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  • Print publication year: 2008
  • Online publication date: December 2009

71 - Avian Influenza A (H5N1)

from Part IV - Current Topics
    • By Timothy M. Uyeki, Assistant Clinical Professor of Pediatrics, University of California, San Francisco School of Medicine, San Francisco, CA; Deputy Chief, Epidemiology and Prevention Branch, Influenza Division, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, GA
  • Edited by Rachel L. Chin, University of California, San Francisco
  • Publisher: Cambridge University Press
  • DOI: https://doi.org/10.1017/CBO9780511547454.072
  • pp 475-480

Summary

INTRODUCTION

Since 2003, the global panzootic of highly pathogenic avian influenza A (H5N1) among domestic poultry and wild birds has resulted in rare, sporadic, human H5N1 cases of severe respiratory disease with high mortality in Asia, Europe, the Middle East, and Africa. Family clusters of H5N1 cases have been documented, and though most transmission of H5N1 viruses to humans is believed to be directly from sick or dead birds, limited human-to-human transmission of H5N1 viruses has been reported. As H5N1 viruses continue to evolve, the concern for a global influenza pandemic rises.

EPIDEMIOLOGY

Highly pathogenic avian influenza A (H5N1) viruses are single-stranded negative-sense RNA viruses of the Orthomyxoviridae family, whose natural reservoir is in wild aquatic ducks and geese. Influenza A viruses are subtyped on the basis of the two major surface glycoproteins, hemagglutinin (HA), and neuraminidase (NA). Avian influenza A viruses include all 16 known HA and nine known NA subtypes.

Avian influenza is a disease of birds caused by infection with avian influenza A viruses that infect the respiratory and gastrointestinal tracts. Birds excrete avian influenza A viruses in feces, and the virus can remain viable for prolonged periods in the setting of low temperatures, low humidity, and abundant fecal protein matter. H5N1 virus infections of other animals, including pigs, cats, dogs, civet cats, a stone marten, tigers, and leopards have also been reported.

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REFERENCES
Areechokchai, D, Jiraphongsa, C, Laosiritaworn, Y, et al. Investigation of Avian Influenza (H5N1) outbreak in humans – Thailand, 2004. MMWR 2006;55(Suppl 1):3–6.
Chotpitayasunondh, T, Ungchusak, K, Hanshaoworakul, W, et al. Human disease from influenza A (H5N1), Thailand, 2004. Emerg Infect Dis 2005;11:201–9.
Jong, M D, Simmons, C P, Thanh, T T, et al. Fatal outcome of human influenza A (H5N1) is associated with high viral load and hypercytokinemia. Nat Med 2006;12:1203–7.
Dinh, P N, Long, H T, Nguyen, T K T, et al. Risk factors for human Infection with avian influenza A H5N1, Vietnam, 2004. Emerg Infect Dis 2006;12:1841–7.
Kandun, I N, Wibisono, H, Sedyaningsih, E R, et al. Clustering of human H5N1 cases in Indonesia, 2005. N Engl J Med 2006;355:2186–94. (See also correspondence in N Engl J Med 2007;356:1375–7.)
Schuneman, H J, Hill, S R, Kakad, M et al. WHO Rapid Advice Guidelines for pharmacological management of sporadic human infection with avian influenza A (H5N1) virus. Lancet Infect Dis 2007;7:21–31.
Tran, T H, Nguyen, T L, Nguyen, T D, et al. World Health Organization International Avian Influenza Investigative Team. Avian influenza A (H5N1) in 10 patients in Vietnam. N Engl J Med 2004;350:1179–88.
Ungchusak, K, Auewarakul, P, Dowell, S F, et al. Probable person-to-person transmission of avian influenza A (H5N1). N Engl J Med 2005;352:333–40.
World Health Organization (WHO). Update: WHO-confirmed human cases of avian influenza A(H5N1) infection, 25 November 2003–24 November 2006. Wkly Epidemiol Re 2007;82:41–8.
Writing Committee of the Second World Health Organization (WHO) Consultation on Clinical Aspects of Human Infection with Avian Influenza A (H5N1) Virus. Update on avian influenza A (H5N1) virus infection in humans. N Engl J Med 2008;358:261–73.
ADDITIONAL READINGS
Jong, M D, Thanh, T T, Khanh, T H, et al. Oseltamivir resistance during treatment of influenza A (H5N1) infection. N Engl J Med 2005;353:2667–72.
Subbarao, K, Luke, C. H5N1 viruses and vaccines. PLoS Pathog 2007;3:e40.
World Health Organization (WHO). WHO case definitions for human infections with influenza A(H5N1) virus. 29 August 2006. Available at: http://www.who.int/csr/disease/avian_influenza/guidelines/case_definition2006_08_29/en/print.html.
World Health Organization (WHO). Avian influenza, including influenza A (H5N1), in humans: WHO interim infection control guideline for health care facilities. 24 April 2006. Available at: http://www.wpro.who.int/NR/rdonlyres/EA6D9DF3-688D-4316-91DF-5553E7B1DBCD/0/InfectionControlAIinhumansWHOInterimGuidelinesfor2b_0628.pdf.
World Health Organization (WHO). Antigenic and genetic characteristics of H5N1 viruses and candidate H5N1 vaccine viruses developed for potential use as pre-pandemic vaccines. March 2007. Available at: http://www.who.int/csr/disease/avian_influenza/guidelines/summary H520070403.pdf.