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Swine Flu Names Evolving Faster Than Swine Flu Itself

The Germans call it Schweinegrippe, the French talk about la Grippe A. The World Health Organization now calls it "influenza A(H1N1)," and so do government officials in many countries, but not the Dutch, who are sticking with "Mexican Flu." The Mexican ministry of health, meanwhile, often calls it simply la epidemia.

Sixteen days after the world woke up to the threat of an influenza pandemic, a Babylonian confusion has arisen about what the virus—and the pandemic, if it happens—should be called. And some virologists say WHO’s new name, A(H1N1) may be politically correct but isn’t very clear and is not going to stick.

The U.S. team that first officially reported two cases of the new virus on 21 April called it "swine influenza A (H1N1)" simply because its genes matched those of viruses previously found in pigs. WHO adopted that name as well; during a 27 April teleconference with reporters, WHO influenza expert Keiji Fukuda used the words “swine flu” 22 times, and when asked the next day by a German reporter whether that name was appropriate, Fukuda said “the virus that is identified is a swine influenza virus,” and “we do not have any plans to try to introduce any new names for this disease.”

But the protests from the pork industry, as well as the senseless slaughter of all pigs in Egypt begun on 29 April, appear to have changed the agency’s mind quickly. Since 30 April, the word "swine" has not appeared in any of WHO’s press briefings or official statements.

Calling it the "Mexican flu" would be unpalatable to Mexico, and besides, it’s not certain that the virus originated in Mexico. “We’re very aware of the potential for stigmatization,” says WHO spokesperson Dick Thompson.

Health officials in many countries now tend to avoid the porcine and Mexican connections as well. Within a few days after the first report, U.S. Department of Agriculture officials started pointing out that the new virus had never been found in pigs, says Anthony Fauci, director of the U.S. National Institute of Allergy and Infectious Diseases, and government officials started “veering away” from the term swine flu.

In the Morbidity and Mortality Weekly Report, researchers from the U.S. Centers for Disease Control and Prevention came up with several creative alternatives, including, on 29 April, "swine-origin influenza A (H1N1) virus," S-OIV for short. The same name also appears in a paper that was published online yesterday by The New England Journal of Medicine. But in the 6 May issue of MMWR, CDC coined the name "novel influenza A (H1N1) virus," this time without an acronym. “It’s clearly a name that is evolving fast,” says Derek Smith, who studies flu virus evolution at the University of Cambridge in the United Kingdom.

WHO’s new name resembles the strict conventions used to distinguish individual virus isolates in the scientific literature. In that system, A/duck/Vietnam/43/2007 (H5N1) is the 43rd A(H5N1) virus isolated in Vietnam in 2007, and it came from a duck. (The species name is sometimes left out for human isolates.) But A(H1N1) alone makes less sense, says virologist Albert Osterhaus of Erasmus Medical Center in Rotterdam, the Netherlands. One of the three subtypes that make up seasonal influenza every year is also an A(H1N1), and so is the virus that caused the 1918–19 pandemic, widely known as the "Spanish flu." “It’s unfortunate, because it creates confusion,” says Smith.

The International Committee on Taxonomy of Viruses (ICTV), the official custodian of virus names, deals only with newly discovered viruses, says Australian virologist John Mackenzie, ICTV’s vice president. It has no official opinion on what particular flu strains should be called.

Nobody is in charge of naming pandemics either. The "Spanish flu" didn’t originate in Spain; it got its name because that country, not involved in World War I, didn’t keep reports about the disease out of the press, thus creating the mistaken impression that it was very hard hit. The 1957–58 pandemic, first seen in China and caused by an H2N2 strain, came to be popularly known as the "Asian flu." The pandemic of 1968–69, an H3N2 strain, went down in history as the "Hong Kong flu," because that’s where the first known outbreak occurred.

Calling the new outbreak the "Mexican flu" fits nicely with that tradition, says Osterhaus, who believes that it will be the popular name for the pandemic no matter what public health officials say. That’s also why the Dutch Outbreak Management team, an expert group of which he is a member, continues using the term "Mexican flu," as does the Dutch government. (Their insistence has triggered a fiery letter from the Mexican embassy in The Hague.)

Thompson says there’s “ongoing discussions” at WHO about other potential names. Ideas abound: Some have suggested talking about the "North American flu" in an effort to continue the geographic tradition without singling out any country. Others have suggested the "California flu" because the two patients reported in the first MMWR report came from southern California.

Influenza vaccine expert David Fedson likes the California connotation but says he has a better idea. “I favor calling it the 'Schwarzenegger virus,' ” Fedson says. “If it leads to a terrible pandemic, we'll call it the Terminator. Then everyone will know what we're talking about.”