Posted on 05/09/2005 10:18:08 AM PDT by Dog Gone
If you create a vaccine based on the antigenic characteristics of H5N1 then you have a viable vaccine. Antigenic shift or drift will not diminish the efficacy of the vaccine. the vaccine give the immune system a "head start"....
She seems to think the new vaccine will work, even if the virus has changed.
Is there a difference of opinion here?
Daily Bird Flu News Updates:
The Scotsman - 8th August 2005
Optimism over new avian flu vaccine
US - The US government is optimistic about a new vaccine to protect against an outbreak of potentially deadly avian flu, and distribution could start as soon as mid-September, a senior federal health official said. The government is ready to move ahead with ordering significantly more than the two million doses it acquired from French vaccine maker Sanofi-Pasteur before testing began earlier this year to jump-start the US vaccine stockpile in case the tests were successful, said Dr. Anthony S. Fauci.
Text of the post:
There was a prospective study done which showed that N-acetyl cysteine or NAC prevented people exposed to an H1N1 flu bug from getting sick, even though they later possessed antibodies to this bug. (The H1N1 strain in question was just the common flu bug that year.) In other words, the NAC users apparently fought off the virus without becoming ill. Only 25% of those with antibodies to the H1N1 bug, and who were in the NAC group, had had flu symptoms. In the placebo group, if you looked at people with H1N1 antibodies, 79% had been ill. The participants in the NAC group took 600mg twice daily.
I think NAC changes certain amino acid levels in some way which helps the immune system fight off viruses, but I don't think it acts directly on T-cell or other immune cell signals (cytokines). I can't be sure, though.
I buy my stuff from vitacost.com, it's about $13 for 120 600mg capsules of NAC. For my family (me, husband, and 2 kids) that's 20 days' worth of preventive use. Someone over on flu clinic pointed out that long-term use may diminish copper and zinc absorption, so supplementing with these if you use NAC for long periods would be a good idea.
This is the link to the study the poster mentioned:
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=9230243&dopt=Citation
Hey, it sold Sunday newspapers in New York, and that's all that really matters with the news.
If Strep Suis 2 transmitted from pigs to humans is really the cause of these deaths (not just a story invented to cover up a major H5N1 outbreak), then this part of China is facing at least two MAJOR health problems at the same time (H5N1 being the other).
Kelly, what is your take on the commentary in post 1291?
I doubt China has 50,000 "health care workers" they could send somewhere to control an outbreak.
They have a lot soldiers, though...
You're right, but, I still don't really trust info coming out of China. *Sigh* Will we ever know what is really going on over there?
NAC-NAC. Thanks for that post! Had never heard of that.
FULL STUDY: http://erj.ersjournals.com/cgi/reprint/10/7/1535
(SHOULD START AUTO-DOWNLOAD OF PDF FILE)
You're welcome BearWash. I hadn't heard of it either. I'll get it posted to the preparedness thread in a few minutes.
Influenza is an inherently unstable RNA virus despite this fact specific and cross beneficial vaccinations offer as much as 34% and 70% efficacy respectively. A (H5N1) is not the only vaccine produced to combat influenza, there are several other strains and variants infecting the population yearly. The only difference with H5N1 is it's virulence and high mortality statistic. The fact that influenza virus undergo recombination and reassortment events DOES lower the efficacy of any given vaccination but not below viability statistics quoted previously.
H5N1 is zoonotic, this is the normal etiological lifecycle of an avian strain please bear in mind that H5N1 is an AVIAN strain all avian type A influenza strains must first undergo a reassortment event most likely with a porcine o human B or C type influenza variant. At a molecular level where molecular transactions determine zoonotic compatibility the human species lacks among many things the sialyllactose receptors required for attachment of the viruses to epithelial cells. The porcine hosts acts as an "optimizer" for the virus to acquire the genetic and antigenic specificity that is required to infect a human host. If this occurs then you have an efficient human to human transmission mechanism (biological)
This is as basic as I can make the description the molecular transaction are HUGELY complex.
"Otherwise, it could be a really rough ride."
It's a ticking bomb, the calm before the storm, this period is known as the "herald wave" and does not mean that we are safe even now.
I make it 4 :
Possible VHF outbreak (Ebola or Marburg)
Confirmed (CDC and WHO)S.suis serotype 2
Influenza Type A H5N1
Unknown outbreak of suspected recombinant influenza / VHF presenting clinical symptoms consistent with both diseases
yes you do :-)
"But, there would seem to be a difference of opinion with what Dr. Niman states."
I disagree strongly with what he said. Within the course of the flu season influenza will change drastically I cannot emphasize this enough. Influenza is inherently unstable because of the type of RNA virus that it is. For this reason the genome is DYNAMIC not static. Efficacy will diminish but within understandable thresholds. There are some rare occurrences that result in events where shift or drift creates variants that have no cross immune benefit from existing vaccine stocks. THIS IS RARE and happens with non virulent and highly virulent variants in some flu seasons historically. I am assuming that Dr. Niman's comments where taken out of context or caveats and qualifiers where stripped out of his statements by an ignorant journalist. Otherwise his comments are prejudging an unknowable situation in the future. In every year there emerge avian strains that have the potential for pandemic not every year obviously do we see such a pandemic. The variant may never gain the genetic factors to effect efficient human to human biological transmission mechanisms. When they do gain this factor we see pandemic, ONLY then can the genome and antigentic characteristics of the variants be matched to an existing vaccination stock. rarely is there a requirement to create a NEW vaccine. I am not saying this could not happen just that Dr Niman does not know this either. And the chances that the existing vaccine will provide cross immune benefit are higher than they will not.
Thanks for clearing up that question.
I'll take a 34-70% benefit over "none" any day. But with a nasty virus like this, even that might not be enough for a lot of people if this virus gets a widespread breakout. It's current lethality in all known human cases seems to have only the choices of "deadly" and "deadlier".
What seems particularly worrisome - among a cast of some awful choices - is the combination VHF/Flu virus (your 4th possibility).
That's OK honey :-) Everyone does the same when it comes to their own domain of expertise, that's what is so great about Free Republic. I have been helped here by many more knowledgeable folks in the area of politics and economics :-)
"What seems particularly worrisome - among a cast of some awful choices - is the combination VHF/Flu virus (your 4th possibility)."
Yes there seems to be some observable evidence of this, as yet the laboratory results are pending. I hope this proves to be inaccurate but it has been postulated by Boxun among others and so far no response or rebuttal form the WHO or Chinese Health Ministry. Yet the evidence was lying dead on the shores of lakes and rivers for all the field teams to see. Ebola or Marburg are also confirmed outbreaks again as yet there is no information in the public domain.
A recombination event looks likely and if you want to know why 50,000 Chinese workers and military are doing in the area that's what the smart money is on option #4 above.
At some point we may know what WAS going on there but it will be a bit late to do anything effective in response.
Thanks (as usual)!
I'm aware, at an educated layman's level anyway, of the usual course of a flu outbreak. When I asked if something about H5N1 makes it fundamentally difficult to spread from human to human I should have been more specific.
The question really boils down to:
1. Do we have any way of estimating how long is it likely to be until the necessary reassortment occurs?
2. Is there anything about H5N1 that might make it more difficult for this specific virus to make that change? (A bit of wishful thinking, perhaps.)
"1. Do we have any way of estimating how long is it likely to be until the necessary reassortment occurs?
That would not be possible as this is purely a random event based on convergence opportunity and mutability.
In most cases there exists a virulent avian strain that NEVER achieves efficient human to human transmission.
"2. Is there anything about H5N1 that might make it more difficult for this specific virus to make that change? (A bit of wishful thinking, perhaps.)"
Not to my knowledge, although the high mortality within the avian and porcine populations is a limiting factor.
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