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2010, Number 1

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Rev Mex Patol Clin Med Lab 2010; 57 (1)

Recent advances in the diagnosis, epidemiology and prevention of influenza illness. Critical review

Carrada BT

Language: Spanish
References: 130
Page: 4-53
PDF size: 1521.44 Kb.


ABSTRACT

About 20% of children and 5% of adults develop symptomatic A or B influenza each year. The clinical course is affected by patient’s age, the degree of preexisting immunity, properties of the virus, comorbidities, immunosuppresion, pregnancy and smoking. Most infections are spread by virus-laden droplets expelled during coughing and sneezing, but fomites is another mode of transmission. Hemagglutinin facilitates attachment, of the virus to sialic acid receptors, viral replication is initiated at the ciliated epithelium, macrophages and pneumocytes type 2, the viral load rises to 103-107, TCID 50/mL in the nasopharyngeal wash, remains high for 24-72 h and falls by the fifth day. Viral virulence resides in type of hemagglutinin, but other factors such as non-structural protein-1, PB-2 and neuraminidase are also involved in pathogenicity, suggesting that severe haemorrhagic pneumonia is due to induction of and excess of cytokines leading to tissue damage and death. The extent of influenza mortality has been tracked by counting deaths caused dy pneumonia-influenza, however, they offer less sensitive data than those of all-cause mortality. Influenza morbidity can be quantified by combining clinical illness diagnosis with laboratory confirmation. Aquatic birds are main reservoir of influenza A viruses transmission to humans, pigs, domestic birds and other animals has been demonstrated by phylogenetic analysis of viral nucleoproteins. Inactivated vaccines are the prime means to prevent influenza, but cold adapted virus-vaccines appears to offer broader protection in children. Oral oseltamivir and inhaled zanamivir have shown clinical efficacy in preventing and treating influenza-illness.


REFERENCES

  1. Salomon R, Webster RG. Cell 2000; 136: 402-410.

  2. Nicholson KG. Human influenza. In: Nicholson KG, Hay AJ, Webster RG (eds). Textbook of influenza. Boston: Blackwell Science; 1998. p. 222-246.

  3. Kilbourne ED. The influenza viruses and influenza London: Academic Press; 1975. p. 1-539.

  4. Shope RE. Swine influenza 1. Experimental transmission and pathology. J Exp Med 1931; 54: 349-372.

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

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

  7. Magili TP. A virus from cases of influenza-like upper. Respiratory infection. Proc Soc Exp Biol Med 1940; 45: 162-164.

  8. Burnet FM. Growth of influenza virus in the allantoic cavity of the chick embryos. Aus J Exp Biol Med Sci 1941; 19: 291-295.

  9. Hirst GK. The agglutination of red cells by allantoic fluid of chick embryos infected with influenza virus. Science 1941; 94: 22-23.

  10. Laver WG. Structural studies of the protein subunits from three strains of influenza virus. J Mol Biol 1964; 9: 109-124.

  11. Laver WG, Webster RG. Studies on the origin of pandemic influenza. 2. Peptide maps of the light and heavy polypeptide chains from the hemagglutinin subunits of A2-influenza viruses isolated before and after the appearance of Hong-Kong influenza. Virology 1972; 48: 445-447.

  12. Kilbourne ED. The molecular epidemiology of influenza. J Infect Dis 1973; 127: 478-487.

  13. Webster RG, Bean WJ, Gorman OT, Chambers TM, Kawoka J. Evolution and ecology of influenza A viruses. Microbiol Rev 1992; 56: 152-159.

  14. Nicholson KL, Wood JM, Zambon M. influenza Seminar). Lancet 2003; 362: 1733-1745.

  15. Manjarrez-Zavala ME, Arenas-López G. Virus influenza: Enigma del pasado y del presente. Rev Inst Nal Enf Resp Mex 1999; 12: 290-299.

  16. Nicholson KG, Webster RG, Hay AJ (eds). Textbook of Influenza. Oxford: Blackwell Science; 1998.

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

  18. Ito TY, Kawoka J. Host-range barrier of influenza A viruses. Vet Microbiol 2000; 74: 71-75.

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

  20. Sway DE. Undertandig the ecology and epidemiology of avia influenza viruses: implication for zoonotic potential. Chapter 6. In: Brown C, Bolin C. Emerging Diseases of Animals. Washington DC: ASM Press; 2000.

  21. Zimmer SM, Burke DS. Historical perspective-emergence of influenza A (H1 N1) viruses. N Engl J Med 2009; 361: 279-285.

  22. Morens DM, Taubenberger JK, Fauci AS. The persistent legacy of the 1918 influenza virus. N Engl J Med 2009; 361: 225-229.

  23. Tambaut A, Pybus OG, Nelson MI, Viudoute C, Taubenberger JK, Holmes EC. The genomic and epidemiological dynamics of human influenza virus. Nature 2008; 453: 615-619.

  24. Shope RE. The incidence of neutralizing antibodies for swine influenza virus in the sera of human beings of different ages. J Exp Med 1936; 36: 669-684.

  25. Stevens J, Blixt O, Tumpey TM, Tauberger JK, Paulson JC, Wilson IA. Structure and receptor specificity of the hemaglutinin from an H5 N1 influenza virus. Science 2006; 312: 404-410.

  26. Nelson MI, Viboud C, Simonsen L. Multiple reassortement events in the evolutionary history of H1 N1 influenza A virus since 1918. Plos Palhog 2008; 360: 2605-2615.

  27. Wright PF, Newman G, Kawoka J. Orthomyxovirus. In: Knipe DM, Howley PM. eds. Fields Virology. 5th ed. Philadelphia: Lippincott Williams and WiIkins; 2007. p. 1961-2740.

  28. Novel Swine-Origin Influenza A (H1 N1) Virus Investigation Team. Emergence of a novel swine-origen influenza A (H1 N1) virus in humans. N Engl J Med 2009; 360: 2605-2615.

  29. Garten RJ, Davis CT, Russell CA. Antigenic and genetic characteristic of swine – origen 2009 A (H1 N1) influenza virus circulating in humans. Science 2009; 8-16.

  30. Newman AP, Reisdorf E, Beinemann J. Human case of swine influenza A (H2 N1) triple reassortant virus infection, Wisconsin. Emerg Infect Dis 2008; 14: 1470-1472.

  31. Ramírez SH. Aislamiento e identificación del virus de la influenza porcina en México. Tesis de Licenciatura. México, DF: Fac Med Vet Zoot, UNAM; 1981.

  32. Cortez AE. Frecuencia del virus de la influenza porcina en pulmones de cerdos afectados por neumonía. Tesis de Licenciatura. México, DF: Fac Med Vet Zoot, UNAM; 1985.

  33. Rodríguez TJ, Ramírez MH, Carreón NR, Mercado GC. Muestreo serológico a nivel de rastro para detectar anticuerpos contra el virus de la influenza porcina. Vet Mex 1996; 27: 17-21.

  34. Álvarez-Fleitez M, Rodríguez BJC, Ciprián-Carrasco A, Rodríguez GL, Ayora TG, Segura CJ. Perfil serológico del virus de influenza porcina, Mycoplasma hypopeumoniae, Actinobacillus pleuropneumoniae, en granjas de Yucatán, México. Vet Mex 2004; 35: 295-305.

  35. Writing Committee of the Second World Health Organization Consultation on Clinical Aspects of Human Infection with Aviar Influenza A (H5 N1) Virus. N Engl J Med 2008; 358: 261-273.

  36. Webster RG, Govorkona EA. H5 N1 Influenza-continuing evolution and spread. N Engl J Med 2006; 355: 2174-2177.

  37. Peiris JS, Yu WC, Leung CW. Re-emergence of fatal human influenza A subtype H5 N1 disease. Lancet 2004; 363: 617-619.

  38. Hulse PDJ, Sturm RKM, Humberd J. Role of domestic duck in the progation and biological evolution of highly pathogenic H5-N1 influenza viruses in Asia. Proc Natl Acad Sci USA 2005; 102: 10682-10687.

  39. Noble GR. Epidemiological and clinical aspects of influenza. In: Beare AS ed. Basic and applied influenza research. Boca Raton, Fl: CRC Press; 1982. p. 11-50.

  40. Taubenberger JK, Morens DM. Pandemic influenza – including a risk assessment of H5 N1. Rev Sci Tech 2009; 28: 187-202.

  41. Parrish CR, Holmes EC, Morens DM. Cross-species virus transmission and emergence of new epidemic diseases. Microbiol Mol Biol Rev 2008; 72: 457-70.

  42. Wright PF, Ross KB, Thompson J, Karzon DT. Influenza A infection in young children. N Engl J Med 1977; 296: 829-334.

  43. Wright PF, Bryant JD, Karzon DT. Comparison of Influenza B/Hong Kong virus infection among infants, children, and young adults. J Infect Dis 1980; 141: 430-435.

  44. Woodwall J, Rowson KEK, Mc Donald JC. Age and Asian influenza. BMJ 1957; 1958: 1316-1318.

  45. Paisley JW, Bruhn FW, Lauer BA, Mc Intoshk L. Type A 2 influenza virus infection in children. Am J Dis Child 1978; 132: 34-36.

  46. Price DA, Postlethwaite RJ, Longson M. Influenza virus and gastrointestinal symptoms in young children. Clin Pediatr 1976; 15: 362-367.

  47. Dagan R, Hall CB. Influenza A virus infection imitating bacterial sepsis in early infancy. Pediatr Infect Dis J 1984; 3: 218-221.

  48. Noble GR. Epidemiological and clinical aspects of influenza. In: Beare AS ed. Basic and applied influenza research. Boca Raton: CRC Press; 1982. p. 11-50.

  49. Neuzil KM, Reed GW, Mitchell EF, Simonsen L, Griffin MR. Impact of influenza on acute cardiopulmonary hospitalization in pregnant women. Am J Epidemiol 1998; 148: 1094-1102.

  50. Ferson MJ, Morton JR, Robertson PW. Impact of influenza on morbidity in children with cystic fibrosis. J Pediatr Child Health 1991; 27: 308-311.

  51. Minor ME, Dick EC, Baker JW, Ouellette JJ, Cohen M, Reed CE. Rhinovirus and influenza A infections as precipitants of asthma. Am Rev Respir Dis 1976; 113: 149-153.

  52. Fujimoto S, Kobayashi M, Uemura O. PCR on cerebrospinal fluid to show influenza associated acute encephalopathy or encephalitis. Lancet 1998; 352: 873-875.

  53. Mc Cullers JA, Facchini S, Chesney PJ, Webster PG. Influenza B-virus encephalitis. Clin Infect Dis 1999; 28: 898-900.

  54. Mc Donald KL, Osterholm MT, Hedberg CW. Toxic shock syndrome: a newly recognized complication of influenza and influenza-like illness. JAMA 1987; 257: 1053-1058.

  55. Gerberding JL, Morgan JG, Shepard JA, Kradin RL. Case 9-2004: An 18 year-oldman with respiratory symptoms and shock. N Engl J Med 2004; 350: 1236-1247.

  56. Ebell MH, White LL, Casault T. A systematic review of the history and physical examination to diagnose influenza. J Am Board Fam Pract 2004; 17: 1-5.

  57. Carrat F, Tachet A, Rouzioux C, Housset B, Valeron AJ. Evaluation of clinical case definition in influenza: detailed investigation of patients during the 1955-1996 epidemic in France Clin Infec Dis 1999; 28: 283-290.

  58. Deville WL, Buntix F. Guidelines for conducting systematic reviews of studies evaluating the accuracy of diagnostic tests, In: Knotterus JA (ed). The Evidence Base of Clinical diagnosis. London, England: BMJ Books; 2002. p. 156-159.

  59. Rodríguez WJ, Schwartz RH, Thome MM. Evaluation of diagnostic tests for influenza in a pediatric practice. Pediatr Infect Dis J 2002; 21: 193-196.

  60. Magnard C, Valette M, Aymard M, Linda B. Comparison of two nested PCR, cell culture, and antigen detection for the diagnosis of upper respiratory tract infections due to influenza viruses. J Med Virol 1999; 59: 215-220.

  61. Call SA, Vollenweider MA, Hornung CA, Simel DL, Mc Kinney WP. Does This Patient Have Influenza JAMA 2005; 293: 987-997.

  62. Mizgerd JP. Acute Lower Respiratory Tract Infection. N Engl J Med 2008; 358: 716-727.

  63. Cheung CY, Poon LLM, Lau AS, Luk W, Lau YL, Shhortridge KF y cols. Induction of proinflammatory cytokines in human macrophages by influenza A (H5-N1) viruses: a mechanism for the unusual severity of human disease. Lancet 2002; 360: 1831-1837.

  64. Lucke B, Wight T, Kime E. Pathologic anatomy and Bacteriology of influenza: epidemic of autumn, 1918. Arch Intern Med 1919; 24: 154-237.

  65. Oseasohn R, Adelson L, Kaji M. Clinic pathologic study of thirty three cases of Asian influenza. N Engl J Med 1959; 260: 509-518.

  66. Yeldandi A, Colby TV. Pathologic features of lung biopsy specimens from influenza pneumonia cases. Hum Pathol 1994; 25: 47-53.

  67. Craghead JE. Pathology and pathogenesis of human viral disease. San Diego, Cal: Academic Press; 2000.

  68. Mulder J, Hers JF. Influenza. The Netherlands: Wolters Noordhoff Pub Gronigen, 1972: 1-300.

  69. Gu J, Xie Z, Gao Z. H5-N1 infection of the respiratory tract and beyond: a molecular pathology study. Lancet 2007; 370: 1137-1145.

  70. Uiprasertkul M, Kitphati TC, Pathavatha P. Apoptosis and pathogenesis of avian influenza A (H5-N1) virus in humans. Emerg Infect Dis 2007; 13: 708-712.

  71. Neg WF, Lam WWL, Ng TK, Lee KC. The comparative pathology of severe acute respiratory syndrome and avian influenza A subtype H5-N1 a review. Hum Pathol 2006; 37: 381-390.

  72. Shinya K, Ebina M, Yamada S, Ono M, Kasai N, Kawoka Y. Avian flu: influenza virus receptors in the human airway. Nature 2006; 440: 435-436.

  73. He X, Zhou J, Bartlam M, Zhang R, Ma J, Lou Z et al. Crystal structure of the polymerase PA(C)-PB-1. 2008; 454: 1123-1126.

  74. Cheung CY, Poon LL, Lau AS, Lau Y L, Shortridge KF y cols. Induction of proinflammatory cytokines in human macrophages by influenza A (H5-N1) viruses: a mechanism for the unusual severity of human disease? Lancet 2002; 360: 1831-1837.

  75. De Jong MD, Simmons CP, Thanh TT, Hien VM, Smith GJ, Chau TN et al. Fatal outcome of influenza A (H5-N1) is associated with high viral load and hypercytokinemia. Nat Med 2006; 12: 1203-1207.

  76. Chan MC, Cheung CY, Chui WH, Tsao SW, Nicholls JM, Chan YO et al. Proinflammatory cytokine responses induced by influenza A (H5-N1) viruses in primary human alveolar and bronchial epithelial cells. Respir Res 2005; 6: 135-136.

  77. Kash JC, Tumpey TM, Proll SC, Carter V, Perwitasari O, Thomas MJ et al. Genomic analysis of increased host immune and cell death responses induced by 1918 influenza virus. Nature 2006; 443: 578-581.

  78. Tampey TM, Szretter KJ, Van Hoeven N, Katz JM, Kochs G, Haller O et al. The Mxl gene protects mice against the pandemic 1918 and highly lethal human H5-N1 influenza viruses. J Virol 2007; 81: 10818-10821.

  79. Mc Auley JL, Hornung F, Boyd KL, Smith AM, Raelene McKeon, Bennik J et al. Expression of the 1918 Influenza A virus PB1-F2 enhances the pathogenesis of viral and bacterial pneumonia. Cell Host Microbe 2007; 2: 240-249.

  80. Pichlmair A, Schuls O, Tan CP, Naslund TI, Liljestron P, Weber F et al. RIG-L mediated antiviral responses to single stranded RNA bearing 5¹-phosphates. Science 2006; 314: 997-1001.

  81. Ludwig S, Pleschka S, Planz O, Wolff A. Ringing the alarm bell: Signaling and apoptosis in influenza virus infected cells. Cell Microbiol 2006; 8: 375-386.

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

  83. Eickhoff TC, Sherman IL, Serflig RE. Observations on excess mortality associated with epidemic influenza. JAMA 1961; 176: 776-782.

  84. Glezen WP. Serious morbidity and mortality associated with influenza epidemics. Epidemiol Rev 1982; 4: 25-44.

  85. Thompson WW, Shay DK, Weintraub E. Mortality associated with influenza and respiratory syncytial virus in the United Stattes. JAMA 2003; 289: 179-186.

  86. Monto AS. Epidemiology and virology of influenza J illness. Amer J Manag Care 2009; 6: S255-S264.

  87. Griffin NR, Neuzil KM. Global Implications of Influenza in Hong Kong. N Engl J Med 2002; 347: 2159-2162.

  88. Dauer CC, Serfling RE. Mortality from influenza 1957-1958 and 1959-1960. Am Rev Respir Dis 1961; 83 (suppl): 15-28.

  89. Serflig RE. Methods for current statistical analysis of excess pneumonia-influenza deaths. Public Health Rep 1963; 78: 494-506.

  90. Thopson WW, Weintraub E, Dhankhar P, Cheng PY, Brammer L, Meltzer MI et al. Estimates of US influenza associated deaths made using four different methods. Influenza and Other Respiratory Viruses 2009; 3: 37-49. (www.blackwellpublishing.com/influenza).

  91. Simonsen L, Fukuda K, Schonberger LB, Cox NJ. The impact of influenza epidemics on hospitalizations. J Infect Dis 2000; 181: 831-837.

  92. Simonsen L, Clarke MJ, Schonberger LB, Arden NH, Cox NJ, Fukuda K. Pandemic versus epidemic influenza mortality: A pattern of changing age distribution. J Infect Dis 1998; 178: 53-60.

  93. Glezen WP, Couch RB. Interpandemic influenza in the Houston area, 1974-76. N Engl J Med 1978; 298: 587-592.

  94. Fox JP, Hall CE, Cooney MK. Influenza virus infection in Seattle families, 1975-1979. I. Study design, methods and the occurrence of infections by time and age. Am J Epidemiol 1982; 116: 212-227.

  95. Chin TDY, Foley JF, Doto IL. Morbidity and mortality characteristic of Asian strain Influenza Public Health Rep 1960; 75: 149-158.

  96. Monto AS, Kioumehr F. The Tecumseh study of respiratory illness. Ix Ocurrence of influenza in the community 1966-1971. Am J Epidemiol 1975; 102: 553-563.

  97. Izurieta HS, Thompson WW, Kramarz P, Shay DK, Davis RL, De Stephano F y cols. Influenza and the rates of hospitalization for respiratory disease among infants and young children. N Engl J Med 2000; 342: 232-239.

  98. Neuzil KM, Mellen BG, Wright PF, Mitchell EF, Griffin MR. The effect of influenza on hospitalization, outpatients visits, and courses of antibiotics in children. N Engl J Med 2000; 342: 225-231.

  99. Collins SD, Lehmann J. Excess deaths from influenza and pneumonia band from important chronic diseases during the period, 1918-51. Washington DC: Government Printing Office, 1953.

  100. Meier CR, Napalkou PN, Wegmiiller Y, Jefferson T, Jick H. Population based study on incidence, risk factors, clinical complications and drug-utilization associated with influenza in the United Kingdom. Eur J Clin Microbiol Infect Dis 2000; 19: 834-842.

  101. Frost WH. The epidemiology of influenza. JAMA 1919; 73: 313-318.

  102. Francis T Jr. The new acquaintance. Ann Intern Med 1953; 39: 203-221.

  103. Walker OJ. Pathology of influenza pneumonia. J Lab Clin Med 1919; 5: 154-175.

  104. Taubenberger JK, Reid AH, Lourens RM, Wang R, Jin G, Fanning TG. Integrating historical, clinical and molecular genetic data in order to explain the origen and virulence of the 1918 Spanish Influenza virus. Philos Trans R Soc London Biol Sci 2001; 356: 1829-1839.

  105. Reid AH, Fannimg TG, Hultin JU. Origin and evolution of the 1918 “Spanish” influenza virus hemagglutinin gene Proc Natl Acad Sci USA 1999; 96: 1651-1656.

  106. Reid AH, Taubenberger JK, Fanning TG. Evidence of an absence: the genetic origins of the 1918 pandemic influenza virus. Nat Rev Microbiol 2004; 2: 909-914.

  107. Taubenberger JK, Reid AH, Lourens RM, Wang R, Jin G, Fanning TG. Characterization of the 1918 influenza virus polymerase genes. Nature 2005; 437: 889-893.

  108. Muños FM, Galasso GJ, Gwaltney JM, Hayden FG, Murphy B, Webster R et al. Current research on influenza and other respiratory viruses II International Symposium. Antiviral Res 2000; 46: 91-124.

  109. Kobasa DF, Takada A, Shinga K. Enhanced virulence of influenza A viruses with haemagglutinin of 1918 pandemic virus. Nature 2004; 431: 703-707.

  110. Taubenberger JK, Reid AH, Krafft AE, Bijwaard KE, Fanning TG. Initial genetic characterization of the 1918 «Spanish» influenza virus. Science 1997; 275: 1793-1796.

  111. Hoft DF, Belshe RB. The genetic archeology of influenza. N Engl J Med 2004; 351: 2550-51.

  112. Belshe R. The origins of pandemic influenza lessons from the 1918 virus. N Engl J Med 2005; 353: 2209-2211.

  113. Taubenberger JR, Reid AH, Lourens RM, Wang R, Jin G, Fanning TG. Characterization of 1918 influenza virus polymerase gene. Nature 2005; 437: 887-893.

  114. Tumpey TM, Basler CF, Aguilar PU. Characterization of the reconstructed 1918 Spanish influenza pandemic virus. Science 2005; 310: 77-80.

  115. Noble GR. Epidemiological and clinical aspect of influenza. In: Beare AS (ed). Basic and Applied Research. Boca Raton, FL: CRC; 11-50.

  116. Glezen WP. Serious Morbidity and Mortality associated with influenza epidemics. Epidemiol Rev 1982; 4: 25-44.

  117. Stuart Harris CH, Schild GC, Oxford JS. Influenza The Viruses and the Disease. 2a ed. Victoria, Can: Eduard Arnold Ed; 1985. p. 118-38.

  118. Andreasen V, Viboud C, Simonsen L. Epidemiologic characterization of 1918 influenza pandemic summer wave in Copenhague: Implications for pandemic control strategies. J Infect Dis 2008; 197: 270-278.

  119. Navarrete LRC, Betancourt CM, Murguía MP. Panorama de la mortalidad por infecciones respiratorias en México durante el año 2000. Una identificación de municipios de riesgo. Epidemiología (Mex) 2003; 20 (11): 1-3.

  120. Olsen CW. The emergence of novel swine influenza viruses in North America. Virus Res 2002; 85: 199-210.

  121. Vincent AL, Ma W, Lager KM, Yanke BH, Richt JA. Swine influenza viruses: A North American Perspective. Adv Virus Res 2008; 72: 127-154.

  122. Novel Swine Origin Influenza A (H1-N1) virus in humans. N Engl J Med 2009; 360: 2605-2615.

  123. Chowell G, Bertozzi E, Colchero M A, Lopez Gatell H, Alpuche Aranda C, Hernández M, Miller MA. Severe Respiratory Disease Concurrent with circulation of H1-N1 Influenza. N Engl J Med 2009; 361: 674-679.

  124. Osterholm MT. Preparing for Next Pandemic. N Engl J Med 2005; 352: 1839-1842.

  125. Johnson NP, Mueller J. Updating the account global mortality of 1918-1920 «Spanish» influenza pandemic. Bull Hist Med 2002; 76: 105-115.

  126. Miller MA, Viboud C, Olson DR, Grais RF, Rabaa MA, Simonsen L. Prioritization of influenza pandemic vaccination to minimize years of life lost. J Infect Dis 2006; 12: 661-668.

  127. Newman AP, Reisdorf E, Beinemann J. Human case of swine influenza A (H2-N1) triple reassortant virus infection Wisconsin. Emerg Infect Dis 2008; 14: 1470-1472.

  128. Karasin AI, Schutten MM, Cooper LA. Genetic characterization of H3-N2 influenza viruses isolated from human and reassortant virus genotypes. Virus Res 2006; 68: 71-85.

  129. Myers KP, Olsen CW, Gray GC. Cases of swine influenza in humans: A review of the literature. Clin Infect Dis 2007; 44: 1084-1088.

  130. Pensaert M, Ottis K, Vandeputte J, Kaplan MM, Bachman PA. Evidence for the natural transmission of influenza A virus from wild ducks to swine and its potential importance to man. Bull World Health Organ 1981; 59: 75-78.




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