Bird flu virulence: come what may

Currently estimated bird flu case fatality ratio remains catastrophically high, somewhere around 60%. This may or may not be an accurate estimate. Case fatality is the ratio of cases that die to the number of people diagnosed with H5N1 infection. If we are missing many cases then our estimates of case fatality will be biased upwards. On the other hand, it is possible we are missing many deaths from H5N1 for the same reason: the case was not diagnosed. In Indonesia, for example, there are hundreds of thousands of deaths yearly from severe pneumonia. While the overwhelming majority are not bird flu, most are not diagnostically investigated for H5N1 infection either. Missing these deaths biases case fatality estimates downwards.

Whatever the true case fatality is at this moment, it appears the virus has not changed in a way to make it easily transmissible from person to person. A major question has been what would happen to the virus's virulence, its capacity to cause severe disease in infected people, if it became more easily transmissible. We have discussed this subject numerous times here (see, for example, here, here, here, here, here and here). We pointed out that the conventional view that virulent viruses moderate with spread is not necessarily correct, although there are viruses that have done so.

The idea underlying the conventional view is it is more advantageous for the virus to produce moderate disease so it will spread more easily. However there are arguments to the contrary and examples to go with them. Neither smallpox nor HIV have moderated their virulence despite maintaining pandemic status over long time periods. At present we don't know the biology of H5N1 virulence or infectivity or its epidemiology well enough to know if increasing one will increase or decrease the other.

Now the same conclusion seems to have been reached by influenza researchers:

There's no guarantee the H5N1 avian flu virus would become less deadly to people if it triggers a pandemic, a new report from the World Health Organization warns.

A group of eminent influenza scientists gathered by the WHO last month concluded there is no reason to believe that the virus, which kills roughly 60 per cent of people who become infected, would become any milder if it evolves to become a pandemic strain.


The WHO scientist who convened the meeting cautioned, however, that the question of how lethal an H5N1 pandemic might be is the scientific equivalent of a black hole.

Modern science has never seen a flu virus as nasty as H5N1, and there is no way of knowing if the virus can become easily transmissible among people or what an H5N1 pandemic would look like.

"It's one of those things that you hate to conjecture," said Michael Perdue, an avian influenza expert and scientist with the WHO's global influenza program.

"We just don't know enough about this virus, a whole new subtype for humans. . . . If a new H5 enters, it could be more lethal than anything we've ever seen in history. (But) who knows?"

"I think it's anybody's opinion because it's just so completely unknown." (Helen Branswell, Canadian Press)

In other words, if H5N1 becomes pandemic the consequences could be anything from a mild seasonal flu-- to "I don't even want to think about it."

But think about it we must. It's still the best way to get through whatever happens.

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The virulent influenza A subtype H5N1, known colloquially as bird flu, has caused sporadic cases of human disease but has not yet become a pandemic strain. There are several things which still separate H5N1 from the kind of seasonal influenza infections that are a serious periodic public health…
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Community planners need to consider what the untreated fatality rate will; be; they must be able to see there are not going to be enough enough vents, antivirals, ICU staff, ect..

Also, consider the collateral deaths if imported Rx meds, institutional care, emergency medical care, firefighting, law enforcement, power grid, is disrupted by pandemic.

If officials don't want to think about it, some of the public would like to, as they wouldn't want they and theirs to just get blindsided.

And, current fatality surge planning will fail. Ungood.

By crfullmoon (not verified) on 06 Nov 2006 #permalink

I spent a significant part of Saturday writing individual emails to every single US senator, going over some of the points above and urging them to instigate FEMA to set up community preparedness centers across the US for distribution of vital supplies in case of a pandemic. I pointed out the government's current plan is reactive and largely a waste of time and money. If more people would write at least their own senators and perhaps a few other key players (just need one letter and keep pasting) it might get their attention.

By mary in hawaii (not verified) on 06 Nov 2006 #permalink


I think the public would rather trust their childrens' lives and their communities' safety to - themselves!

It wouldn't take much time and money to tell the public the truth, (start with the key phrases from the first 9 of the WHOs 10 things from Oct 2005...and, the individual checklist, that mentions words like "difficult" "impossible" "disruptions")

and they will stock up at home, and, chip in to help their first responders, and, come up with solutions for their local contingency plans and vulnerable populations. They will even figure out how to cope with mass fatality burials; give old 'Yankee ingenuity' a chance; New England has to become more self-sufficient. Winter is coming.

By crfullmoon (not verified) on 06 Nov 2006 #permalink

Kudos to you MiH! My significant achievement on Saturday was to convince my wife that we need to prepare. Although it may be relatively late in the game, she reluctantly agreed to capitulate to my wishes to prepare with one condition... that we don't tell people we are doing this. Which means she still thinks I am nuts to worry about this.

I convinced her by just being honest. I told her that I had quit talking about it because I didn't want her to think I am nuts. But the feelings of guilt I was having and would have if it did happen, and I knew, and I didn't do anything to prepare for her and the kids, was more that I could stand.

Although I still am somewhat unconvinced that it is a certainty that we will have a deadly pandemic on the scale of 1918, I feel there is enought of a chance that not preparing is taking a bigger chance! I reminded her how mad the grocery stores get around here (Charlotte, NC) when snow is in the forecast and told her that if we wait until the newscasts announce the beginning of a pandemic, then it would make those snow panics look like shopping on Tuesday afternoon, and it would just be way too late!

So, I am not any closer to saving the world, the US, or even my friends, but at least I can get started on my family! I have also asked her to begin reading this blog, so who knows, in a month or two, maybe she will start sending letters to our senators!

MiH/David... William on the sidelines. What everyone misses is that this is a STATE run problem. Not unlike Katrina. William would have you believe that the FEDS can ride in (in any situation) and either save the day or screw it up. Not so. The only way the FEDS can do it now is if there is a complete breakdown of civil order. That clause was put in due to the cluster that was going on in Katrina. There will of course be lawsuits, reach down verdicts by the Supreme Court but yep it would hold. The greater common good thing. Anytime anyone stands in the way of the common good its over with but the shouting... Unless you are talking about imminent domain by cities.

NOW we move to this thing that Mary is talking about and honey you keep right on talking. Squeaky wheels get the oil. FEMA is a little agency with a lot of money. They can and will direct the activities of the various federal agencies to keep the infrastructure going. If that means troops at the supermarket then so be it. It could also mean troops at the hospitals. Not to treat, but to allow order so those that are there can treat. It also means that they can order quarantines, and isolations but the states will likely beat them to the punch. Understand that in a declaration of martial law, that the Constitution itself is suspended but that too will be challenged immediately. No its about ensuring that order is maintained. Not some government takeover. There is no way for them to collect taxes during one of these things, they arent crazy. If the bills dont get paid, then no one works. The government would simply dissolve.

A 5% event would be horrendous. But if G.I. Joes are out there they will maintain order...harshly. But only on orders. The NE is in my opinion the LEAST prepared group because and this isnt a slam folks but it is reality the group that has come to expect all things of government. The size of government will reduce by attrition overnight. The ability therefore will reduce with it to cope. Thats when the orders from the governors (state of emergency at the least) will go to the President and thats when everything will start happening. MIND-Once it goes federal it is not over until the governors sign an order stating that they are now able to cope and control. So we could and will have 50 signed orders and everyone expecting support. Not going to happen. Mary, there is a large chance out there in HI that they will not allow any aircraft flights other than transient overflights. Boats may not port, nor may they want to. Italy in 1918 in Naples wouldnt let boats port up for three weeks (they let them in when everyone had it) and then only to refuel. A governor can rescind the order in writing to the President if things get too nutsy. They may allow the USGOVT to maintain control of those things that have federal impacts such as powerplants but even that will slowly and inevitably go away.

Its one hell of a mess and the reason that no one wants to believe its coming is because the effects are like standing on the beach at Banda Aceh....Hey whats that noise. Urps, look at the ocean pulling back. Didnt I read about this in science class? Man look at them waves...Tsunami!!!!!!!!!!!!!!! Aargh! The unthinkable is possibly about to happen and well, getting to say to hell with house payments isnt so bad either.

By M. Randolph Kruger (not verified) on 06 Nov 2006 #permalink

M. Randolph Kruger, I'm about to give up on the NE.

;-) Not that you need to know.

I wasn't doing much good anyway.

By crfullmoon (not verified) on 06 Nov 2006 #permalink

Tsunami!!!!!!!!!!!!!!! Aargh!

No, more like Flunami......

Even if H5N1 maintains a virulence of 60%, which it may,there does not appear to be that much of a threat of a pandemic.
Since 2003, in the entire world, there have been about 256 people infected and 152 deaths. That means it is extremely difficult to become infected with H5N1, even if you try.
"Neither smallpox nor HIV have moderated their virulence..."
Of course the above statement is correct. But:

MORE than 250 people in Nelson Mandela Bay have been diagnosed with multi- drug-resistant TB and some of them are possibly living with the deadly extreme drug resistant (XDR) TB.

At least 18 people in the metro have already died from multi-drug-resistant (MDR) TB, but officials will not confirm that the cause of death may have been XDR TB.
MDR and XDR-TB are epidemics now. Doctors in South Africa are saying there is not much reason to give HIV patients drugs for HIV, if XDR-TB is going to kill them anyway.
Could XDR-TB move into the general world population. Of course it could. I live in Colombia, South America, and many people here, due to lack of food, have weak immune systems. XDR-TB attacks those whose immune systems are weak. And there are plenty of HIV patients in the US, plus
many people who do not eat well, due to lack of money.
So while we concentrate on H5N1, a new deadly disease,
XDR-TB could kill thousands.

If either come William I suggest you get the hell out of Dodge. Its a moot point, no one disagrees with the XDR-TB but its not going to jump on us that fast. H5 would span the globe in weeks and yes I am monitoring the TB thing. My bet is that both come and beat the living shit out of us as a species.

Why dont you see if Revere can set you up on a TB-Wiki. Thats where this flu blog started. Who knows you may get more traction on it there than you do here.

By M. Randolph Kruger (not verified) on 06 Nov 2006 #permalink

If I am understanding what some of you have said, the US government via FEMA is not involved in preparation for a pandemic, it is the state governments instead? Is that because they already allocated and sent down funds for this to each state to use as they see fit, or what? And if so, what state agency would be in charge of this? I am - admittedly - confused. Would like to know where best to direct my energies and emails. Thanks.

By mary in hawaii (not verified) on 06 Nov 2006 #permalink

MiH: The federal gov't in the US is involved in many ways but recognizes that the response will be local. In our view they have failed primarily in not providing the incenive, reosurces and infrastructure to allow hard pressed state and local health departments to rebuild their detriorating, anemic and marginalized capacities.

The response will be from state departments of public health and safety, local (city, county) health dpeartments, the official and non-governmental network of social service agencies and new organizations that wil spring up spontaneously to cope with the new unenvisioned problems a pandemic will bring.

The whole thing is an exercise in community mobilization. We have been advocating from the beginning that individuals work with their neighbors, local officials, friends and family to support each other. We think this is a better use of energy and resources than personal preparations, since like all plans, when thing happen, you will probably find it is different than you thought and you will want help. If you dn't enter into implied compacts that helping each other is the way we will get through this, the help won't be there for you when you need it.

Just our opinion. But you asked.

M.Randolph Kruger,
I want to thank you for responding to my post. You have exceptional insight regarding XDR-TB and H5N1. I am sure your actions and your efforts to inform the public regarding these threats is appreciated by many people, including myself.
I believe XDR-TB will arrive as an epidemic in the US before the arrival of an H5N1 pandemic. A doctor at the emergency WHO meeting in South Africa said:
"HIV has the potential to fast-track XDR-TB into an uncontrollable epidemic that we will not be able to manage or treat."
Just in South Africa there are 6000 MDR-TB cases anually,and many of these cases may actually be XDR-TB.
The only positive part is MDR-TB cases tend to cluster less than regular TB cases. But there are many locations in South Africa with clusters of MDR-TB, defined as 3% or higher among new patients or total cases in excess of 500.
HIV is causing MDR-TB to spread at a rate 6 times faster than it would alone. In 1991, during an outbreak of MDR-TB in New York City, it cost the government $1 billion dollars to stop the spread. If it hits the US, how much will it cost to stop it? And it infects anyone with a weak immune system especially hard. The elderly, anyone with a disease that has weakened the immune system, those who have been treated with radiation for cancer, and of course HIV patients, are all vulnerable.

mary in Hawaii,
If an epidemic of H5N1 or XDR-TB arrives in the US, and I believe the first epidemic to arrive will be XDR-TB; FEMA will have almost total control if the president declares martial law.
Public Law 109-364, or the John Warner Defnese Authorization Act of 2007, section 1076, revises the Insurrection Act and the Posse Comitatus Act. This law was signed by the president about 2 weeks ago. These two Acts were passed to stop the president from using the armed forces as a police force within the US. Section 1076 grants the president the power declare martial law. This means he is now free, after declaring martial law, to used the armed forces as a police force within the US. This means US citizens will fall under the Military Commissions Act of 2006, if they act in a violent manner to resist martial law.
They will be designated enemy combatants by the president or his designated authorities.
Under martial law, cities can be quarantined to stop the spread of the disease. That means you will not be allowed to enter or leave the city.
Many people refuse to accept that the president has this power, and will probably use it during a pandemic. Under martial law the US Congress, and the Courts will be closed down until the emergency is over. There will be no more elections until the emergency has passed.

I don't get it why you people voted him for your president...
All the World is suffering from him.

Thinlina: if Gore or Kerry had been elected instead you would probably be writing the same exact words... blaming All the World's suffering on the US...

I probably wouldn't be writing the same exact words. Based on the experiences of the father Bush it was highly probable the son Bush wouldn't be a very good choice for the US nor the rest of the World.

whine all you want, but the 'rest of the World' doesn't get to vote for the US President... and this will be my last comment on this since this is really not the proper forum or thread for political debate... my apologies to Revere...

Oh, I'm SO sorry for critisizing the "Quantanamo President". Please accept my apologies.

Revere...thank you for the insights. I will be emailing my state depts of health and all the other local sites you mentioned shortly, and will continue to irritate them as best I can until they do something proactive to set up community based pandemic supply and care centers. my place of work the day after the last presidential "selection" it was as if someone's mother had died. We were all in shock and mourning. And we were all dead certain that the election had been stolen by fraud and malfeasance by election officials. A couple of investigations were launched, lawsuits filed, and nothing ever came of it because our country - like yours, whereever that may be - is controlled by corporate interests. Get your head out of the sand...we are all equally screwed and all our leaders are equally corrupt. It goes with the territory of politics and power. "Free elections" cost a fortune: who do you think supplies the money? It's just a quieter coup, but a coup none-the-less.

By mary in hawaii (not verified) on 07 Nov 2006 #permalink

Nothing like a difference of opinion on politics or religion to get a good argument going!

To thinlina: had Bush not been elected you may have been writing those same words in Arabic or Farsi or???

Good news for all you Bush haters... he is planning on visiting Indonesia on Nov 20th... guess all you guys can hope he gets the Bird Flu while there (

David - LOL, my thoughts exactly!

By L Gambill (not verified) on 07 Nov 2006 #permalink

David: Yes, every election is a coup. a corporate coup. The corporations give us a "choice" of tweedle dum or tweedle dee, and it doesn't really matter which one we "elect" because both are essentially puppets of the corporate puppeteers who pull their (purse) strings. And I don't particularly like or trust any of them. Just that some are more blatantly and enthusiastically in the pockets of their controllers than others, which makes them a little easier to spot.

By mary in hawaii (not verified) on 07 Nov 2006 #permalink

mary in hawaii: I gotta say I generally agree with you. I usually look at the dems and reps as just two sides of the same (tarnished) coin. But I did vote today if for no other reason so that I would have the right to complain ;-).

"thinlina: (over) half of us didn't vote for him.
Posted by: revere | November 7, 2006 11:20 AM"

Well that's good even though you people should study more mathematics. At least those ones who count the votes :)

Anyways, it's good to know that (more than) half of Americans are sensible people even though they don't have equal votes.

MiH, I agree.

Neal, are you claiming that the arabese people have beentrying to conquer the world? ;D Well, maybe, but first they need something to eat.

Well folks I gues we now know how people feel about Iraq and Bush and yes they did speak. I for one as a moderate Republican was saying that we would lose in many states simply because of Iraq. Americans hate losing and we were/are losing Iraq slowly but surely. I for one as a moderate spoke at a few rallies. I said its time to pull the gloves off. You dont negotiate with terrorists. I wouldnt have occupied the country any longer than necessary. Thats only being long enough to get an airfield built big enough to take B52's, B-1's and B-2's and then launch them against Iran. Yup, smack them upside the head. We aint done yet Thinlina, we ARE going to do Iran before Bush finishes up.

Iran smokes a bomb like the Norkos and they are done. I am sure you think that Bush is crazy. Fine, opine if you want, but dont think that for one minute that every vote here doesnt count. Tthe very thin majority of people spoke yesterday and they took the House and maybe the Senate. Hardly a peep about voter fraud or crappy voter counts. Rigged? If it was rigged the Republicans would have cleaned their clocks. It wasnt. As an election judge I can say that it was the cleanest election in years and the turnout across the country was huge. Attaboy to the US citizens. Now we will have starting in January endless investigations, attempts at impeachments, and on and on ad nauseum. The tax cuts will be allowed to die, the stock market will drop back to the mid-11,000's, our 4.2 unemployment will rise back to about 5.6% nationally or maybe better and they will increase taxes and the minimum wage which makes us already uncomptetitive in the world economy.

MIH. Yeah Mary, you need to talk to the Hawaii State EMA for what the "great plan" is for bird flu. Its not too terribly different from the Federal one and letter writing IS effective. But its a local disaster and will be when it comes. Both suck because they could use the entire state and Federal budgets for the next 10-20 years. It still wouldnt be enough to guarantee even one survivor. Some will assert I am wrong, but has anything so far done any good? If so I am waiting to hear about that one. You might make it if you are intubated, maybe not. Whatever the case you are one screwed up monkey for a while afterwards if you do survive. Mild case... Shit, the mild cases look like someone who was on the death march to Bataan. I cant give you any really good answers Mary. The front office is being innundated with requests about what to really do about it. The answers coming back are to preserve the inffrastructure, shelter in place, hope you dont get it. The military will be used to protect the infrastructure and thats about it.

Now folks I am no where near as in a state of dispair over the elections as many in my party. its one group of thieves being replaced by another group of thieves. Bird bug or TB might not be such a bad thing because accountability will be there fast and furious as there will be no appeals, no lawyers filing endless motions and justice will be swift. If bird bug comes and 1 billion people die worldwide as some say, thats one sixth and a hair of the world population. Thats 50 million US citizens... What do yo think is going to happen to world order? Yesterday the State Department recommended that all HK US expatriates belly up and get three months worth of food, water, medicine. Get the picture guys? Mary, all I can say is that you and others need to be personally responsible for those you care about. We are a reactive society, we are reacting early though. Not unlike white blood cells against an infection. The main body just hasnt caught up yet.

By M. Randolph Kruger (not verified) on 08 Nov 2006 #permalink

Oh, dear. I like you, MRK. But you are so wrong.
You know, there is somebody, a person in every human being. There's someone in you and someones, similarly "I" also in others around you. You can't just atom bomb H5N1 outbreaks or force three-jobs-doing-mothers-of-five to take the fourth minimum wage job and expect none consequence. We are all people, valuale beings. Republican disavowness and negligence about this ethical, moral and psychosocial fact is one of the biggest weaknesses of the Bush administration.

Well, I'm pretty sure MRK is right about the Iran thing. I don't agree with what is going to happen, but if you listen to what Israel is saying ("if you don't nuke em, we will" so many words) we are on the way, collectively wagging the dogs and goosestepping to the not so distant drum beats of war. Same tune as Iraq, slightly different lyrics.
Randy: As regards Flu prep, I spent a few hours today sending emails to all Hawaii state officials (representatives, senators, the governor & lt gov, Board of Education, head of health and human services etc.) again raising the issue of immediately establishing and stocking community preparedness centers. I can only hope they listen. One indication someone in the US Govt might be is found in a handful of recent postings on the Rumors thread at Fluwiki. According to these, the govt has sent some of the larger stores pallets of supplies designated for flu preparedness. Some of the bloggers are nervously taking it as a sign a pandemic is imminent, but I'm hoping it just means the govt finally has started to do something useful and proactive in terms of flu preparation. I guess we'll see. From a personal standpoint, I don't seem to be able to get through to my family about the need to prepare. I feel like my only chance to convince them is via the government. If I can get THEM to act, then maybe my family will take the threat seriously enough to respond. And since most of them live in another state, I have to convince the entire US government - or at least the governments of two states - to act in order to save my own children and grandchildren. What a roundabout crock, eh?

By mary in hawaii (not verified) on 10 Nov 2006 #permalink

ThinL - I have no idea how old you are but I was 50's baby and was one of those people who thought that the world wasnt flat, and that we could do anything together and thats a good part of it. The WE generation became the ME generation. I can tell you that on the dark of the moon, just after Iran either tests a nuke or uses one that the Israelis, the Russians or the Americans are going to be taking them out. There will be no question. I am sure you have seen me comment that the Chinese if our friends the Norkos popped a nuke cap that might wade in there and take them out themselves, they did it pretty diplomatically.

My sources tell me much post of this that now the Chinese pretty much told them that they werent firing anymore nukes, or else. Not so much a military intervention as a economic one. No fuel, no electricity, no food support. Big decision on what to do on the Norkos part.

We dont have that kind of leverage in Teheran. They have changed that tune from producing electricity to producing nuclear weapons. Teheran will be told ONCE and only once to get rid of them and then the decision will be unanimous on the part of the Security Council. Take them out. Its going to piss the Muslim world off, but the sure response of the Israelis will be to hit them themselves if we dont. We can use B-2's, B-1's, B-52's and of course the US NAVy once the triple-A is suppressed but that allows us to keep it conventional. They have only one or two shots and that means we will find out if they are truly a regional nuclear power. Then we have a full blown arms race. We can throttle the Israelis, but they steer their boat in their own interest. They drop a nuke on the near border of Russian and we will see Russians crossing iran within hours in my and some very learned individuals opinion on the way S. Lebanon.

Bird flu might not be so bad after all. There isnt much we can do about the military situation if it starts. We will be committed but again its a foregone conclusion as to what we will do. Just as we ALL knew that we would be going back into Iraq back in the 90's.. The Dems want to partition Iraq. So you get the Iranians into control of the Kharq Island facility and three nations fighting over their own oil. The Kurds will be heads up with the Turks. the Saudis heads up with the Shia's from S. Iraq and funded/supported by the Iranians. And finally you have a 30/.60 something split in Baghdad with pockets of different types of Islamic fundamentalists. Oh, this is going to be fun.

Thinlina, a nuclear strike against a biological disaster has ALWAYS been on the books. They practice for it actually. Before we had the neutron weapon, it was generally agreed that it couldnt be done. But this weapon actually made it "feasible" if thats the word that could apply to swacking a huge area. It just wouldnt have the lasting effects of a high radiation nuke. Its just enhanced radiation is all at the point of detonation. Things would have to be very,very bad for them to do that. A few months ago certain navy's took up postions in the waters off the coast of Indonesia. All were nuclear as well as bio capable. If they were there to help then why not make port? They havent yet and have been at sea for almost three months now. Were they thinking what I was thinking? I dont know. I wouldnt want to think about it happening except in the movies.

Its going to be one hell of a year 2007, that I think we can all count on.

By M. Randolph Kruger (not verified) on 10 Nov 2006 #permalink

MRK, take a deep look in the mirror and tell me what you see. Because looking and reading your letter I don't see a beautiful thing. Happy fathers' day.