There were 3 flu pandemics in the 20th century and each has gotten an unofficial name. 1918 was the Spanish flu, so named because the Spanish were the only ones honest enough to acknowledge its presence initially and thus got stuck with the blame. Like the other two pandemic viruses it probably originated in southern China (although its history is cloudy), so the nicknames of the 1957 (Asian flu) and 1968 (Hong Kong flu) are probably more apt, or at least less inapt. Now we have swine flu. Excuse me. I mean influenza A/H1N1, since that is how WHO is calling it so as not to impugn the good name of pigs:
To quell the notion that pigs are to blame for the swine influenza H1N1 epidemic, three international agencies said today they would take the “swine” out of the virus’s name and call it “influenza A/H1N1″ instead.
The United Nations Food and Agriculture Organization (FAO) said today it has agreed with the World Health Organization (WHO) and the World Organization for Animal Health (OIE) “to no longer refer to ‘swine flu’ but instead to ‘influenza A/H1N1.’”
Joseph Domenech, the FAO’s chief veterinary officer, said in the FAO statement that there is no evidence that the new virus is circulating in pigs in Mexico or anywhere else and that pork consumption poses no increased risk of contracting the virus.
The move comes in the wake of reports that Egypt began slaughtering pigs yesterday out of the mistaken concern that they could spread the new virus to people. Some countries have banned pork from Mexico and the United States for the same reason. (Robert Roos, CIDRAP News)
We’ve seen the name blame game before. I suppose it’s understandable, but influenza A/H1N1 is a very bad alternative since it’s also the broad designation for the seasonal influenza subtype that’s been co-circulating with H3N2 since 1977. But each isolate of this virus also has an “official” name or designation. One isolated from a Texas case has this name: A/Texas/05/2009(H1N1). The naming system looks complicated but it’s really quite simple. The A-part means that this is a flu virus of type A (rather than flu B or flu C). Texas is a location marker, which could be broad, like Texas, or more narrow, like the name of a city (e.g., Hong Kong). The 05 is the specimen identifier in the lab where it was isolated and 2009 is the year. If the virus had been isolated from a non-human animal, that would be included, e.g., A/Chicken/Shantou/4231/2003. And the H1N1 part is the subtype.
Influenza subtypes are very broad classifications based on the immunologic reactions of the two most prominent proteins on the virus particle’s surface (hemagglutinin, HA; neuriminidase, NA). There are 16 broad HA subtypes, numbered 1 to 16; and similarly for the 9 NA subtypes. But the H1N1 we have been experiencing as one of the seasonal flu subtypes and the H1N1 subtype of this outbreak are quite different (that’s part of the problem). When those differences are within viruses infecting the same species, like the continually shifting H1N1 human variants that appear annually, we call them strains. But the current H1N1 has 8 gene segments characteristic of swine (even though some of the segments have bird or human ancestry; see this post), so calling it swine flu doesn’t seem inappropriate.
Call me politically incorrect.