How did swine flu get its name?

Novel H1N1: It's About the Genes You Wear

When the virus first became a public health concern in 2008, early laboratory testing yielded a surprising discovery: The virus contained some of the same genes that exist in a flu virus spread between pigs. In the frantic first days of the outbreak, the discovery of the gene overlap quickly earned the virus the name "swine flu," a piece of very bad luck for the pork industry (as well as about half a million Egyptian pigs).

Further testing found that in addition to the genes it shares with the pre-existing swine flu, this new flu strain also shares genes that are found in avian flu viruses as well as human viruses. But "swine-bird-human flu" is a mouthful, and the name "swine flu" had already been hammered into public consciousness.

In an effort to protect the pork industry from further damage, the USDA officially christened the new flu virus "novel H1N1" and made a public relations effort to promote the use of this new title when discussing or describing the flu virus. This name was derived from the identification of two protein subtypes found within the virus (The "H" -- hemagglutinin -- has 16 subtypes, and the "N" -- neuraminidase -- has nine subtypes.)

Israeli authorities changed the name for an entirely different reason. In Israel, swine flu is known as "Mexico flu," because swine isn't kosher (acceptable to eat under Jewish religious customs), apparently even for use in disease names.

If pigs had a say in the matter, they would undoubtedly request a name change, though for a reason other than the obvious. Although there are presently no known cases of pigs transmitting the new virus to humans, it may be possible for humans to transmit it to pigs.

No matter what it's called, pigs' reputations -- and pork producers' livelihoods -- are still recovering.

Want more on swine flu? See the links below to more articles.

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  • Associated Press. "Israel must call new disease Mexico Flu, as swine unkosher." Apr. 27, 2009.
  • Barker, Anne. "'Mexico flu': Israel renames outbreak to avoid offence." ABC News. Apr. 28, 2009.
  • Centers for Disease Control and Prevention. "Background Information on Influenza in Pigs." June 15, 2009.
  • Centers for Disease Control and Prevention. "Key Facts About Avian Influenza (Bird Flu) and Avian Influenza A (H5N1) Virus." May 7, 2007.
  • Centers for Disease Control and Prevention. "Novel H1N1 Flu (Swine Flu)." Aug. 14, 2009.
  • Collins, Kristin. "It's called swine flu, but don't blame the pigs." The News & Observer. Apr. 28, 2009.
  • Fox News. "USDA: Please Call It H1N1, Not Swine Flu." Apr. 28, 2009.,2933,518272,00.html
  • Naughton, Philippe. "Egyptian Christians riot after swine flu cull." The News & Observer. Apr. 29, 2009.
  • PRI. "Where did the H1N1 flu start?" May 11, 2009.
  • Pruetzel-Thomas, Max. "Humans could pass H1N1 to pigs." Animal Pharm News.July 13, 2009.
  • World Health Organization. "Pandemic (H1N1) 2009." (Aug. 17, 2009)