samedi 6 juin 2009

2005: Le Center for Disease Control réalise un mix de grippe aviaire, humaine et de H1N1 pour une étude sur des pandémies qui n'existent pas encore...


CDC to mix avian, human flu viruses in pandemic study

Robert Roos * News Editor
Jan 14, 2004 (CIDRAP News) –
http://www.cidrap.umn.edu/cidrap/content/influenza/panflu/news/jan1404hybrids.html

One of the worst fears of infectious disease experts is that the H5N1 avian influenza virus now circulating in parts of Asia will combine with a human-adapted flu virus to create a deadly new flu virus that could spread around the world.

That could happen, scientists predict, if someone who is already infected with an ordinary flu virus contracts the avian virus at the same time. The avian virus has already caused at least 48 confirmed human illness cases in Asia, of which 35 have been fatal. The virus has shown little ability to spread from person to person, but the fear is that a hybrid could combine the killing power of the avian virus with the transmissibility of human flu viruses.

Now, rather than waiting to see if nature spawns such a hybrid, US scientists are planning to try to breed one themselves—in the name of preparedness.

The Centers for Disease Control and Prevention (CDC) will soon launch experiments designed to combine the H5N1 virus and human flu viruses and then see how the resulting hybrids affect animals. The goal is to assess the chances that such a "reassortant" virus will emerge and how dangerous it might be.

CDC officials confirmed the plans for the research as described recently in media reports, particularly in a Canadian Press (CP) story.

Two ways to make hybrids
The plans call for trying two methods to create hybrid viruses, CDC spokesman David Daigle told CIDRAP News via e-mail. One is to infect cells in a laboratory tissue culture with H5N1 and human flu viruses at the same time and then watch to see if they mix. For the human virus, investigators will use A (H3N2), the strain that has caused most human flu cases in recent years, according to the CP report.

The other method is reverse genetics—assembling a new virus with sets of genes from the H5N1 and H3N2 viruses. Reverse genetics has already been used to create H5N1 candidate vaccines in several laboratories, according to Daigle. The National Institutes of Health (NIH) said recently it would soon launch a clinical trial of one of those vaccines.

Of the two methods, the co-infection approach was described as slower and more laborious, though closer to what happens in nature.

Any viable viruses that emerge from these processes will be seeded into animals that are considered good models for testing how flu viruses behave in humans, according to Daigle. The aim will be to observe whether the animals get sick and whether infected animals can infect others.

The World Health Organization (WHO) has been "pleading" for laboratories to do this research, because it could provide some evidence to back up the agency's warnings about the risk of a flu pandemic, according to the CP report.

Klaus Stohr, head of the WHO's global influenza program, was quoted as saying that if none of the hybrids caused disease, the agency might be inclined to dial down its level of concern. But if the experiments produce highly transmissible and pathogenic viruses, the agency will be more worried, he said.

Safety precautions
Because of the obvious risks in creating viruses with the potential to spark a pandemic, the work will be done in a biosafety level 3 (BSL-3) laboratory at the CDC in Atlanta, Daigle told CIDRAP News.

"We recognize that there is concern by some over this type of work. This concern may be heightened by reports of recent lab exposures in other lab facilities," he said. "But CDC has an incredible record in lab safety and is taking very strict precautions."

Daigle said the US Department of Agriculture requires that highly pathogenic avian influenza (HPAI) viruses be treated as "Select Agents" and that research on them must be done in BSL-3 labs with "enhancements." These include "special provisions to protect both laboratory workers and the environment."

BSL-3 is the second highest level of laboratory biosecurity. It is used for work with pathogens that may cause serious or potentially lethal disease if inhaled, such as tuberculosis or St. Louis encephalitis, according to the CDC.

CDC experiments with HPAI viruses have to pass reviews by the agency's Institutional Biosafety Committee and Animal Care and Use Committee, Daigle said. The facilities involved are inspected by the USDA and the CDC's Office of Safety and Health, and staff members who work with Select Agents require special clearance.

It's been done before
The upcoming experiments will not break entirely new ground for the CDC, the CP story revealed. The agency already has made hybrid viruses with H5N1 samples isolated from patients in Hong Kong in 1997, when the virus first caused human disease.

The results of that research have not yet been published, and the CDC has said little about them. In the CP report, Dr. Nancy Cox, head of the CDC's influenza branch, commented only, "Some gene combinations could be produced and others could not."

Daigle added little to that. He said, "The reassortment work with the 1997 isolate was intermittently interrupted with SARS [severe acute respiratory syndrome] and then the 2004 H5N1 outbreak. We are currently concentrating our efforts on understanding the pathogenicity of the 2004 strains (non-reassortants) in mammalian models."

He said the CDC hopes to prepare a report on that research "in the near future."


CDC to conduct avian flu pandemic experiments

Updated Mon. Dec. 27 2004 5:15 PM ET

Canadian Press, http://www.ctv.ca/servlet/ArticleNews/story/CTVNews/1104186283991_7/?hub=Health

TORONTO -- The alarm now sounds with increasing frequency and urgency: the world could be on the brink of an influenza pandemic sparked by the highly virulent avian flu strain ravaging poultry stocks in Southeast Asia, experts fear.

But can that strain -- known as H5N1 -- actually acquire the ability to spread easily to and among people? And if it can, how likely is that dreaded event to occur?

Early in the new year, U.S. scientists will begin experiments that should provide some answers to those questions. In the process, they hope to learn more about why a virus that nature designed to infect migratory water birds has the astonishing capacity to kill mammal species ranging from house cats to tigers to humans.

The work won't indicate how soon a pandemic might start. And the findings can't be taken as a guarantee the virus will evolve as the science predicts.

"Like a lot of science, it's an imitation of nature,'' explains Dr. Frank Plummer, scientific director of Canada's National Microbiology Laboratory.

"It doesn't replicate exactly what happens. But I think it gives you an idea of the propensity of the H5N1 virus to do this thing.''

The researchers, from the influenza branch of the Centers for Disease Control in Atlanta, will mate H5N1 and human flu viruses in a process known as reassortment. Viable offspring will be tested in animals thought to be good surrogates for humans, to see if the viruses can infect, can be transmitted easily from infected animals to healthy ones and to note the severity of disease each provokes.

In other words, the CDC researchers will be deliberately engineering viruses of pandemic potential. It's high-risk but crucial work, the influenza community insists.

"It's a dangerous experiment,'' admits Dr. Robert Webster, a world-renowned expert on influenza based at St. Jude Children's Research Hospital in Memphis, Tenn.

Still, Webster has no doubt the work needs doing. Science must gain a better understanding of the menacing H5N1 virus.

"These experiments are fully justified, knowing what we know,'' he stresses, using a scatological adjective to describe how scared influenza experts are of H5N1.

"This is the worst virus I've ever met in my long career.''

The World Health Organization has been pleading for months for qualified research facilities -- of which there are few -- to undertake this work.

The Geneva-based agency would like to be able to put some kind of odds on how likely H5N1 is to become a pandemic strain and how deadly -- or not -- H5N1 reassortment viruses might be in humans.

If none of the hybrids cause severe disease, the organization might feel comfortable with stepping down its current high level of alert, explains Dr. Klaus Stohr, director of the WHO's global influenza program.

On the other hand, if CDC researchers easily produce highly transmissible and lethal hybrids, "that would certainly add to our concern.''

It's about quantifying risk.

"Currently we do risk-speculation, but we want to do risk-assessment. And that will give us scientific evidence on the possible outcome on the emergence of a pandemic virus,'' Stohr says.

"It will give us an opportunity to predict the probability because we will have an understanding on the number of reassortment viruses which are viable, the percentage of those that are viable which are then transmissible -- and also on the percentage of those which are viable, transmissible and pathogenic. And how pathogenic they are.''

The CDC researchers will work in high containment level 3-enhanced labs, says Dr. Nancy Cox, the leading influenza authority who heads the agency's flu branch. The labs have special features designed to protect both the health of the workers and the world against a viral escape.

"It's not typical level 3,'' Cox says, adding the lab workers are "extremely cognizant of the danger of the H5 viruses.''

"And of course we know we can autoclave these viruses,'' she adds, referring to a process that kills using high pressure and heat. "So if you find something that is particularly worrisome, you can get rid of it.''

Still, lab accidents happen. Since SARS was contained in mid-2003, four lab workers in Asia have infected themselves with the potentially deadly disease and one spread it beyond the walls of the laboratory. Earlier this year, a Russian lab worker died after accidentally infecting herself with Ebola virus.

Given that reality, some groups have raised concern that work like this should not be done. But a top virologist from the Netherlands insists it must be, expressing confidence in the CDC's ability to do the job safely.

"If it's being done by CDC, then the good thing about that is that safety measures will properly be in place,'' said Dr. Albert Osterhaus, of the Erasmus Medical Centre in Rotterdam.

The CDC researchers will mix genes from H5N1 with genes from circulating strains of human flu to see which combinations produce viruses that grow and infect. Cox says H3N2 -- the strain that has been responsible for most human flu in recent years -- will be the first priority.

However, Southeast Asia has recently seen activity with H1N1, the mild modern descendant of the strain that caused the Spanish flu of 1918. So the CDC has been sequencing H1N1 viruses recently isolated in Thailand to be able to work with it as well.

"We're really keeping our minds open. But as long as H3N2 viruses continue to predominate, that will be our first target,'' Cox says.

Reassortment studies can be performed two ways, she explains. Scientists can use reverse genetics, a procedure that allows them to custom tailor a virus with a predetermined constellation of genes from each parent virus.

The other alternative is what Cox describes as the classical way -- simultaneously infecting tissue culture with H5N1 and H3N2 viruses and seeing what results. That approach is more time-consuming and laborious, but more closely mimics evolution of influenza viruses in nature.

"We will probably be using a combination of the two different methods. I think there are advantages and disadvantages to each,'' says Cox, who believes her team may have some preliminary results within a couple of months of beginning the work.

Some skeptics have pointed to the fact H5N1 hasn't yet reassorted to argue it may not be able to do so outside of the artificial confines of a laboratory.

Webster thinks that optimism is misplaced. He calls H5N1 "one of the most promiscuous viruses that we've ever seen. It would amaze me if it wouldn't mate with a human virus, given the opportunity.''

CDC researchers have already made hybrid viruses with H5N1, using versions of the virus isolated after it first caused human infections in 1997 in Hong Kong.

"Some gene combinations could be produced and others were not,'' is all Cox will reveal of that as-yet unpublished work.

Even if, in this new round of experiments, CDC's researchers fail to produce a single viable hybrid virus, that doesn't prove H5N1 won't reassort in nature, experts say.

For one thing, flu viruses are constantly evolving. The viruses that the CDC will work with now -- isolated in 2004 -- are not identical to those from the 1997 outbreak. A combination that fails with the 1997 virus might work with a 2004 virus -- or a 2005 version.

"Things in nature can happen that you can't replicate in the lab necessarily,'' stresses Plummer, whose lab is working on producing reassortments of H7N3, the strain behind last spring's avian flu outbreak in British Columbia.

"Can you be sure that all possible virus reassortments have occurred? No. And fairly minor changes in viruses can make really huge differences in their biologic properties.''


Swine Flu Smoking Gun? CDC was Combining Flu Viruses in 2004
Wednesday, April 29, 2009 by: Sherry Baker, Health Sciences Editor, http://www.naturalnews.com/026159.html
(NaturalNews) Last week, when what is now called a "swine flu" was first reported to be infecting and killing some people in Mexico, health officials noted it was a strain of flu never before seen. In fact, it is technically incorrect to call this simply a "swine" flu. Analyses showed it's a mixture of swine, human and avian viruses, according to the Centers for Disease Control (CDC). Moreover, it is genetically different from the fully human H1N1 seasonal influenza virus that has been circulating globally for the past few years. Bottom line: the new flu virus contains DNA from avian, swine viruses (including elements from European and Asian viruses) and human viruses.

So did this curious mixture just develop naturally, out of the blue? Is it the result of inhumane farming practices, as the Humane Society of the United States (http://www.hsus.org/) has suggested, that exposes immune-compromised pigs to all sorts of animal and human feces?

Well, maybe. But let's go back and look at the facts to see if any other scenario could be possible.

First of all, there's the troublesome detail that the virus has elements that come from multiple continents. Then there's the fact that true swine flu is only rarely transmissible to humans -- this flu is spreading human-to-human, most likely because it contains DNA from human flu.

Could someone have deliberately mixed these viruses together? Is that possible? Absolutely.

Was this virus mixing being done artificially in the lab, or had it already been done? Yes.

Who was blending potentially swine, human and/or avian viruses in labs? Were those horrible generic boogie men known to Americans far and wide as "terrorists" doing it? There's no proof of bioterrorism at work here yet. However, there is evidence the United States government has been working on concocting new flu virus blends.

So could the hysteria-provoking, new swine flu have escaped from a lab? Or was it deliberately released as some kind of test? When these kinds of questions are asked, the knee-jerk reaction of the mainstream media (MSM) is to giggle and talk about "conspiracy theories" and to joke about wearing tinfoil hats.

But here's the potential smoking gun, the facts that suggest a potential source of the pandemic could be CDC labs. And at the very least, this possibility deserves thoughtful examination and research.

The University of Minnesota Center for Infectious Disease Research and Policy (CIDRAP) is hardly a place most Americans have heard about and, apparently, the Center's web site has news the MSM isn't familiar with, either. But information they published years ago has now taken on an urgent importance. CIDRAP, along with the Canadian newspaper Canadian Press (CP), revealed back in 2004 that the CDC was launching experiments designed to mix the H5N1 (avian) virus and human flu viruses. The goal was to find out how likely it was such a "reassortant" virus would emerge and just how dangerous it might be. Of course, it's logical to wonder if they also worked with the addition of a swine flu virus, too.

Here's some background from the five-year-old report by the University of Minnesota research center: "One of the worst fears of infectious disease experts is that the H5N1 avian influenza virus now circulating in parts of Asia will combine with a human-adapted flu virus to create a deadly new flu virus that could spread around the world. That could happen, scientists predict, if someone who is already infected with an ordinary flu virus contracts the avian virus at the same time. The avian virus has already caused at least 48 confirmed human illness cases in Asia, of which 35 have been fatal. The virus has shown little ability to spread from person to person, but the fear is that a hybrid could combine the killing power of the avian virus with the transmissibility of human flu viruses. Now, rather than waiting to see if nature spawns such a hybrid, US scientists are planning to try to breed one themselves -- in the name of preparedness."

And CDC officials actually confirmed the government had plans for the research. The CIDRAP News folks did a great job covering this important issue, which was apparently mostly ignored by the MSM back in 2004, and CIDRAP News wrote to the CDC for information. This e-mail produced an answer from CDC spokesman David Daigle who admitted the CDC was working on the project in two ways. "One is to infect cells in a laboratory tissue culture with H5N1 and human flu viruses at the same time and then watch to see if they mix. For the human virus, investigators will use A (H3N2), the strain that has caused most human flu cases in recent years," the CIDRAP story stated. This co-infection approach was described as slow and labor-intensive. However, it was a way to produce a new virus that appeared to be closer to what develops in nature.

There was another, faster way CDC scientists could create the mix, too. Called reverse genetics, it involves piecing together a new virus with genes from the H5N1 and H3N2 viruses. Reverse genetics had already been used successfully to create H5N1 candidate vaccines in several laboratories, the CDC's Daigle wrote. "Any viable viruses that emerge from these processes will be seeded into animals that are considered good models for testing how flu viruses behave in humans... The aim will be to observe whether the animals get sick and whether infected animals can infect others," he revealed in his e-mail.

What's more, the CP reported the CDC had already made hybrid viruses with H5N1 samples isolated from patients in Hong Kong in 1997, when there was the first outbreak of that virus, dubbed the "Hong Kong flu". It is not clear if the results of that research were ever published. Back in 2004, Dr. Nancy Cox, then head of the CDC's influenza branch, would tell the CP only: "Some gene combinations could be produced and others could not."

The CP's report noted that the World Health Organization (WHO) had been "pleading" for laboratories to do this blending-of-viruses research. The reason? If successful, these flu mixes would back up WHO's warnings about the possibility of a flu pandemic. In fact, Klaus Stohr, head of the WHO's global flu program at the time, told the CP that if the experiments were successful in producing highly transmissible and pathogenic viruses, the agency would be even more worried -- but if labs couldn't create these mixed flu viruses, then the agency might have to ratchet down its level of concern.

The 2004 CIDRAP News report addressed the obvious risks of manufacturing viruses in labs that, if released, could potentially spark a pandemic. However, the CDC's Daigle assured the Minnesota research group the virus melding would be done in a biosafety level 3 (BSL-3) laboratory. "We recognize that there is concern by some over this type of work. This concern may be heightened by reports of recent lab exposures in other lab facilities," he told CIDRAP. "But CDC has an incredible record in lab safety and is taking very strict precautions."

Five years later, we must ask more questions. Were those safety measures enough? Was the CDC creating or testing any of these virus mixes in or near Mexico? What other potentially deadly virus combinations has the US government created? Don't US citizens, as taxpayers who funded these experiments, have a right to know? And for all the residents of planet earth faced with a potentially deadly global epidemic, isn't it time for the truth?

For more information:
"New flu is a genetic mix", http://www.reuters.com/article/dome...

"CDC to mix avian, flu viruses", http://www.cidrap.umn.edu/cidrap/co...

"CDC to conduct avian flu pandemic experiements", http://www.ctv.ca/servlet/ArticleNe...

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