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Ed Jewett
02-26-2010, 03:52 AM
Virulent Bird-Human Flu Hybrid Made in Lab



By Brandon Keim (http://www.wired.com/wiredscience/author/brandon9keim/) http://www.wired.com/wiredscience/wp-content/themes/wired/images/envelope.gif (brandon@earthlab.net)
February 23, 2010 |
4:38 pm |
Categories: Health (http://www.wired.com/wiredscience/category/health/)



http://www.wired.com/images_blogs/wiredscience/2010/02/feeding_birds.jpg (http://www.wired.com/images_blogs/wiredscience/2010/02/feeding_birds.jpg)
Engineered hybrids of bird and human flu strains have proven virulent in mice, raising the disturbing possibility that a natural recombination could be deadly to humans.
For years, researchers have worried that H5N1 avian influenza would mix with human flu viruses, evolving into a form that keeps its current lethality but is far more contagious. That hasn’t happened — but the latest findings, published Feb. 22 in the Proceedings of the National Academy of Sciences, show how easily it might.
“Fortunately, the H5N1 viruses still lack the ability to transmit efficiently among humans.” However, this obstacle may be overcome by mixing with flu strains common in people, wrote researchers led by University of Wisconsin virologist Yoshihiro Kawaoka. “The next pandemic then will be inevitable.”

Current strains of H5N1 have infected 478 people since 2003, and killed 286 of them. It’s difficult to transmit in humans, requiring close contact with an infected person or animal. In birds, however, H5N1 is far more contagious, and his killed tens of millions of fowl. Cases have been concentrated in Africa and Eurasia, but as the swine flu pandemic demonstrated, any flu contagious to humans will likely go global, fast.
Influenza viruses swap genes easily, with co-infections turning animals into mobile petri dishes. In 2008, hoping to learn more about how H5N1 might evolve, researchers from the Centers for Disease Control and Prevention combined it with a common human flu strain. The hybrids proved less virulent than the original bird flu strain. Researchers wondered whether more contagious bird flu would necessarily always be less deadly in humans.
The PNAS findings suggest this may not be so. The researchers engineered all 254 possible variants of hybridization between a deadly bird flu strain found in Borneo, and a human flu virus from Tokyo. They identified three strains that, at least in mice, were both contagious and deadly.
A flu virus that kills mice won’t necessarily kill humans, but the results are suggestive. All three killer hybrid strains possessed a protein taken from the human strain. Called PB2, the protein appeared to help the virus survive in the mice’s upper respiratory tract. As of now, bird flu stays in the lower respiratory tract, where it’s less likely to be casually transmitted.
The findings come as the World Health Organization meets to decide whether the swine flu pandemic has abated (http://www.reuters.com/article/idUSWLB737620100223). Though the pandemic has not proved as lethal as originally feared, it exposed how unprepared (http://is.gd/913rS) the world is for new influenza strains.
In May, Hong Kong University virologist Yi Guan, best known for finding the animal origin of SARS (http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1563723/), was asked by Science Insider about the possibility of H5N1 and swine flu mixing (http://news.sciencemag.org/scienceinsider/2009/05/exclusive-meet.html).
“If that happens, I will retire immediately and lock myself” in a sealed laboratory, said Guan.
Photo: A person feeds northern pintail ducks and whooper swans in Northern Honshu, Japan; in spring 2008, highly pathogenic H5N1 was found there in both bird species./USGS
See Also:


Flu Pandemics May Lurk in Frozen Lakes (http://www.wired.com/wiredscience/2009/05/iceplague/)
Swine Flu: Just the Latest Chapter in a 91-Year Pandemic Era (http://www.wired.com/wiredscience/2009/06/swinefluhistory/)
Tamiflu in Rivers Could Breed Drug-Resistant Flu Strains (http://www.wired.com/wiredscience/2009/09/drug-resistant-influenza/)
Swine Flu Ancestor Born on U.S. Factory Farms (http://www.wired.com/wiredscience/2009/05/swineflufarm/)
Google Could Have Caught Swine Flu Early (http://www.wired.com/wiredscience/2009/04/google-could-have-caught-swine-flu-early/)

Citation: “Reassortment between avian H5N1 and human H3N2 in?uenza viruses creates hybrid viruses with substantial virulence.” By Chengjun Li, Masato Hatta, Chairul A. Nidom, Yukiko Muramoto, Shinji Watanabe, Gabriele Neumann, and Yoshihiro Kawaoka. Proceedings of the National Academy of Sciences, Vol. 107 No. 8, February 23, 2010.
Brandon Keim’s Twitter (http://twitter.com/9brandon) stream and reportorial outtakes (http://whalefall.tumblr.com/); Wired Science on Twitter (http://twitter.com/wiredscience). Brandon is currently working on a book about ecological tipping points (http://tippingearth.net/).



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Jan Klimkowski
02-26-2010, 06:19 PM
The PNAS findings suggest this may not be so. The researchers engineered all 254 possible variants of hybridization between a deadly bird flu strain found in Borneo, and a human flu virus from Tokyo. They identified three strains that, at least in mice, were both contagious and deadly.
A flu virus that kills mice won’t necessarily kill humans, but the results are suggestive. All three killer hybrid strains possessed a protein taken from the human strain. Called PB2, the protein appeared to help the virus survive in the mice’s upper respiratory tract. As of now, bird flu stays in the lower respiratory tract, where it’s less likely to be casually transmitted.

The scientific community would defend this as pure scientific research, and probably part of some sort of precautionary principle: better forewarned than caught by surprize.

However, that is because the scientific community operates under the fundamental principle that scientific research is ethically neutral or, if at all biased, then biased towards the good and life-saving.

In my judgement, that principle is a fiction.

Further, it is a convenient fiction, because it has enabled scientists to produce incredibly potent creations and yet escape any moral blame if their creations are used to harm humanity or the wider world.

The potential for the malign use of the 254 bird-human hybrid flu types created by the CDC far outweighs any potential benefit.

There's also this:


In May 1994 the CDC admitted to have sent several biological warfare agents to Iraq from 1984 through 1989, including Botulinum toxin, West Nile virus, Yersinia pestis and Dengue fever virus.[9]

9 "The eleventh plague: the politics of biological and chemical warfare" (p. 84-86) by Leonard A. Cole (1993)

http://en.wikipedia.org/wiki/Centers_for_Disease_Control_and_Prevention