Pandemic influenza subtypes: end of the year musings

Everyone seems to have an opinion about whether bird flu will be the next terrible global pandemic. In current parlance "bird flu" means human infection with the highly pathogenic avian influenza/A subtype H5N1. There is no doubt that this is the 800 pound gorilla in the global health room at the moment, but not because it is more likely to become a pandemic (NB: pandemic by definition is a globally dispersed sudden increase in infection among humans; the same situation for animals is called a panzootic, and it is plausible to say we have an H5N1 panzootic for birds now). On the basis of biology humans are potentially susceptible to influenza viruses, although only the H1, H2 and H3 subtypes circulate or have circulated in human populations. But a handful of human infections have also been reported from H5, H7, H9 and H10 subtypes, although except for H5 the infections have been relatively mild. Out of 103 cases of the non-H5 subtypes there has been only one fatality (H7N7, one fatality with 88 non-fatal cases), whereas the current official tally for H5N1 gives 213 deaths in 346 cases (61%). Which is why the H5N1 gorilla weighs 800 pounds. This influenza/A variant is a remarkably virulent virus. Is it the most likely virus to cause the next influenza pandemic?

Recall the terminology here, as it makes distinctions that are important. A virus is pathogenic for a host if it is capable of infecting the host cell and cause disease in the host. So there are two criteria for pathogenicity: it can infect the cell; and the host organism gets a disease. This last criterion is vague. The "disease" state might range from very mild or hardly noticeable to fatal. The underlying idea is that the infection was in some sense parasitic, i.e., the virus reproduced itself with the host cell machinery at the expense of the host. That cost might be tiny or catastrophically large, but it wasn't neutral or beneficial (symbiotic). The degree to which the cost of the typical infection is on the serious side is the virulence of the virus. Virulent viruses are by definition pathogenic, but in addition they cause serious disease. By this terminology the H7, H9 and H10 are human pathogenic viruses that aren't very virulent (the most frequent disease symptom was conjunctivitis, "pink eye," in the Netherlands H7N7 outbreak of 89 cases). There is a bit of special usage in the flu world here, which we should also clear up. The avian version of H5N1 exists in two main forms that differ in virulence, called confusingly low pathogenic and high pathogenic. To be consistent with the terminology used in the rest of infectious disease epidemiology they are both pathogenic viruses, one of low virulence, the other of high virulence. The standard test for high path was to see if it killed chicks. These days it is more common to look at a genetic feature, the presence of extra basic amino acids at the cleavage site of the hemagglutinin protein.

What bearing do these distinctions have on which of those influenza subtype is likely to become the next pandemic strain? None, really. They are all subtypes to which humans have had little prior exposure so there is no pre-existing immunity to the main antigen (the one designated "H"). It could also be a subtype not listed as having caused human infections, like an H6 or an H13. The thing that will decide whether a new subtype becomes pandemic, in addition, is whether it is easily passed from person to person, as is "ordinary" seasonal influenza (currently certain H2 H1 and H3 subtypes). This is still given by yet another term, transmissibility. On that list of non-H1 to H3 subtypes pathogenic for humans the most transmissible was H7N7, so on those grounds one might expect this to be the next pandemic. Why aren't we more worried about it? Because a pandemic of "pink eye" is not the same thing as a pandemic that has a 60%+ case fatality ratio (CFR), the way H5N1 does. For comparison, the horrendous 1918 flu had an estimated CFR of under 3%.

All of these influenza subtypes mutate with ease. Most mutations are bad for the virus (in the sense that the mutated virus replicates less well than the unmutated version). So ease of mutation isn't going to tell us which is the next pandemic subtype. We also don't know the features that make an influenza virus easily transmissible. There are likely multiple combinations of features that can do this (i.e., many roads to the same end), but we don't know what they are. We don't know how these subtypes interact when they circulate simultaneously. For example, if another N1 is circulating, does this make it less likely a second N1 virus coupled with a different H will also gain a foothold? How likely are they to infect a host simultaneously? As if these questions weren't themselves of key importance, we also don't know the relationship between transmissibility and virulence. They are logically and biologically independent in general, but changes that affect transmissibility might also affect virulence. Because we don't know any of these things (and lots more besides), it is not possible at the moment to quantify the probability of one or another (or any) subtype to "go pandemic." Experts can make judgments ("subjective probability") based on evidence, but at the moment the evidence isn't strong enough to narrow the huge range of plausible judgments. The best we can do is make some assumptions, for planning purposes. Those assumptions are the source of most of the contentious arguments over the adequacy or lack thereof about pandemic preparedness.

Because perseveration is a characteristic and privilege of the aged, we will repeat again in this last bird flu post of 2007 what we have been saying here since late 2004. The best way to prepare for an influenza pandemic is to do those things which make for a robust community, especially building and strengthening the public health and social service infrastructure. This is like repairing the roof on your dwelling. It will help protect against heat, cold, rain, sleet or snow. It won't keep you safe from an asteroid or a nuclear attack. A strong public health system also won't protect you from a pandemic with a 30% attack rate and 60% CFR. But it will help with a hell of a lot of other things, including many of the most plausible candidate influenza pandemic viruses.

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Of course the new information regarding pigs infected by an avian virus is dangerous. In 2003 there were over one thousand people infected by H7N7.
But what about the 8000 pound gorilla, that is about to start kicking serious butt?
WHO's alert system for bird flu defines Stage 3 as no or very limited human to human transmission. Stage 4 is defined as evidence of increased human to human transmission.
We know that recently in Pakistan, a human chain of bird flu included about 10 people, and human transmission lasted for almost 2 months. This fact in itself would justify going to Stage 4 alert level.
Do WHO representatives want to wait until whole villages are infested with human to human transmission? If so, it will be too late.
Nature is overcoming man's ability to cull all the dying birds all over the world, in time to stop the spread of H5N1 to humans. Many people in the world either do not care, can't read, or don't have protective clothing, to stop the spread of H5N1 from birds to humans. And the number of birds dying is exploding expotentially. In Indonesia they sometimes throw the dead birds into the rivers or streams.
What often happens is one person becomes sick after contact with sick birds, and then a chain of human to human transmission spreads from the index case to family members and friends. In Pakistan you had h2h2h2h.
Although governments and WHO constantly insist all these people are being infected by birds, this is not true. All you have to do is look at the time gap. If all became infected from a common source, there is a very high probabllity they would all become infected within 2 to 4 days.
But in many cases, friends and family members of the index case keep getting sick with bird flu for a month or more.
Right now in Egypt, there are 2 people dead and 2 in critical condition, with a very virulent strain of bird flu.
And the owners of the commercial farms are going crazy trying to cull all of the sick birds, plus there are plenty of small bird farms that are a threat.
But of course, pigs were a mixing vessel for spanish flu, H1N1. And it is still possible pigs will again become a mixing vessel, to produce another pandemic.
If H7N7, a very contagious virus, combines with H5N1, then the game is probably over. And the eyes would be the first target? How many would go blind?
And of course WHO doctors were very brave to go into Pakistan to investigate the spread of H5N1. They could have been killed. But the public relations representatives of WHO are the problem. They stonewall and distort critical information on H5N1 all the time. They should be fired.

Just a correction to the above comment - the number of people dead in Egypt this week is 3 (probably 4 if the school teacher turns out to be positive).

By Helblindi (not verified) on 31 Dec 2007 #permalink

Herman, phase 4 is defined as clusters up to the size of around 25, so we are nowhere near that, even if WHO ends us classifying the Pakistan cluster has having limited h-2-h transmission. This may seem arbitrary, and it is to some extent, but was applied to gie us some yardsticks. Since we really don't know what size is critical in this context it is better than waffling.

I think this is your best article this year revere. Bravo.

By Joe Six Pack (not verified) on 31 Dec 2007 #permalink

I don't think a H7N7 pandemic is as likely as a H5N1-one.
H5N1 did evolve a lot in birds in the last years with
great dynamics.
WHO has a pandemic level for H5N1, none for H7N7.
H5N1 is new, since 1997.
H7N7 is longer being observed but
has never caused a pandemic since >100 years.

Herman - I'm curious. How long have you been watching H5N1? And where are you getting your information about a chain of 10 infections?

Great ending post Revere. Thanks for all you have done the past year, (in fact the past several years) as it relates to public health and H5N1. Your blog truly is great source of objective discussion and remains so because of your leadership.

anon: H5N1 was first identified in 1956. Probably all the subtypes have been around for a long time. H7N7 was transmitted person to person fairly easily in The Netherlands outbreak so by that token is more likely to become widespread in the human population, but no one knows -- you, me or anyone else. It's all guesswork with a huge range of plausible guesses. Why anyone should pay attention to yours (or mine) is anyone's guess.

It certainly looks like H5N1 is the one with the fastest "running start". I'm coming to see this issue as similar to riding in a car. How many people actually get into life-threatening car collisions every year? Not many. But how much money do car companies spend on safety equipment just in case? How much attention do the feds give to automotive safety every year, just in case? Huge amounts of money, time, attention, and research. Almost lost my leg in a bad accident years ago--not interested in doing it again, so I'm careful about using the safety equipment in the car when I drive or ride, even though the risk of crashing during any particular ride is very, very small. "Just in case" is a good phrase. Yes, most mutations are detrimental to the organism doing the mutating, but it certainly appears that the mutations in H5N1 which are detrimental to humans are worsening and/or spreading. Great thoughtful post, Revere. Just some musings. AnnieRN

but WHO does see an increased pandemic likelyhood since the
emergence of H5N1. "pandemic danger larger than anytime
since 1968" or such, they said. They established the
pandemic level page. For H5N1.
Pandemic level for H7N7 is as big as ever, nothing changed.
So, when we consider a H5N1 pandemic as likely as a H7N7
one, then it shouldn't be more than 1% per year.

anon: I've set out my reasoning on this. Feel free to disagree.

revere,

Thank you for a very thoughtful and balanced year end review.

Revere:

How far is your muse to theology?

Revere says: "Those assumptions are the source of most of the contentious arguments over the adequacy or lack thereof about pandemic preparedness." Humility enough!

It reads like a modern version of theology to me.

The best way to prepare for an influenza pandemic is to do those things which make for a robust community, especially building and strengthening the public health and social service infrastructure. This is like repairing the roof on your dwelling. It will help protect against heat, cold, rain, sleet or snow. It won't keep you safe from an asteroid or a nuclear attack.

I agree. This is the best approach. Any time you can do things that have a potential synergistic amelioration of other threats the whole system is made better for it!
Dave Briggs :~)

palwan: Not sure what you mean. Theology is what followers of a doctrine do as scholarly activity. They accept the doctrine and argue about what it means. Theology is not the same as philosophy of religion or the sociology of religion, which study religion from the outside, not the inside. This seems to have little to do with arguing about assumptions about the world that are then used deductively to draw inferences, any more than scholarly activity in art history or literature are analogous. Just my opinion.

revere,

Is the high degree of virulence of H5N1 associated with the surface proteins (forgive my layman language) that define the subtype, or is the virulence associated with internal genetic characteristics of H5N1? If the latter is a possibility, then would it not be possible that a H7N7, H7N2 (as in Wales outbreak earlier this year) reassort with H5N1 and acquire this virulence while retaining the original subtype? This question came out of a thread I started on the Flu Clinic section of Current Events Forum:

http://www.curevents.com/vb/showthread.php?t=85966

In other words, could a highly virulent pandemic strain be brewing as a H7 subtype? If so, how much can we rely on an H5N1 pre-pandemic vaccine?

anon.yyz: This will sound flippant but it is substantive: when you find out the answer to your (excellent) question, tell me. And everyone else. We don't know what causes the virus to be virulent although we see how the virulence appears (cytokine storm, for example). Yes, another subtype could become virulent, in principle, at least given our current state of knowledge. H1N1/1918 was certainly virulent as is H5N1.

Revere: Good points, thanks.

I thought that physics is ahead of biology in interpreting "Paradox", for instance, light is both particle and wave. So, the concept of paradox crosses the border of deduction and reduction, inside and outside. Permeable like cell wall's osmosis.

A fan of Paul Tillich like me, he quoted Descrates "The infinite in our mind presupposes the infinity itself."
It has inspired me to think of the convergent area of science and religious experiences.

Anyways, thanks for this blog - a mini " Fourth Estate" provide open space to share edge speculation and muse.

Here in Phuket, we finished 'count down' a while ago. So happy new year to you and everyone!

Revere,
Great summation of the current situation. I'm hoping you get to do the same thing again next year. (This would mean we HAVEN'T had a pandemic.)

I enjoy reading all your carefully considered commentary! You bring a level of sanity to an otherwise, sometimes neurotic flublogosphere.

Here's hoping for a "Happy" new year.

Thanks. It's well informed, well reasoned, measured, humble posts like this one that have led me to read EF pretty much every day for the last few years.

And as Nell says, your approach is especially valuable given the low signal-to-noise ratio elsewhere (including, too often, these comments).

Anyway, I'm grateful. Best wishes to you all for the new year!

Patch,
I am scared shitless about what happened in Pakistan, and what is happening in Egypt. I live in Colombia, even though I am an American, and I see beautiful children here playing with birds, that are their pets. Those children have a love for those birds, equal to the love you have for your cat or dog. It is incredible, but the birds follow those children around, like your dog follows you.
No matter how much bullshit Revere spouts about how he does not believe in God, I have never, in all my life, seen a person so full of love for his fellow man. If he dies, and if there is a God, which honestly, is beyond me, he will encounter bliss.
Randy and Monotreme are also very special for me. Randy, like me, is not a doctor; but his dedication
to trying to find a solution to this plague leaves me very humble and grateful.
I do not give a shit about 25 as the golden number, for the declaration of stage 4. Tell WHO to get off their ass, because every day of my life I suffer the memory of a photograph of a young girl in Vietnam that died of bird flu.
If you cannot understand my pain, that is your problem, but the pain is severe.
I honestly believe Randy understands better then anyone. He is very special. He is trying to tell you how serious the situation is. But are you listening?
But especially, please go to recombinomics.com, because there, with Henry Niman, you will realize the danger, and how close it is.
If you are not grateful to Revere, to provide us with the opportunity to communicate in regard to the dangers of how a virus can kill or disable you, you have an emotional problem.
Happy new year to Revere, Randy, and Monotreme, and all the other people who with all dedication, post here. I have been posting here since this blog started.
All I ask, with the most deep humility, is that you honor the death of that beautiful young girl in Vietnam, that was killed by this horrible virus called bird flu. I know you will continue to struggle, especially Revere, to stop this horrible tragedy.

A minor quibble about terminology, Revere - as someone who works in veterinary epideimology (specifically with avian influenza), panzootic and epizootic aren't much used. Epidemic/pandemic are also used for animal disease these days. Sure, the etymology isn't correct, but in practice that's what happens (in my sphere of experience, anyway).

By attack rate (not verified) on 31 Dec 2007 #permalink

You must not have read my post in it's entirety. I am sincerely grateful for Revere's leadership and guidance with this blog. It has become my primary and often ONLY source of discussion. He/She is quite fair and objective with H5N1 issues.

I am not as supportive of Dr. Niman views. He appears to have a very narrow minded view. Whether he is right or wrong remains to be seen. There are occasions it appears he has been right. But on others he has not been right. But he seldom cares to consider views outside of his own.

As you point out, I too am saddened by the death of any BF victim, but especially a young victim. But in relative terms, there are many diseases that take a much more significant toll on human life and emotion. BF warrants our attention certainly, but not solely. Surely you must feel the same pain and sorrow, when you see starving children in Africa? There are other issues besides BF. BF poses a potentially high impact threat. But there are issues which pose a more immediate threat.

Whether or not Revere believes in God is his business. I'd prefer he not knock my religion, but this is his site to do with what he pleases. But I would agree, that Revere has many Christian virtues and characteristics. And it's my belief that he may gain some reward for that. That's my opinion, I really don't know. I realize many if not most here, have no interest in God (at least the way I do).

This also is my opinion, but I don't think your view is very objective. And it seems at times as if you slant the facts to support your ideas with little regard to credence.

My post above was primarily directed toward herman.

http://crofsblogs.typepad.com/h5n1/
I know some will be pissed off, but the number infected in Egypt is now 4, not 3. Although you will laugh, Egypt may easily reach 25 human H5N1 infections, the magic number, very soon, for the declaration of stage 4.
This virus cannot be stopped in birds by killing birds, called culling. And nature will not allow it to be stopped in humans either. As it spreads in birds, it will infect humans.
The strain of H5N1 in Egypt is deadly. I hope to hell, if the pandemic hits, it is not this strain, because if it is, many will kiss their ass goodbye.
Take your mortician out for coffee, while there is still time. You may need a favor soon.

Patch,
I do not give a shit about your credence. All I really know is I saw the photograph of a young girl that died of bird flu in Vietnam. Please be grateful we were not the ones in the photograph, because if that were the case, we would both be exploding into eternity and nothingness now.
Of course Revere is an atheist. That is good. Really, you are correct, in that I should not say anything about Revere and religion. I totally respect your position, and I thank you for your criticism.
As far as bird flu not being a major threat, you are again correct for the present. XDR-TB for me is a greater danger. And it is spreading fast.
Many of those who died of Spanish Flu also had TB. But now we have a new incurable TB. What happens if TB, Aids, and Bird Flu explode simultaneously?
It is possible your are correct about Niman, because I am not a scientist. Perhaps you are. Really, I do not understand very well how this H5N1 virus spreads. But many things he says seems to make sense. He thinks H2H is very common. I agree.
But the future is a diferent matter. Spanish Flu killed about 100 million, with a 2 or 3% mortality rate. But at present, bird flu has about a 60% mortality rate. Please tell me where in the hell they will put all the bodies, if a bird flu pandemic hits, and the mortality rate stays at 60%? How many would die in that case?
What is happening in Pakistan and Egypt in regard to bird flu is not good. Too many birds are sick. That may mean more human H5N1 infections, do you agree? What is your opinion?

"Judging from what the Flu Clinic has picked up, Egypt has a lot more suspected cases, scattered over a wide area. Whatever is going on there, it's not a family cluster."
Please note. There is an explosion of human bird flu in Egypt. There are 4 confirmed cases, but from an unconfirmed viewpoint, all hell has broken lose.
I sincerely apologize from posting twice.
Sorry.

The other 800 pound gorilla is that by the time bird flu is ready to go pandemic, it will already be Tamiflu resistant.

Miso,
This 800 pound gorilla is a real threat. Below is an editorial summary for 2008.

The virus that causes avian flu is still around, killing birds and an occasional person. It continues to mutate. Scientists tracking the virus have seen subtle changes that make it very likely that this year we are going to get a strain that not only goes from birds to birds and birds to people, but also from people to people. That is when we get the real chance of a pandemic.

The evolution of the virus says it is getting close to getting ready to do us a lot of harm. Last year a bird flu vaccine was approved for human use. How effective it will be or how much of it will be available is not clear. In 2008 the nations of the world better get ready to deal with this time bomb that has not stopped ticking.

My opinion is that you should take a break from reading about BF for awhile.

It remains troubling, that BF continues to haunt us. But if you read Crof's blog with an open mind, you would have noted that that by sheer (stated) numbers, BF is slowing down, rather than speeding up.

Just because Niman and you believe H2H is common doesn't make it so. Humans come into contact with poultry in BF infected countries regularly, almost constantly. Yet in general, it's appears rare for B2H infections to occur and even more rare for H2H transmission.

It doesn't take much imagination to realize if H5N1 does become the next pandemic, with a high attack rate and high CFR, we are looking at a drastic world changing event. Thankfully, that scenerio is imaginary at this point. And no one knows if it will become a reality. Not Niman and not you.

That's why I was referring to your credence, not mine. I have no credence because I don't know. And I believe that there are a select few that have credence on this matter, who have a grasp on the intricacy of this menace. You aren't on that list. So if you care to speculate, that's fine. But respectfully, my opinion is for you to tone it down a bit and take a step back to review and state ALL the facts and not just those that support your current view.

If nothing else, it may help you sleep at night.

Respectfully,
Patch

Patch,
Denial is a river in Egypt.

Does any one know whether the first wave virus of 1918 pandemic has ever been typed? I am a lay person with some curiosity.

The first wave strain had efficient H2H capability, but not as virulent as the second wave. If the first wave was typed H1N1 then the reasonable guess was it mutated into a more virulent strain in the second wave. However, if it wasn't typed or if it was typed as some thing other than the H1N1 that we know today, then it would indicate the possibility of the second wave strain being a reassortant with the added virulence. The public conscious for now is filled with the notion that if a pandemic strain arise out of H5N1 mutation, then it can maintain virulence, but if H5N1 reassorts with a human seasonal flu strain, then it is reasonable to expect a lower CFR due to partial immunity. No disagreement there, but this notion gets abbreviated into "if it is mutation it is dangerous, if it is reassortment it is not so bad".

I am curious about the possibility of an H2H efficient avian type with low virulence (e.g. the H7's) as a first wave reassorting with H5N1 to form a second wave.

Patch:
Your post provides a poised stance to think of H5N1 and its threat, thanks.

My opinion is that you should take a break from reading about BF for awhile.

I think this is sound advice, but not likely to be heeded. Herman reminds me of - and may be, for all I know - a former commenter named Juan who had a morbid fascination about BF that sometimes seemed to me to come perilously close to enjoyment. I had the odd sense that he'd be disappointed - on some level - if the events he warned about constantly, and at great length, didn't materialize.

I'm not surprised when people have this attitude, and I realize that they may not fully understand it themselves. But also think it's counterproductive and possibly even dangerous.

In a perfect world, some of the more long-winded, grindingly repetitive, and casually speculative commenters would confine that sort of posting to their own blogs. (It's free, last time I checked.)

I don't think that's gonna happen, though....

Phila: You are correct. herman is Juan is William before that. He is getting very close to be banned as a troll. Don't bother to "apologize" herman. We've been that route before. I've let you stay here because I let pretty much everyone stay here. But you also know I have limits. And you are very, very close to them.

paiwan, thanks. That's precisely what I was trying to say.

miso - If that is more than sarcasm, then I believe both you and herman are the ones in denial. I don't deny that H5N1 poses a very real threat. I never have. On the other hand, as Revere points out in a previous post, there are some who are focused so intently on H5N1 they see only the fatalistic outcome. To rationalize their fear, they look for the very worst of the news, to prove themselves right.

I'm scared too. It's appropriate, in my opinion, to fear and prepare for an H5N1 pandemic. It's appropriate to prepare for any disaster as such. But it is in appropriate, to turn speculation into fact or consider only the worst case scenario. That's fear mongering. A deadly H5N1 pandemic with 25% (or more) of the world population being knocked out is possible. But as anon.yyz points out, it's also possible that a reassorted H5N1 may be a much, much tamer version. If I were to state that I'm convinced a reassorted H5N1 would result in a pandemic more comparable to recent pandemics ('68-69), I would imagine you would contradict me. But believe it or not that IS possible as I understand it.

Nobody knows....and few understand it intimately enough to speculate.

In Qalyubiyah detained Hospital pathogenesis Banha Safa Abdel Mohammed, a nurse at the health unit necessary for the village's center Shebin Spans on suspicion of being infected because they are raising birds at home, and it appeared the symptoms of the disease.

The above translation describes the hospitalization of a suspected H5N1 infected health care worker in Qalyubiyah. Although she raises birds at home, the number of confirmed and suspect H5N1 infected patients continues to rise (see satellite map). In addition to the five confirmed cases, there are twenty-one suspect cases, including one fatality in Cairo, a family of four in Port Said, and a father and daughter in Menoufia.

This dramatic increase in confirmed and suspect cases is alarming. In the past week, four of the five suspect cases have died, as has one of the suspect cases.

This will probably be the last post I will be allowed here. I just wanted to say goodbye to Randy.
Egypt will soon kick the world in the ass as bird flu explodes there.
I mean no harm to anyone, although my emotions are a little strange.
Goodbye.

This is all very shocking.My father has been a Dr. 64 years.My entire family are scientists...for generations.I am a former National Chess Champion and have followed this pandemic topic non-stop for more than TWELVE YEARS.I dared to put the word "GOD"in my own personal diary...and found my diary deleted by the "powers" that be here.By what right?? I have...and still do...travel the world explaining to crowds how all these dynamics are coming together...and why.The leaders here complain about OTHER groups filtering info but have no problem deleting things THEY don't want to here at this site.

Greg: Are you saying I deleted a comment of yours because it had the word "God" in it? Since I never do that and delete comments very rarely and usually because they are spam (the "sex shop" kind) you are mistaken. If you are at all familiar with the conversation here you know that lots of comments are about religion and they don't agree with our views. Indeed many of them are of the type a sane blogger would delete because they are disruptive, off topic, nonsensical or many other things and they still remain up because I am not in the habit of deleting comments. Talk about God here all you want as long as it's on topic or even tangentially related to the topic. If you want to come here to post about your own concerns, unrelated to the blog, I suggest instead you start your own blog. It's quite easy. I recommend Blogger for beginners.

Patch,

I am a layman. I am not leaning towards a mild nor severe pandemic. I just don't know, but I would like to understand more about the different possible outcomes, and more importantly the different pathways that will get a strain to become pandemic capable.

And to your credit anon.yyz. Your desire to learn and discuss is a good thing. I'm here for that same reason. It's good to listen and try to process what Niman is saying too (as herman nearly quoted). That seems a much more fruitful and educational process than blindly telling us "how it will all go down".

For example, a practical discussion about the statement "dramatic increase in confirmed and suspected cases is alarming.." might start by pointing out that it's flu season and while it may be cause for concern, at least some increase is to be expected. We might discuss possible reasons that ALL influenza cases increase this time of year and how that may be applied to H5N1, instead of drawing conclusions that H5N1 has become more efficient.

I think Revere is quite lenient in the discussion here. I'm not sure he/she/they needs the compliment, but I continue to stand by my belief that this is the best H5N1 blog anywhere. You have come to the right place to get your questions answered anon.yyz.

Jesus Herman.....Pick a handle and settle down for Gods sake... Or is it Zod? Look I have told you before, you dont crap on Revere's carpet and not exact a response. I have only seen him warn one other person here and it was AF. There is web tracking and tracing herman. Revere is very lenient and as long as you are pretty much on subject he will let you rant away. Its a leftist leaning blog, I am one of the few voices of reason but there are limits to Revere's and everyones tolerance. Mine are quite high but zero for trolling......I have only seen him one other time do something else and it was to cut the thread on a subject because it was getting flat out NASTY and probably beyond the limits of the ISP. All ISP's have the clause that you shall not, will not disparage other people, use foul or profane language that is directed at others, or my favorite... try to pickup 12 year olds when you are 48 years old and living in a trailer in Witchita.

Apologize, drop the other couple of names (remember, we can track you) and blog away. You screw up again and I'll get the rope myself. If a guy is lenient to begin with, then you are warned, then warned again I think it becomes more like a taunting then.

By M. Randolph Kruger (not verified) on 01 Jan 2008 #permalink

Revere: New Year needs new questions. If H5N1 virus should unfortunately trigger the next influenza pandemic, will it eventually become another seasonal influenza virus (i.e. post-pandemic) and be added to our annual seasonal flu vaccine composition? As you know, in the US alone it is estimated that over 30,000 deaths a year are seasonal flu-related. How many more deaths would be added to this number if H5N1 becomes a seasonal influenza virus? If H5N1 influenza has a CFR of over 60% in about 7-10 days from the onset of symptoms, will most of us be able to get over it in a course of 7-10 days like other seasonal flu (but the CFR for the 1918 H1N1 influenza pandemic was under 3% as you mentioned)?

By flulearner (not verified) on 01 Jan 2008 #permalink

Herman says: This will probably be the last post I will be allowed here.

Herman, I am not the host, I speak for myself. The first time, I read your post, I was touched. Second time and third time I need more perspectives to evaluate. I sense that Patch has respected for your inputs, but he likes you to be opened to different perspective, perhaps take a break.

As for your wrong doings of using different names, that was related to integrity. But I also see it has been forgiven. I suppose that most of us stress on the attitude to trust each others. We are all not God, our knowledges all are not complete.

Move on from here, I like to read your posts from time to time. As I said I speak for myself.

flulearner: If H5N1 became easily transmissible but kept its current virulence, it is hard to say what its subsequent history would be. The only comparable virus we know of might be smallpox. Presumably after a rather horrendous initial appearance the human species would develop immunity to the circulating strains and clearly it would be incorporated into a vaccine. That's after a period of genuine public health catastrophe whose other effects in particular geographic and national areas would be hard to estimate. This is an extreme circumstance I hope will not happen.