Posted on 08/01/2006 2:24:02 PM PDT by blam
Bird flu mixed with human flu lacks punch
18:04 01 August 2006 NewScientist.com news service
Peter Aldhous
Combining genes from the deadly H5N1 bird flu virus with those from a common human flu virus does not seem to create strains with instant pandemic potential, researchers have found.
H5N1 meets two of three requirements for a pandemic strain: it is highly pathogenic and unfamiliar to most people’s immune systems. If it also acquired the ability to transmit easily from person to person, H5N1 would threaten millions of lives. One way this could happen is if the virus swapped genes with human flu.
A team at the US Centers for Disease Control (CDC) in Atlanta, Georgia, engineered flu viruses that contained genes for the external “coat” proteins of H5N1 and the internal proteins of H3N2, the most common variety of human flu in circulation.
They then inoculated ferrets with these “reassortant” viruses. When ferrets are in adjacent cages, H3N2 passes readily from one cage to the next. But neither H5N1, nor the new viruses, could be transmitted in this way, and the engineered strains were much less pathogenic than H5N1.
This suggests it may take more than a simple exchange of genes to turn H5N1 into a global killer, although the team has yet to explore other possible reassortants.
Mutation not recombination
However, the virus that caused the 1918 pandemic, which killed more than 40 million people, probably evolved by the mutation of a bird flu strain rather than recombination with a human virus.
(Excerpt) Read more at newscientist.com ...
Ping.
You mean... we're not "Doomed"? What a gyp!
The pandemic that never was.
Just wait until some of that combined flu mysteriously wanders out of the lab.
Similar mishaps in the past have resulted in Milla Jovovich running around skimpy shorts.
Hey! Don't mix those two - this isn't a Reese's Peanut Butter Cup commercial!
Whatever they mixed up, it isn't what is killing things out there.
As to whether H5N1 will become the next pandemic human flu, I can't say, but I would not decide offhand that something could not exist because scientists have been unable to create it.
Afaik, they have not made a mosquito, either--and those little bloodsuckers are a real nuisance here.
Ping for the latest.
"As to whether H5N1 will become the next pandemic human flu, I can't say,"
Hence my statement "The pandemic that never was".
Combining genes from the deadly H5N1 bird flu virus with those from a common human flu virus does not seem to create strains with instant pandemic potential, researchers have found.
and
This suggests it may take more than a simple exchange of genes to turn H5N1 into a global killer, although the team has yet to explore other possible reassortants.
The Bottom line: ...a vaccine may not protect against the virus as it mutates and evolves. “We are far from out of the woods with H5N1,” says CDC director Julie Gerberding.
If you don't RTFA, you get nice, safe, warm fuzzies. It ain't over 'till it's over. I hope it never develops into a pandemic, but hope alone is no reason to let your guard down.
Good news. Thanks for the update.
Let's move along to asteroids and magnetic pole reversal. I tell you, Karl Rove has a buncha cards up his sleeve.
I sure hope you stay right. This is a nasty bug--and kills about half those infected.
That's why I take my flu straight up.
WTH would anyone want to try to create a crossbred virus? To see if they can create a super virus with the potential to wipe out civilization? How stupid and egotistical can they get?
Ping for Niman's take on all this:
http://www.recombinomics.com/whats_new.html
Virus moving via recombination.
From Niman's site:
H5N1 has been evolving via recombination. The changes are small but frequent. Currently, there are at least four different versions of H5N1 bird flu circulating. Clade 1 has caused reported human fatalities in Vietnam, Thailand, and Cambodia. For clade 2, there are at least three distinct versions. One is in Indonesia. Most of the human cases in Indonesia have a novel HA cleavage site that has not been reported in any avian isolate. In the current paper discussed above, the Indonesia/5/05 isolate was detected in respiratory secretions of infected ferrets. A second clade 2 version is the Fujian strain, which is represented in all public human isolates from China in 2005 and 2006. Thus strain has also been detected in birds in Laos and Malaysia. The third clade 2 strain is the Qinghai strain, that is being transported and transmitted worldwide by migratory birds. There are multiple versions of this strain, but it has cause human fatalities in Turkey, Azerbaijan, and Egypt and has also caused a human infection in Djibouti.
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My take on this: the scientists have tried to mix one strain with another strain in ferrets. Nature has the opportunity to try recombination millions of times. Frankly, I'd put my money on Nature.
Just my opinion.
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