Advertisement

Avian Influenza: Recent Epidemiology, Travel-Related Risk, and Management

  • Rajeka Lazarus
  • Poh Lian LimEmail author
Tropical, Travel and Emerging Infections (L Chen, Section Editor)
Part of the following topical collections:
  1. Topical Collection on Tropical, Travel and Emerging Infections

Abstract

H5N1 influenza continues to smolder in Southeast Asia over the past 5 years, but the emergence of H7N9 in China in 2012 raised concerns for a new avian influenza threat. In contrast with H5N1 with over 650 confirmed cases over 11 years, H7N9 has infected over 450 persons within 2 years. The case fatality rate for H7N9 (35 %) is lower than for H5N1 (60 %) or H10N8 (67 %) but is comparable to that for the Middle East respiratory syndrome coronavirus (MERS CoV), another emerging zoonosis with travel-associated importations. Exposure to poultry and fomites are considered the likely sources of infection for H7N9, H5N1, and H10N8, with limited human-to-human transmission in close contacts. Most cases have occurred in local populations of affected countries, and travel-related risk can be mitigated by avoiding exposure. Vaccines, antivirals, and other therapeutics remain in development stage or of modest benefit for dangerous infections carrying high morbidity and mortality.

Keywords

Avian influenza H5N1 H7N9 Influenza Travel Therapy Epidemiology Emerging infections Zoonoses 

Notes

Compliance with Ethics Guidelines

Conflict of Interest

Poh Lian Lim has no disclosures relevant to this work.

Human and Animal Rights and Informed Consent

This article does not contain any studies with human or animal subjects performed by the authors.

References

Papers of particular interest, published recently, have been highlighted as: •• Of major importance

  1. 1.
    H5N1 avian influenza: timeline of major events 13 December 2011 http://www.who.int/influenza/human_animal_interface/avian_influenza/H5N1_avian_influenza_update.pdf. Accessed 2 July 2014.
  2. 2.
    Emergence of avian influenza A(H7N9) virus causing severe human illness—China February–April 2013. MMWR. 2013;62(18):366–371.Google Scholar
  3. 3.
    World Health Organisation. Influenza monthly risk assessment. Available at http://www.who.int/influenza/human_animal_interface/HAI_Risk_Assessment/en/. Accessed 2 July 2014.
  4. 4.
    WHO risk assessment of human infection with avian influenza A(H7N9) virus http://www.who.int/influenza/human_animal_interface/influenza_h7n9/140225_H7N9RA_for_web_20140306FM.pdf?ua=1. Accessed 2 July 2014.
  5. 5.
    Isolation of avian influenza A(H5N1) viruses from humans—Hong Kong, May-December 1997. MMWR. 1997;46(50):1204–1207.Google Scholar
  6. 6.
    First N. American H5N1 bird flu death confirmed in Canada. BBC news http://www.bbc.com/news/world-us-canada-25662730. Accessed 2 July 2014.
  7. 7.
    Xiang N, Havers F, Chen T, Song Y, Tu W, Li L, et al. Use of national pneumonia surveillance to describe influenza A(H7N9) virus epidemiology, China, 2004–2013. Emerg Infect Dis. 2013. doi: 10.3201/eid1911.130865.Google Scholar
  8. 8.
    Gao R, Cao B, Hu Y, et al. Human infection with a novel influenza virus. N Engl J Med. 2013;368:1888–97.CrossRefPubMedGoogle Scholar
  9. 9.
    Ip DK, Liao Q, Wu P, et al. Detection of mild to moderate influenza A/H7N9 infection by China’s national sentinel surveillance system for influenza-like illness: case series. BMJ. 2013;24:346:f3693.Google Scholar
  10. 10.
    WHO case definitions for human infections with influenza A(H5N1) virus 26 August 2006 http://www.who.int/influenza/resources/documents/case_definition2006_08_29/en/. Accessed 2 July 2014.
  11. 11.
    Wang TT, Parides MK, Palese P. Seroevidence for H5N1 influenza in human: meta-analysis. Science. 2012;335(6075):1463. doi: 10.1126/science.1218888.CrossRefPubMedCentralPubMedGoogle Scholar
  12. 12.
    Tian B, Zhou T, Shu Y. Serologic study for influenza A (H7N9) among high-risk groups in China. N Engl J Med 368;24: 2339–2340.Google Scholar
  13. 13.
    Yuen KY, Chan PK, Peiris M, et al. Clinical features and rapid viral diagnosis of human disease associated with avian influenza A/H5N1 virus. Lancet. 1998;351:457–71.CrossRefGoogle Scholar
  14. 14.
    Li Q, Zhou L, Zhou M. Epidemiology of human infections with avian influenza A(H7N9) virus in China. N Engl J Med. 2014;370:520–32.CrossRefPubMedGoogle Scholar
  15. 15.
    Mounts AW, Kwong H, Lzurieta HS, et al. Case control study of risk factors for avian influenza A (H5N1) disease Hong Kong 1997. J Infect Dis. 1999;180:505–8.CrossRefPubMedGoogle Scholar
  16. 16.
    Ai J, Huang Y, Xu K, Ren D, Qi X, Ji H, Ge A, Dai Q, Li J, Bao C, Tang F, Shi G, Shen T, Zhu Y, Zhou M, Wang H. Case-control study of risk factors for human infection with influenza A(H7N9) virus in Jiangsu Province, China, 2013. Euro Surveill. 2013;18(26). Available online: http://www.eurosurveillance.org/ViewArticle.aspx?ArticleId=20510.
  17. 17.
    Ungchusak K, Auewarakul P, Dowell SF, et al. Probably person-to-person transmission of avian influena A (H5N1). N Engl J Med. 2005;352(4):333–40.CrossRefPubMedGoogle Scholar
  18. 18.
    Katz JM, Lim W, Bridges CB. Antibody response in individuals infected with avian influenza A (H5N1) viruses and detection of anti-H5 antibody among household and social contacts. J Infect Dis. 1999;180(6):1763–70.CrossRefPubMedGoogle Scholar
  19. 19.
    Cooper MC. The elderly traveller. Travel Med Infect Dis. 2006;4(3–4):218–22.CrossRefPubMedGoogle Scholar
  20. 20.
    Chen H, Yuan H, Gao R. Clinical and epidemiological characteristics of a fatal case of avian influenza A H10N8 virus infection: a descriptive study. Lancet 22;383(9918):714–2.Google Scholar
  21. 21.
    World Health Organisation. Global influenza program surveillance network evolution of H5N1 avian influenza viruses in Asia. Emerg Infect Dis. 2005;11(10):1515–21.CrossRefGoogle Scholar
  22. 22.
    Chen Y, Liang W, Yang S. Human infections with the emerging avian influenza A H7N9 virus from wet market poultry: clinical analysis and characterisation of viral genome. Lancet. 2013;381:1916–25.CrossRefPubMedGoogle Scholar
  23. 23.
    Xu R, Vries R, Zhu X, et al. Preferential recognition of avian-like receptors in human influenza A H7N9 viruses. Science. 2013;342:1230–4.CrossRefPubMedCentralPubMedGoogle Scholar
  24. 24.
    Yang H, Carney P, Chang JC, Villanueva J, Stevens J. Structural analysis of the hemagglutinin from the recent 2013 H7N9 influenza virus. J Virol. 2013;87(22):12433–46.CrossRefPubMedCentralPubMedGoogle Scholar
  25. 25.
    Russell CA, Fonville JM, Brown AE, Burke DF, Smith DL, James SL, et al. The potential for respiratory droplet-transmissible A/H5N1 influenza virus to evolve in a mammalian host. Science. 2012;336(6088):1541–7.CrossRefPubMedCentralPubMedGoogle Scholar
  26. 26.
    Gao HN, Lu HZ, Cao B, et al. Clinical findings in 111 cases of influenza A (H7N9) virus infection. N Engl J Med. 2013;368:2277–85.CrossRefPubMedGoogle Scholar
  27. 27.
    The Writing Committee of the World Health Organization (WHO). Consultation on human influenza A/H5N1 avian influenza A (H5N1) infection in humans. N Engl J Med. 2005;353:1374–85.CrossRefGoogle Scholar
  28. 28.
    Belser JA, Bridges CB, Katz JM, Tumpey TM. Past, present, and possible future human infection with influenza virus A subtype H7. Emerg Infect Dis. 2009;15(6):859–65.CrossRefPubMedCentralPubMedGoogle Scholar
  29. 29.
    Wang Q, Zhang Z, MD, Shi Y. Emerging H7N9 influenza A (novel reassortant avian-origin). Pneumonia: Radiol Find Radiol Vol 268 (3): 882–9.Google Scholar
  30. 30.
    Feng F, Jiang Y, Yuan M, Shen J, Yin H, et al. Association of radiologic findings with mortality in patients with avian influenza H7N9 pneumonia. PLoS One. 2014;9(4):e93885. doi: 10.1371/journal.pone.0093885.CrossRefPubMedCentralPubMedGoogle Scholar
  31. 31.
    Yu H, Cowling BJ, Feng L, et al. Human infection with avian influenza A H7N9 virus: an assessment of clinical severity. Lancet. 2013;382:138–45.CrossRefPubMedCentralPubMedGoogle Scholar
  32. 32.
    To KF, Chan PK, Chan KF. Pathology of fatal human infection associated with avian influenza A H5N1 virus. J Med Virol. 2001;63(3):242–6.CrossRefPubMedGoogle Scholar
  33. 33.
    de Jong MD, Simmons CP, Thanh TT, et al. Fatal outcome of human influenza A (H5N1) is associated with high viral load and hypercytokinemia. Nat Med. 2006;12(10):1203–7.CrossRefPubMedCentralPubMedGoogle Scholar
  34. 34.
    Zhou J, Wang D, Gao R et al. Biological features of novel avian influenza A (H7N9) virus. Nature 499:500–3.Google Scholar
  35. 35.
    Jefferson T, Jones MA, Doshi P, et al. Neuraminidase inhibitors for preventing influenza in healthy adults and children. Cochrane Database Syst Rev. 2012;1, CD008965. doi: 10.1002/14651858.CD008965.pub4.PubMedGoogle Scholar
  36. 36.
    Muthuri SG, Venkatesan S, Myles PR, et al. Effectiveness of neuraminidase inhibitors in reducing mortality in patients admitted to hospital with influenza A H1N1 virus infection: a meta-analysis of individual participant data. Lancet Respir Med. 2014;2(5):395–404.CrossRefPubMedGoogle Scholar
  37. 37.••
    Adisasmito W, Chan PK, Lee N. Effectiveness of antiviral treatment in human influenza A(H5N1) infections: analysis of a Global Patient Registry. J Infect Dis. 2010;202(8):1154–60 (in the absence of a randomized controlled study this observational study provides the most formative evidence for the effectiveness of neuraminidase inhibitors in avian influenza).CrossRefPubMedGoogle Scholar
  38. 38.
    Centres for Disease Control and Prevention. Interim guidance on the use of antiviral agents for treatment of human infections with avian influenza A (H7N9 virus. Available at: http://www.cdc.gov/flu/avianflu/h7n9-antiviral-treatment.htm. Accessed 2 July 2014.
  39. 39.
    Govorkova EA, Ilyushina NA, Boltz DA, Douglas A, Yilmaz N, et al. Efficacy of oseltamivir therapy in ferrets inoculated with different clades of H5N1 influenza virus. Antimicrob Agents Chemother. 2007;51:1414–24.CrossRefPubMedCentralPubMedGoogle Scholar
  40. 40.
    de Jong MD, Tran TT, Truong HK, et al. Oseltamivir resistance during treatment of influenza A (H5N1) infection. N Engl J Med. 2005;353(25):2667–72.CrossRefPubMedGoogle Scholar
  41. 41.
    Yeh KM, Chiueh TS, Siu LK, et al. Experience of using convalescent plasma for severe acute respiratory syndrome among healthcare workers in a Taiwan hospital. J Antimicrob Chemother. 2005;56(5):919–22.CrossRefPubMedGoogle Scholar
  42. 42.
    Mupapa K, Massamba M, Kibadi K, et al. Treatment of Ebola hemorrhagic fever with blood transfusions from convalescent patients. International Scientific and Technical Committee. J Infect Dis. 1999;179 Suppl 1:s18–23.CrossRefPubMedGoogle Scholar
  43. 43.
    Hung IF, To KK, Lee KL, et al. Convalescent plasma treatment reduced mortality in patients with severe pandemic influenza A (H1N1) 2009 virus infection. Clin Infect Dis. 2011;52(4):447–56. doi: 10.1093/cid/ciq106.CrossRefPubMedGoogle Scholar
  44. 44.
    Herbreteau CH, Jacquot F, Rith S, Vacher L et al. Specific polyclonal F(ab′)2 neutralize a large panel of highly pathogenic avian influenza A viruses (H5N1) and control infection in mice. Immunotherapy 2014.Google Scholar
  45. 45.
    Hien ND, Ha HN, Van NT, et al. Human infection with highly pathogenic avian influenza virus (H5N1) in northern Vietnam, 2004–2005. Emerg Infect Dis. 2009;15(1):19–23.CrossRefPubMedCentralPubMedGoogle Scholar
  46. 46.
    Lo YC, Chen WC, Huang WT, Lin YC, Liu MC, Kuo HW, Chuang JH, Yang JR, Liu MT, Wu HS, Yang CH, Chou JH, Chang FY. Surveillance of avian influenza A(H7N9) virus infection in humans and detection of the first imported human case in Taiwan, 3 April to 10 May 2013. Euro Surveill. 2013;18(20). Available online: http://www.eurosurveillance.org/ViewArticle.aspx?ArticleId=20479.
  47. 47.
    Centres for Disease Control. H7N9 case detected in Malaysia. Available at: http://www.cdc.gov/flu/news/h7n9-case-malaysia.htm. Accessed 17 July 2014.
  48. 48.
    CNN News. Hong Kong on high alert after first human case of H7N9 bird flu. Available at: http://edition.cnn.com/2013/12/03/world/asia/hong-kong-h7n9-case/. Accessed 17 July 2014.
  49. 49.
    World Health Organisation Global Alert and Response. Available at http://www.who.int/csr/don/2014_06_10_h7n9/en/.
  50. 50.
    Centres of Disease Control. Avian flu travel information. Available at: http://wwwnc.cdc.gov/travel/page/avian-flu-information.
  51. 51.
    World Health Organisation. Stop the spread measures to stop the spread of highly pathogenic bird flu at its source 2005. Available at: http://whqlibdoc.who.int/wpro/2005/StoptheSpread_eng.pdf.
  52. 52.
    Chan PK. Outbreak of avian influenza A(H5N1) virus infection in Hong Kong in 1997. Clin Infect Dis. 2002;34 Suppl 2:s58–64.CrossRefPubMedGoogle Scholar
  53. 53.
    To KJ, Chan JFW, Chen H. The emergence of influenza A H7N9 in human beings 16 years after influenza A H5N1: a tale of two cities. Lancet Infect Dis. 2013;13:809–21.CrossRefPubMedGoogle Scholar
  54. 54.
    Singh N, Pandev A, Mittal SK. Avian influenza pandemic preparedness developing prepandemic and pandemic vaccines against a moving target. Expert Rev Mol Med. 2010;12:e14.CrossRefPubMedCentralPubMedGoogle Scholar
  55. 55.
    Leroux-Roels I, Borkowski A, Vanwollegham T, et al. Antigen sparing and cross-reactivity immunity with an adjuvanted rH5N1 prototype pandemic influenza vaccine: a randomised controlled trial. Lancet. 2007;370(9587):580–9.CrossRefPubMedGoogle Scholar
  56. 56.
    Waddington CS, Walker WT, Oeser C, Waddington CS, Walker WT, Oeser C, et al. Safety and immunogenicity of AS03B adjuvanted split virion versus non-adjuvanted whole virion versus whole virion H1N1 influenza vaccine in UK children aged 6 months–12 years: open label, randomised, parallel group, multicentre study. BMJ. 2010;340:c2649.CrossRefPubMedCentralPubMedGoogle Scholar
  57. 57.
    Miller E, Andrews N, Stellitano L, et al. Risk of narcolepsy in children and young people receiving AS03 adjuvanted pandemic A/H1N1 2009 influenza vaccine: retrospective analysis. BMJ. 2013;346:f794.CrossRefPubMedGoogle Scholar
  58. 58.
    Yanni EA, Marano N, Han P, et al. Knowledge, attitudes, and practices of US travelers to Asia regarding seasonal influenza and H5N1 avian influenza prevention measures. J Travel Med. 2010;17(6):374–81.CrossRefPubMedGoogle Scholar
  59. 59.
    Voeten HA, de Zwart O, Veldhuijzen IK, et al. Sources of information and health beliefs related to SARS and avian influenza among Chinese communities in the United Kingdom and The Netherlands, compared to the general population in these countries. Int J Behav Med. 2009;16(1):49–57.CrossRefPubMedGoogle Scholar
  60. 60.
    H10N8 case list 2013/2014. http://www.flutrackers.com/forum/showthread.php?t=217477. Accessed 28 July 2014.

Copyright information

© Springer Science+Business Media New York 2014

Authors and Affiliations

  1. 1.Department of Infectious Disease, Institute of Infectious Disease and EpidemiologyTan Tock Seng HospitalSingaporeSingapore
  2. 2.Department Infectious Diseases and MicrobiologyOxford University Hospital TrustOxfordUK
  3. 3.Lee Kong Chian School of MedicineNanyang Technological UniversitySingaporeSingapore

Personalised recommendations