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Treatment and prevention of avian influenza

Iain Stephenson, MD, FRCP
Section Editor
Martin S Hirsch, MD
Deputy Editor
Anna R Thorner, MD


There have been five influenza pandemics during the past 100 years, and each has been caused by the emergence of a novel virus. In the 1957 and 1968 pandemics, the new viruses contained components of previous human as well as avian influenza viruses. The origin of the influenza virus responsible for the 1918 pandemic, which killed more people in a single year than the bubonic plague, remains uncertain, but it appears to have been an adapted avian influenza strain. The emergence of a novel H1N1 human-swine-avian reassortant virus in 2009 in North America started a new pandemic. (See "Epidemiology of pandemic H1N1 influenza ('swine influenza')".)

Sporadic transmission of avian influenza H5N1 to more than 840 humans since 2003 has prompted concerns that conditions are suitable for emergence of the next pandemic; the case-fatality rate is approximately 53 percent [1]. However, seroprevalence studies have found that some exposed individuals may have had a subclinical or mild infection, suggesting that the reported case-fatality rate may be an overestimate.

The treatment and prevention of H5N1 avian influenza will be reviewed here. The possible role of avian influenza vaccines, and the epidemiology, transmission, pathogenesis, clinical manifestations, and diagnosis of avian influenza are discussed separately. (See "Avian influenza vaccines" and "Epidemiology, transmission, and pathogenesis of avian influenza" and "Clinical manifestations and diagnosis of avian influenza".)

The novel avian influenza A H7N9 virus that emerged in 2013 in China is also presented separately. (See "Avian influenza A H7N9: Epidemiology, clinical manifestations, and diagnosis".)


Two classes of drugs are effective against influenza: adamantanes (amantadine and rimantadine, also known as M2 ion channel inhibitors) and neuraminidase inhibitors (oseltamivir and zanamivir). H5N1 viruses isolated in Thailand and Vietnam have amino acid substitutions within the M2 protein that confer resistance to amantadine and rimantadine [2,3]. However, these viruses are susceptible to the neuraminidase inhibitors [4].


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Literature review current through: Sep 2016. | This topic last updated: Dec 11, 2015.
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