelli P Early G et al. Characterization of two influenza A viruses from a pilot whale. J Virol 1986;58:655-656.

53. Gaydos JC, Hodder RA, Top FH. Swine influenza A at Fort Dix, New Jersey (January-February 1976). IIl transmission and morbidity in units with cases. J Infect Dis 1977;136:363-368.

54. Sovinova O, Tumova B, Pouska F, Nemec J. Isolation of a virus causing respiratory disease in horses. Acta Virol 1958;2:52-61.

55. Keawcharoen J, Oraveerakul K, Kuiken T, Fouchier RAM, Amonsin A, Payungporn S et al. Avian influenza H5N1 in tigers and leopards. Emerg Infect Dis 2004;10:2189-2191.

56. Crawford PC, Dubovi EJ, Castlemen WL, Stephenson I, Gibbs EP, Chen L et al. Transmission of equine influenza virus to dogs. Science 2005;310:482-485.

57. Olsen CW, Brammer L, Easterday BC, Arden N, Belay E, Baker I et al. Serological evidence of H1 swine influenza virus infection in swine farm residents and employees. Emerg Infect Dis 2002;8:814-819.

58. Brown IH. The epidemiology and evolution of influenza viruses in pigs. Vet Microbiol 2000;74:29-46.

59. Chen W, Calvo PA, Malide D, Gibbs J, Shubert U, Bacik I et al. A novel influenza A virus mitochondrial protein that induces cell death. Nat Med 2001;7:1306-1312.

60. Colman PM. Neuraminidase; enzyme and antigen. En: Krugh RM, ed. The influenza viruses. New York: Penum Press, 1989:175-218.

61. Zebedee FL, dhi RA, Influenza A virus M2 protein: monoclonal antibody restriction of virus growth and detection of M2 in virions. J Virol 1988;62:2762-2772.

62. Horimoto T, Kawaoka Y. Influenza lessons from past pandemics, warnings from current incidents. Nat Rev Microbiol 2005;3:591-600.

63. Webster RG. Antigenic variation in influenza viruses. En: Domingo E, Webster R, Holland J, ed. Origin and evolution of viruses. San Diego, CA: Academic Press, 1999:377-390.

64. Webster RG, Hulse DJ. Microbial adaptation and change: avian influenza. Rev Sci Tech 2004;23:453-465.

65. Alexander DJ. A review of avian influenza in different bird species. Vet Microbiol 2000;74:3-13.

66. Webster RG. Influenza viruses. En: Webster RG, Granoff A, ed. Encyclopedia of virology. New York: Academic Press, 1994;2:709-715.

67. Holland J, Spindler K, Horodyski F, Grabau E, Nichol E, VandePol S. Rapid evolution of RNA genomes. Science 1982;215:1577-1585.

68. 68 Webby RJ, Webster RG. Emergence of influenza A viruses. Philos Trans R Soc Lond B Biol Sci 2001;356:1816-1828.

69. Kawaoka J, Krauss YS, Webster RG. Avian-to-human transmission of the PB1 gene of influenza A viruses in the 1957 and 1968 pandemics. J Virol 1989;63:4603-4608.

70. Weis W, Brown JH, Cusack S, Paulson JC, Skehel JJ, Wiley DC. Structure of the influenza virus haemagglutinin complexed with its receptor, sialic acid. Nature 1988;333:426-431.

71. Rogers GN, Paulson JC. Receptor binding properties of human and animal H1 influenza virus isolates. Virology 1989;173:317-322.

72. Ha Y, Stevens DJ, Skehel JJ, Wiley DC. X-ray structures of H5 and H9 swine influenza virus hemagglutinins bound to avian and human receptor analogs. Proc Nat Acad Sci USA 2001;98:11181-11186.

73. Rogers GN, Pritchet TJ, Lane JL, Paulson JC. Differential sensitivity of human, avian and equine influenza A viruses to a glycoprotein inhibitor of infection: selection of receptor specific variants. Virology 1983;131:394-408.

74. Castrucci MR, Donatelli I, Sidoli L, Barigazzi, Kawaoka Y, Webster RG. Genetic reassortment between avian and human influenza A viruses in Italian pigs. Virology 1993;193:503-506.

75. Connor RJ, Kawaoka Y, Webster RG, Paulson J. Receptor specificity in human, avian and equine H2 and H3 influenza viruses isolates. Virology 1994;205:17-23.

76. Sizuki Y. Sialobiology of influenza molecular mechanisms of host range variation of influenza viruses. Biol Pharm Bull 2005;28:399-408.

77. Ito T, Kawaoka Y. Host range barrier of influenza A viruses. Vet Microbiol 2000;74:71-75.

78. Conn CA, McClellan Jl, Maasab HF, Smitka CW, Majde JA, Kluger MJ. Cytokines and the acute phase response to influenza virus in mice. Am J Physiol 1995;268:78-84.

79. Bielefeldt-Ohmann H. Role of cytokines in the pathogenesis and treatment of respiratory diseases. En: Myers MJ, Murtaugh MP, ed. Cytokines in animal health and disease. New York: Marcel Dekker, 1995:291-332.

80. Falcon AM, Fernandez-Sesma, Nakaya Y, Moran TM, Ortiz J et al. Attenuation and immunogenicity in mice of temperature-sensitivity influenza viruses expressing truncated NS1 proteins. J Gen Virol 2005;86:2817-2821.

81. Taylor HP, Dimmock NJ. Mechanism of neutralization of influenza virus by secretory IgA is different from that of monomeric IgA or IgG. J Exp Med 1985;161:198-209.

82. Suarez DL, Schultz-Cherry S. Immunology of avian influenza virus: a review. Dev Comp Immunol 2000;24:269-283.

83. Karson DT. Cytotoxic T cells in influenza immunity. Semin Virol 1996;6:906-908.

84. Alexander DJ. Highly pathogenic avian influenza. En: OIE. Manual of standars for diagnostic tests and vaccines. 4a. edición. París: OIE, 2004:212-220

85. Perroncito E. Epizoozia tifoide nei gallinnacei. Annali Accademia Agriculture Torino 1878;21:87-126.

86. Capua I, Alexander DJ. Avian influenza: recent developments. Avian Pathol 2004;33:392-404.

87. Kawaoka Y, Webster RG. Sequence requirements for cleavage activation of influenza virus hemagglutinin expressed in mammalian cells. Proc Natl Acad Sci USA 1988;85:324-328.

88. Perdue ML, Suarez DL. Structural features of avian influenza virus hemagglutinin that influence virulence. Vet Microbiol 2000;74:77-86.

89. Bean WJ, Kawaoka Y, Wood JM, Pearson JE, Webster RG. Characterization of virulent and avirulent A/chiken/Pennsylvania/83 influenza A viruses: potential role of defective interfering RNAs in nature. J Virol 1985;54:151-160.

90. Guan Y, Poon LLM, Cheung CY, Ellis TM, Lim W et al. H5N1 influenza: a protean pandemic threat. Proc Natl Acad Sci USA 2004;101:8156-8161.

91. Crosby AW. America´s forgotten pandemic: the influenza of 1918. Cambridge: Cambridge University Press, 1989:329.

92. Taubenberger JK, Reid AH, Janczewsky TA, Fanning TG. Integrating historical clinical and molecular genetic data in order to explain the origin and virulence of the 1918 Spanish influenza virus. Phil Trans R Soc London B Biol Sci 2001;356:1829-1839.

93. Belshe RB. Origins of pandemic influenza lessons from 1918 virus. N Engl J Med 2005;353:2209-2211.

94. Scholtissek C, Rohde W, von Hoyningen V, Rott R. On the origin of the human influenza virus subtype H2N2 and H3N2. Virology 1978;87:13-20.

95. Kawaoka Y, Krauss S, Webster RG. Avian-to-human transmission of the PB1 gene of influenza A viruses in the 1957 and 1968 pandemics. J Virol 1989;63:4603-4608.

96. 96 Hileman MR. Personal historical chronicle of six decades of basic and applied research in virology, immunology, and vaccinology. Immunol Rev 1999;170:7-27.

97. Nakajima K, Desselberger U, Palese P. Recent human influenza A viruses are closely related genetically to strains isolated in 1950. Nature 1978;274:334-339.

98. World Health Organization. Wkly. Epidemiol Rec 2003;9:57-64.

99. Lu B, Zhou H, Ye D, Kemble G, Jin H. Improvement of influenza A/Fujian/411/02 (H3N2) virus growth in embryonated chicken eggs by balancing the hemagglutinin and neuroaminidase activities, using reverse genetics. J Virol 2005;79: 6763-6771.

100. Holmes EC, Ghedin E, Lipman DJ, Taubenberger JK. Whole-genome analysis of human influenza A virus reveals multiple persistent lineages and reassortment among recent H3N2 viruses. PLoS Biology 2005;3:1579-1589.

101. Jin H, Zhou H, Liu H, Chan W, Adhikary L et al. Two residues in the hemagglutinin of A/Fujian/411/02-like influenza viruses are responsible for antigenic drift from A/Panama/2007/99. Virology 2005;336:113-119.

102. Rao BL, Kadam SS. Isolation of recent variant influenza types A (H3N2) & B strains in Pune, India, during 1998. Indian J Med Res 2000;111:3-5.

103. Lindstrom SE, Cox NJ, Klimov A. Genetic analysis of human H2N2 and early H3N2 influenza viruses, 1957-1972: evidence for genetic divergence and multiple reassortment events. Virology 2004; 328:101-109.

104. CDC. Isolation of avian influenza A (H5N1) viruses from humans; Hong Kong, May-December 1997. MMWR 1997;46:1204-1207.

105. Subbarao K, Klimov A, Katz J, Regnery H, Lim W et al. Characterization of an avian influenza A (H5N1) virus isolated from a child with fatal respiratory illness. Science 1998;279:393-396.

106. Claas EC, Osterhaus AD, Van Beek R, De Jong JC; Rimeelzwaan GF, et al. Human influenza A H5N1 virus related to highly pathogenic avian influenza virus. Lancet 1998;351:472-477.

107. Suarez DL, Perdue ML, Cox N, Rowe T, Bender C et al. Comparisons of highly virulent H5N1 influenza A viruses isolated from humans and chickens from Hong Kong. J Virol 1998;72:6678-6688.

108. Shortridge KF, Zhpu NN, Guan Y, Gao P, Ito T et al. Characterization of avian H5N1 influenza viruses from poultry in Hong Kong. Virology 1998;252:331-342.

109. Webster RG. Influenza: An emerging disease. Emerg Infect Dis 1998;4:436-441.

110. Martin V, Sims L, Lubroth J, Pfeiffer D, Slingenbergh J et al. Epidemiology and ecology of highly pathogenic avian influenza with particular emphasis on South East Asia. Dev Biol 2006:124:23-36.

111. Webster RG, Guan Y, Poon L, Krauss S, Webby R et al. The spread of H5N1 bird flu epidemic in Asia in 2004. Arch Virol 2005;19:117-129.

112. World Organization for Animal Health (OIE). Highly pathogenic avian influenza in the Republic of Korea. Suspected outbreak. Disease information 2003;16: 270. Disponible en: ftp://ftp.oie.int/infos_san_archives/eng/2003/en_031212v16n50.pdf

113. World Organization for Animal Health (OIE). Update on avian influenza in animals (type H5). Disponible en: http://www.oie.int/downld/AVIAN%20INFLUENZA/A_AI-Asia.htm

114. World Health Organization Epidemia and pandemic alert and response (EPR) Avian Influenza. Disponible en: http://www.who.int/csr/disease/avian_influenza/en/index.html

115. Mase M, Tsukamoto K, Imada T, Imai K, Tanimura N et al. Characterization of H5N1 influenza A viruses isolated during the 2003-2004 influenza outbreaks in Japan. Virology 2005;5:167-176.

116. Desvaux S, Sorn S, Holl D, Chavernac D. Goutard F et al. HPAI surveillance programme in Cambodia: results and perspectives. Dev Biol 2006;124:211-224.

117. Mase M, Kim JH, Lee YJ, Tsukamoto K, Imada T et al. Genetic comparison of H5N1 influenza A viruses isolated from chickens in Japan and Korea. Microbiol Immunol 2005;49:871-874.

118. Alexander DJ. Avian influenza viruses and human health. Desv Biol 2006;124:77-84.

119. Snacken R, Kendal AP, Haaheim LR, Wood JM. The next influenza pandemic: lessons from Hong Kong, 1997. Emerg Infect Dis 1999;5:195-203.

120. World Health Organization Global Influenza Program Surveillance Network. Evolution of H5N1 avian influenza viruses in Asia. Emerg Infect Dis 2005;11:1515-1521.

121. Thorson A, Petzold M, Nguyen TK, Ekdahl K. Is exposure to sick or dead poultry associated with flulike illness?: a population-based study from rural area in Vietnam with outbreaks of highly pathogenic avian influenza. Arch Intern Med 2006;166:119-123.

122. Hien TT, Liem NT, Dung NT, San LT, Mai PP et al. Avian influenza A (H5N) in 10 patients in Vietnam. New Engl J Med 2004;350:1179-1188.

123. Morris RS, Jackson R. Epidemiology of H5N1 avian influenza in Asia and implications for region control. FAO report 2004.

124. Koopmaus M, Fouchier R, Wilbrink B, Meijer A, Natrop G, et al. Update of human infections with highly pathogenic avian influenza virus A/H7N7 during an outbreak in poultry in The Netherlands. Euro Surveill 2003;7:1-5.

125. Werner O, Starick E, Ground CH. Isolation and characterization of low pathogenic H7N7 influenza virus from a turkey in a small mixed free-range poultry flock in Germany. En: Proceedings of the fifth international Symposium on Avian Influenza, Athens, april 14-17. Avian Dis 2002;47:1104-1106.

126. Bowes VA. An overview of the 2004 outbreak of highly pathogenic avian influenza in British Columbia. En: Proceedings of the fifty-fourth Western Poultry Disease Conference. Vancouver, Canada: 25-27 2005;10-13.

127. García GJ, Méndez OM. “Estudios sobre algunas características de los virus de influenza Aviar de baja patogenicidad aislados en México, de enero a septiembre de 1994. En: Memorias de la XXI Convención Anual ANECA y 45th Western Poultry Disease Conference. Mayo 1995 Cancún, Q. Roo. 1995;295-296.

128. García-García J, Medina PA. La influenza aviar en México. En: Memorias del Simposio Internacional de Influenza Aviar. Sociedad Venezolana de Veterinarios Especialistas en Aves. Maracay, Venezuela: 4 y 5 noviembre 1999;32-42.

129. García-García J, Medina PA. Influenza aviar. En: Memorias del Simposio Internacional de influenza aviar. Sociedad Venezolana de Veterinarios Especialistas en Aves. Maracay, Venezuela: 4 y 5 noviembre 1999;1-11.

130. Villareal CL, Flores AO. The Mexican avian influenza (H5N2) outbreak. En: Proceedings of the Fourth International Symposium on Avian Influenza. Atenas: 14-17 de abril 1997;18-22.

131. García-García J. Avian influenza update from American countries. En: Procedings of IDEXX Poultry Show Conference. Atlanta, GA: 25 de enero 2006;1-10.

132. Garcia M, Crawford JM, Latimer JW, Rivera-Cruz E, Perdue ML. Heterogenecity in the hemagglutinin gene and emergence of highly pathogenic phenotype among recent H5N2 avian influenza viruses from Mexico. J Gen Virol 1996;77: 1493-1504.

133. Horimoto T, Rivera E, Pearson J, Senne D, Krauss S et al. Origin and molecular changes associated with emergence of highly pathogenic H5N2 influenza virus in Mexico. Virology 1995; 213: 223-230.

134. Swyne DE, Suarez DL. Avian influenza in Europe, Asia and Central America during 2001. En: Proceedings of the 104th Annual Meeting of the US Animal Health Association. Richmond, VA: noviembre 2001;465-470.

135. Capua I, Alexander DJ. Avian influenza: recent developments. Avian Path 2004;33:393-404.

136. Lee CW, Denne DA, Suarez DL. Effect of vaccine use in the evolution of Mexican lineage H5N2 avian influenza virus. J Virol 2004;78:8372-8381.

137. García-García J, Rodríguez VH, Hernández MA, Cerón HM. Vacunas contra influenza aviar. En: Curso de Bioseguridad para el Control y Prevención de la Influenza Aviar. México, D.F.: AN4ECA, 20 de octubre 1995;27-35.

138. Hirst GK. Comparison of influenza virus strains from three epidemics. J Exp Med 1947;86:367-381.

139. Francis Jr T. Vaccination against influenza. Bull Who 1953;8:725-741.

140. World Health Organization. Influenza vaccines. Wkly Epidemiol Rec 2002;77:230-239.

141. World Health Organization. WHO global influenza programme: survey on capacities of national influenza centres, January-June 2002. Wkly Epidemiol Rec 2002;77:350-356.

142. World Health Organization. Vaccines for pandemic influenza. Informal meeting of WHO, influenza vaccine manufacturers, national licensing agencies, and government representatives on influenza pandemic vaccines. Summary report. Ginebra Suiza: noviembre 2004. Disponible en: http://www.who.int/csr/disease/influenza/vaccinerecommendations1/en/

143. World Health Organization. Influenza vaccines. Wkly Epidemiol Rec 2002;75:281-288.

144. Liebert MA. Profile, interview with David S. Fedson MD. Biosecur Bioterror 2005;3:9-15.

145. Barry DW, Mayner RE, Staton E, Dunlap R, Rastogy JE et al. Comparative trial of influenza vaccines in man. Am J Epidem 1976;104:34-46.

146. Kendal AP. Cold-adapted live attenuated influenza vaccines developed in Russia: Can they contribute to meeting the needs for influenza control in other countries. Eur J Epidemiol 1997;13:591-609.

147. Edwards KM, Dupont WD, Westrich MK, Plummer Jr WD, Palmer PS. A randomized controlled trial of cold-adapted and inactivated vaccines for prevention of influenza A disease. J Infect Dis 1994;169:68-76.

148. Mendelmen PM, Cordova J, Cho I. Safety and effectiveness of influenza virus vaccine, trivalent, types A and B, types A and B, live, cold-adapted (CAIV-T) in healthy children and healthy adults. Vaccine 2001;19:2221-2226.

149. Pfleiderer M, Löwer J, Kurth R. Cold-attenuated live influenza vaccine, a risk-benefit assessment. Vaccine 2002;20:886-894.

150. Youngner JS, Treanor JJ, Betts RF, Whitaker-Dowling P. Effect of simultaneous administration of cold-adapted and wild-type influenza infection in humans. J Clin Microbiol 1994;32:750-754.

151. Webster RG, Robinson HL. DNA vaccines: a review of developments. Biol Drugs 1997;8:273-292.

152. Donnelly JJ, Ulmer JB, Shiver JW, Liu MA. DNA vaccines. Annu Rev Immunol 1997;15:617-648.

153. Ulmer JB, Donnelly JJ, Parker SE, Rhodes GH, Felgner PL et al. Heterologous protection against influenza by injection of DNA encoding a viral protein. Science 1993;259:1745-1749.

154. Fedson DS. Pandemic influenza and the global vaccine supply. Clin Infect Dis 2003;36:1552-1561.

155. Fedson DS. Vaccination for pandemic influenza and severe acute respiratory syndrome: common issues and concerns. Vaccine 2003;36:1562-1563.

156. World Health Organization. WHO update: international response to the inadvertent distribution of H2N2 influenza virus: destruction of virus panels proceedings. WHO 2005; disponible en: http://www.who.int/csr/disease/influenza/h2n2_2005_04_15/en/

157. Ford SM. Grabenstein JD. Pandemics, avian influenza A (H5N1), and a strategy for pharmacists. Pharmacotherapy 2006;26:312-322.

158. Lu JH, Long JX, Shao WX, Wei DP, Liw XF. Generation of attenuated H5N1 and H5N2 subtypes of influenza virus recombinants by reverse genetics system. Wei Sheng Wu Xue Bao 2005;45:53-57.

159. Poland GA, Rottinghaus ST, Jacobson RM. Influenza vaccines: a review and rationale for use in developed and underdeveloped countries. Vaccine 2001;19:2216-2220.

160. Anónimo. Antiviral drugs for prophylaxis and treatment of influenza. Obstet Gynecol 2005;105:427-429.

161. Stephenson I, Nicholson KG. Influenza: vaccination and treatment. Eur Respir J 2001;17:1282-1293.

162. The writing committee of the World Health Organization (WHO) Consultation on avian influenza A/H5 current concepts avian influenza A (H5N1) infection in humans. N Engl J Med 2005;353:1374-1385.

163. Yuen KY, Wong SSY. Human infection by avian influenza A H5N1. Hong Kong Med J 2005;11:189-199.

164. 164 Govorkova EA, Leneva IA, Goloubeva OG, Bush K, Webster RG. Comparison of efficacies of RWJ-270201, zanamivir, and oseltamivir against H5N1, H9N2, and other avian influenza viruses. Antimicrob Agents Chemother 2001;45:2723-2732.

165. Ward P, Small I, Smith J, Suter P, Dutkowski R. Oseltamivir (Tamiflu) and its potential for use in the event of an influenza pandemic. Antimicrob Agents Chemother 2005;55:15S-21S.

166. Nicholson KG, Aoki FY, Osterhaus AD, Trottier S, Carewicz O, et al. Efficacy and safety of oseltamivir in treatment of acute influenza: a randomised controlled trial. Neuraminidase Inhibitor Flu Treatment Investigator Group. Lancet 2000;355:1845-1850.

167. McClellan K, Perry CM. Oseltamivir: a review of its use in influenza. Drugs 2001;61:263-283.

168. Hayden FG, Gubareva LV, Monto AS, Klein TC, Elliott MJ et al. Inhaled zanamivir for the prevention of influenza in families. Zanamivir Family Study Group. N Engl J Med 2000;343:1282-1289.

169. Chotpitayasunondh T, Ungchhusak K, Hanshoworakui W, Chunsuthiwat S, Sawanpanyalert P et al. Human disease from influenza A (H5N1), Thailand 2004. Emerg Infect Dis 2005;11:201-209.

170. Ungchhusak K, Auwarakul P, Dowell SF, Kitphati R, Auanit W et al. Probable person-to person transmission of avian influenza A/(H5N1). N Engl J Med 2005;352:333-340.

171. Enders KO, Cheng PKC, Ng AYY, Hoan GTL, Lim WL. Influenza A H5N1 Detection. Emerg Infect Dis 2005;11:1303-1305.

172. Padhi S, Panigrahi PK, Mahapatra A, Mahapatra S. Avian influenza A (H5N1): a preliminary review. Indian J Med Microbiol 2004;22:143-146.

173. World Health Organization. WHO global Influenza preparedness plan: the role of WHO and recommendations for national measures before and during pandemics. Ginebra, Suiza: World Health Organization, 2005. Disponible en:http://www.who.int/csr/resources/publications/influenza/GIP_2005_5Eweb.pdf

174. WHO consultation on priority public health interventions before and during an influenza pandemic. Ginebra, Suiza: World Health Organization, 2004. (Document WHO/CDS/CSR/RMD/2004.9.). Disponible en:http://www.who.int/csr/disease/avian_influenza/consultation/en/

175. Secretaría de Salud. Plan de preparación y respuesta ante una pandemia de influenza. Secretaría de Salud 2005. Disponible en;http://www.dgepi.salud.gob.mx/pandemia/ppi.pdf