bird flu simulator

[nathaniel 0]

clicky

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Simulation of a pandemic flu outbreak in the continental United States, initially introduced by the arrival of 10 infected individuals in Los Angeles.

My advice is to do what your parents did; get a job, sir. The bums will always lose. Do you hear me, Lebowski?

[Lefty 0]

Los Angeles, eh? I noticed the simulation didn't factor in the presence of Jack Bauer...virus dead.

Provoking a reaction isn't the same thing as saying something meaningful.
-Calvin

[kelpdiver 2]

heh - based on those 3 snapshots, I see Bush closing the border to Californa as part of that new special plan. It's not like we voted for him anyway.

[ExAFO 0]

Since I'm too lazy to research it...

Is this flu one of those bugs that prunes away the weakest amongst us (i.e. elderly, infants, immuno-compromised) or is this something of legitimate concern to healthy rank-&-file folk?

Illinois needs a CCW Law. NOW.

[nathaniel 0]

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Is this flu one of those bugs that prunes away the weakest amongst us

Right now it's not contagious between humans, and the mortality rate is estimated at between 1 and 30 per cent. Which is where you get newspapers quoting huge death rates from a pandemic, they only quote the high figure.

It /is/ being found in increasing numbers of different species such as different types of fowl, cats, and pigs too iirc. To date people seem to contract it by inhaling bird poop; most of the people who have come down with it are people who live with birds or people who work with birds. There's some speculation that there may be a large number of people who contracted it but who didn't have any symptoms at all, but there's not much proof of this. Part of the fun is that testing for bird flu is very inaccurate, and a high-end, time consuming and expensive laboratory is required to confirm any results before they can be relied upon...the tests only get done when someone gets very ill or dies. It's believed to have an incubation period of approx 1 week (during which time the victim is contagious but doesn't know it yet), which is about twice as long as regular flu, but once symptoms set in the disease seems to take its course more rapidly than regular flu.

It's spreading rather quickly among wildlife and chicken farms in Asia, Africa, and Europe, and there have been predictions it'll reach North America via migratory birds within a year's time. Although some scientists are convinced that it's poorly regulated and illicit poultry trade that's responsible for the spread instead of migratory birds...really there's not enough evidence to know (yet).

And the best part is that currently there is no vaccine and the vaccines we have for ostensibly similar flu viruses must be used in very high doses to connote any benefit...

WHO Bird Flu Fact Sheet

My advice is to do what your parents did; get a job, sir. The bums will always lose. Do you hear me, Lebowski?

[altichick 1]

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the mortality rate is estimated at between 1 and 30 per cent.

Where did you get that figure? The figures for the H5N1 strain are higher, according to the WHO "Altogether, more than half of the laboratory-confirmed cases have been fatal" http://www.who.int/mediacentre/factsheets/avian_influenza/en/

Don't sweat the petty things... and don't pet the sweaty things!

[altichick 1]

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Since I'm too lazy to research it...

Is this flu one of those bugs that prunes away the weakest amongst us (i.e. elderly, infants, immuno-compromised) or is this something of legitimate concern to healthy rank-&-file folk?

Most of the people who have died have been previously healthy children and young adults. However most deaths have been in people working with infected birds so it could just be that this is the age group / population that has been most exposed.

*If* the virus develops the ability to transmit human to human *and* still maintains its high mortality rate it's going to be a very big concern! But until then there's little point worrying about something you can't do anything about.

Don't sweat the petty things... and don't pet the sweaty things!

[MrBounce 0]

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Since I'm too lazy to research it...

Is this flu one of those bugs that prunes away the weakest amongst us (i.e. elderly, infants, immuno-compromised) or is this something of legitimate concern to healthy rank-&-file folk?

Most of the people who have died have been previously healthy children and young adults. However most deaths have been in people working with infected birds so it could just be that this is the age group / population that has been most exposed.

*If* the virus develops the ability to transmit human to human *and* still maintains its high mortality rate it's going to be a very big concern! But until then there's little point worrying about something you can't do anything about.

I don't have the sources to hand, but this 'flu causes the bodies immune response system to overreact. So people with healthy immune systems are actually at greater risk once they catch the disease. They are harder to cure and tend to die quicker.

So its pretty bad cross the spectrum.

Gavin

Ashes to ashes, dust to dust. If you don't take it out and use it, its going to rust.

[nathaniel 0]

The difference is between what's predicted for a pandemic vs what's estimated of the people who are known to have contracted it so far...I'm assuming most of the risk to the average person is from a potential pandemic rather than from exposure to the current strain, which is clearly more lethal.

I don't think anyone is predicting the mortality rate to stay so high if / when a pandemic were to strike.

My advice is to do what your parents did; get a job, sir. The bums will always lose. Do you hear me, Lebowski?

[brierebecca 0]

I've been to a couple meetings at work (I work for the Department of Health), and some of the doctors in the bureau of epidemiology think that it will mimic the results of the 1918 influenza outbreak - that is, the post above about those with healthy immune systems having the greatest mortality rate is true. I think the way it works is that the immune system overreacts and causes some kind of shock to the system. Those who have these healthy immune systems generally caught the virus and were dead within a day.

Brie

"Ive seen you hump air, hump the floor of the plane, and hump legs. You now have a new nickname: "Black Humper of Death"--yardhippie

[kelpdiver 2]

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the mortality rate is estimated at between 1 and 30 per cent.

Where did you get that figure? The figures for the H5N1 strain are higher, according to the WHO "Altogether, more than half of the laboratory-confirmed cases have been fatal" http://www.who.int/mediacentre/factsheets/avian_influenza/en/

But the only cases they have to confirm are the obvious ones.

[billvon 3,120]

>I think the way it works is that the immune system overreacts
>and causes some kind of shock to the system.

So immunosupressives might have a prophylactic effect? If overstimulation of the nonspecific response is the culprit, then over the counter remedies (antihistamines etc) would seem to be of value in reducing risk.

[altichick 1]

There hasn't been enough research yet to know how many asymptomatic infections are occuring and so an actual mortality rate is hard to determine.

Early studies suggest not that many asymptomatic cases are occuring...This study from The European Centre for Disease Prevention and Control (ECDC)

"No asymptomatic H5N1 virus infections in Cambodia.
From the International Conference on Emerging Infectious Diseases, Atlanta (US)

Dr. Philippe Buchy of the Institut Pasteur in Phnom Penh showed the results from a survey conducted on 351 people from villages where H5N1 virus infection had been detected both in poultry and in humans. Using serology the researchers found no indication of additional infections (asymptomatic or mild cases), despite the fact that many of the selected people had had significant exposure to infected poultry. Among them also several doctors and nurses that have had close contacts with patients. These findings support the views that

1. where there is no poultry immunisation surveillance for H5N1 in humans is probably highly sensitive in South-East Asia
2. that H5N1 doesn’t spread easily among humans and that the case fatality rate is still really very high (more than 50%). "

Don't sweat the petty things... and don't pet the sweaty things!

[kelpdiver 2]

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There hasn't been enough research yet to know how many asymptomatic infections are occuring and so an actual mortality rate is hard to determine.

that's the point.

It's hard to prove a negative. Sometimes it's hard in terms of time and money, other times it's simply impossible.

[Michele 1]

Something seems to have happened this spring in terms of H5N1 spreading; over 30 new countries in the past few months have reported infections in their avian population, both domestic as well as wild. Prior to this, there were only 15 countries that had confirmed it's presence. Yahoo News.

Further, in mid-March, Michael Leavitt, Secretary of Health and Human Resources, suggested that the American public start preparing for shortages by buying tuna and powdered milk and storing it under the bed. While that is reminiscent of "duct tape and plastic", and may indicate some sort of fear mongering going on, I'm not sure what to think about it, and not willing to dismiss it out of hand. I do tend to be prepared in any event, simply because I live in earthquake territory, but still...this is curious. ABC News. I don't have powedered milk, however...

On April 1st, Bush added Avian flu to the list of communicable diseases for which the military is authorized to quarantine. Here is the ammendment. Some thought that this was an April fool's joke, as did I at first...but I am not sure it is, any more. 'Course, it might be, and I've missed the clues. If so, please feel free to correct me...

As a passing note of interest, one town in Romania has already been quarantined because of the avian flu. Cernavoda, Romania. I'm not sure what happened to the town, as I haven't been able to find follow-up articles about it.

On another note, from what I've read, H5N1 has spread its species carriers to include dogs, cats (large and domestic), minks, ferrets, pigs, and other mammals. It is suspected to have infected some penguins and killed in Antartica, as well. While this itself poses a problem, the severity is increased simply because the more vectors a host has, the more potential it has to mutate to the human to human virus.

Two last notes; the results of the recent trials for the vacine were underwhelming, to say the least, and the Gaza Strip bird owners are saying "pay us before we kill the chickens..." to the Israeli government. IOW, the infected birds are not being killed prior to extermination unless there is payment in hand. This could be a problem.

The potential for this flu to change the way of life for many many people is there. It already has; the poultry industry has been hit hard in many countries, and people who depended upon the poultry industry have been slammed economically. Further, importation and exportation of chicken and turkey has been stopped in many places, to prevent/slow the flu's progression. The potential is huge for it to create both economic as well as health crisis is enormous.

Just thought I'd throw those things into the pot...

Ciels-
Michele

~Do Angels keep the dreams we seek
While our hearts lie bleeding?~

[nathaniel 0]

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So immunosupressives might have a prophylactic effect?

FWIW the WHO article I linked mentions that leukopenia has been a symptom...making me wonder whether immunosuppressives are indeed a bright idea. I'm a complete layman tho, so really I can only speculate. Science may tell...

My advice is to do what your parents did; get a job, sir. The bums will always lose. Do you hear me, Lebowski?

[kelpdiver 2]

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Something seems to have happened this spring in terms of H5N1 spreading; over 30 new countries in the past few months have reported infections in their avian population, both domestic as well as wild. Prior to this, there were only 15 countries that had confirmed it's presence. Yahoo News.

But maybe not too surprising. I read recently about how a fantastically large number of birds all migrate up and down Euro-African continent through some pretty tiny throughfares in Israel. (see, it's the JEWS!)

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On April 1st, Bush added Avian flu to the list of communicable diseases for which the military is authorized to quarantine. Here is the ammendment. Some thought that this was an April fool's joke, as did I at first...but I am not sure it is, any more. 'Course, it might be, and I've missed the clues. If so, please feel free to correct me...

Bush working on a Saturday!? Oh, that was actuallly April 1 of 2005. A Friday.

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Two last notes; the results of the recent trials for the vacine were underwhelming, to say the least,

I had heard more favorable impressions here - 40-50% of the trial subjects showed increased immune response. For an epidemic, that sounds like a carbon rod being put into the reactor. And it could get better, depending on how much of a moving target it is.

[Michele 1]

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But maybe not too surprising. I read recently about how a fantastically large number of birds all migrate up and down Euro-African continent through some pretty tiny throughfares in Israel. (see, it's the JEWS!)

(LOL! at your jew comment. Sadly, though, some people will believe it's their fault...)

The difficulty I have with your position is simply this...while it may not be "surprising", it is alarming. This particular flu was identified in 2001, iirc, and culling of birds began then. However, it was in the wild bird population...but that doesn't explain how it didn't "bloom" like this until this year. Unless, and I'm no statistician, there is a quantitative factor, such as when 1 bird gets it, gives it to three others, 2 die, the two still alive infect another 6, and so on...sort of like the exponential Alpha Beta commerical from years ago. I can see how that would've built up into a "bloom" thing, except I don't see how it would've taken 5 years to do it. Wouldn't we have seen small outbreaks in other areas from the migratory birds earlier than this? Unless it's mutated and able to live longer before killing it's hosts...which could pose one helluva problem.

Maybe I'm missing something with that, though...can anyone correct my thinking?

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I had heard more favorable impressions here - 40-50% of the trial subjects showed increased immune response. For an epidemic, that sounds like a carbon rod being put into the reactor. And it could get better, depending on how much of a moving target it is.

Let me look into it; I read a report somewhere that made it seem much less effective than 40%, but I could've misunderstood what I was reading. I'll come back with more info, either corroborative or contradictory.

Edited to add: Kelpdiver, you were right in your estimate on the numbers, however, the "underwhelming" aspect is that it showed elevated antibodies in just over 50% of the patients when used at the strongest dosage and boosted (i.e. a second shot several weeks later). The normal flu vaccine is somewhat more effective, with a one shot dose, coming in at something to the effect of 70-80% of the people. Here's the article I read on it, which made me think less highly of the vaccine than you have. ABC's story. Thanks for having patience...

Ciels-
Michele

~Do Angels keep the dreams we seek
While our hearts lie bleeding?~

[nathaniel 0]

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Something seems to have happened this spring in terms of H5N1 spreading

A major reason for that is that bird flu is seasonal, much like the common cold and west nile. Bird flu is expected to peak around this time of year, iirc.

My advice is to do what your parents did; get a job, sir. The bums will always lose. Do you hear me, Lebowski?

[ExAFO 0]

Meh, what the hell is getting worried about it gonna do? Just get a flu shot and don't french kiss a pigeon, gull, or Canadian.....(goose).

Illinois needs a CCW Law. NOW.

[Michele 1]

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A major reason for that is that bird flu is seasonal, much like the common cold and west nile. Bird flu is expected to peak around this time of year, iirc.

(as I sit here nursing either the flu or a good, heavy cold...)...

I agree in principle, but am curious as to why *this* year rather than years past. This particular flu was identified in 2001...and I just don't get why this year there's been such a spread as opposed to last year, or the year before. I am not saying that the spread is unnatural, or that anything nefarious is going on; I am positive that there is a scientific reason for it...I just don't know it. I suspect it was sort of a tipping over of infected birds and their migratory patterns, due to an exponentially higher infection rate for whatever reason, but I don't know. And that's what I'm curious about. If it went this far this fast this year, what should we expect next year?

Ciels-
Michele

~Do Angels keep the dreams we seek
While our hearts lie bleeding?~

[billvon 3,120]

>I agree in principle, but am curious as to why *this* year rather than
>years past. This particular flu was identified in 2001...and I just don't get
>why this year there's been such a spread as opposed to last year, or the
>year before.

Mathematical reasons. It is exactly this sort of geometric expansion that makes pandemics a problem, and is why there was much hubbub about it in 2001.

>If it went this far this fast this year, what should we expect next year?

Precisely.

>. . . the Gaza Strip bird owners are saying "pay us before we kill the
>chickens..." to the Israeli government. IOW, the infected birds are not
>being killed prior to extermination unless there is payment in hand. This
>could be a problem.

Indeed. It's one of those "$1 to cull a flock equates to $10 to cull a flock the next year, $100 to kill wild birds the year after that, $1000 to treat a family that caught it" sort of things. We could have stopped this thing in its tracks by culling every single bird suspected of the disease four years ago, but unfortunately we didn't. The price will now be a lot higher.

[kelpdiver 2]

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Edited to add: Kelpdiver, you were right in your estimate on the numbers, however, the "underwhelming" aspect is that it showed elevated antibodies in just over 50% of the patients when used at the strongest dosage and boosted (i.e. a second shot several weeks later).

Right, I recall that now. The dosage was substantially higher than would be practical on a wide scale.

Still, as a stepping stone, it's worth something. You look at how long people have been working on HIV vaccines with nothing tangible so far. (yeah, it's a much harder task) To get this far this quickly gives me optimism that this threat will end up substantially less disasterous than its 1919 grandfather.

[nerdgirl 0]

Hmmm, the press release notes R0 without fully explaining how important that part of the model is.

R0 is a measure of how effective an infectious disease is transmitted. It's very important in constructing meaningful models.

If R0 is less than zero, one person infects less then one other person -- the disease does not spread. Getting an R0 of zero is a combination of the characteristics of the bug and the success of public health intervention efforts (vaccination, quarantine).

If R0 equals 1, 1 person infects 1 other person.

If R0 is greater than zero, than the infection can potentially be exponential.

Currently the R0 for human infection of H5N1 is much less than 1. Speculate that these researchers used a value from 1917-1918. That may be reasonable or may not.

By comparison, the R0 for the 1957-1958 pandemic “Asian flu” A (H2N2), for which there no vaccine, was 1.7.

Measles pre-vaccine R0 was 14-18.
Polio is 5-7.
Tuberculosis is 2
Ebola is 1.34 - 1.8.
AIDS is 0.34 - 1.5
ppneumonic plague is 0.8 - 3.0.

The choice of too low an R0 value will yield a model in which disease spread is unrealistically slow and may give a false sense of ease of response and disease control. Conversely, if a selected R0 value is too high, an equally unrealistic scenario will result, which overly weighs the threat of one agent.

I'm interested in what R0 they used.

marg

Act as if everything you do matters, while laughing at yourself for thinking anything you do matters.
Tibetan Buddhist saying

[Michele 1]

Bird Flu in Scotland...

A swan that was found dead was tested and preliminary results show positive for H5. Confirmation is expected tomorrow.

Kelpdiver, I agree with you that there is reason to be optimistic; and that steps have been taken to produce a vaccine that will work...and that it is much harder than an AIDS vaccine...but it's still worrisome a bit (at least to me.). I hope they get it worked out in time, know what I mean?

Ciels-
Michele

~Do Angels keep the dreams we seek
While our hearts lie bleeding?~