[ARCHIVED THREAD] - Pandemic planning (Page 1 of 2)
Posted: 6/16/2008 7:24:19 PM EDT
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I have been a member here for a while, but don't cover the SF forum everyday. I know SHTF can be a multitude of scenarios. Do most of you know that the Fed. Govt is planning on an influenza pandemic over the next 5-10 yrs? The H5N1 virus has officially combined with the H3N2 common influenza virus in the lab to make the deadly Avian flu virus communicable human to human. Any idea what kind of contingency plan the govt has? I can guarantee you it is not pretty. The feds are not planning to help. All local govt and facilities are on their own as far as resources are concerned. If your local authorities do not plan for this and anticipate it, it will be very bad for anyone in that area. It is going to be bad anyway, but planning will help. The basic survival mindset is the main thing. Those that rely on others to help can pretty much guarantee their own demise. Those that bug in to their planned locations with a month or two of supplies will come out pretty good, and in a whole lot less populated area than what they remembered it being before. |
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The actual govt. plan can be found on the Dept of homeland security website. Also check your state .gov website for their plan as well. The Fed plan is a strategic outline for all of the states to follow. They will have limited resources and 99% of the population will not be ready. You however have have taken the first step by acknowleging there is a potential problem. Now, Don't panic. There is still time to educate yourself about a Pandemic. They have happened throughout history and will happen again. Most scientist say we are due and H5N1 has potential to be the one. BUT there are other flu virus types out there that could just as easily be the one. Look into the H7 type viruses. You have Ebola, MRSA, TB, and a few others that could spin out of control. Acquiring knowledge about Pandemic potential viruses is the most important step in preparing for them. The are some great websites devoted to Pandemic flu. FluWiki is the best one I have seen and you can get most of the info you need. AccurateOne |
| im a banker and we were required by the fed to create a pandemic plan/policy that will be reviewed at our next examination. most of the bank employees took this as a joke i.e. last man standing take the money is what they liked to say. not my job to educate them i guess and due to my fore thought and planning, i figure i would be the last man....... |
a month or so back there were some articles in the main stream media reporting computer simulations the .gov did regarding the spread of a virus. the .gov's plan was to quarantine the infected neighborhood/city. the computer indicated that quarantining would stop the spread at epidemic levels and prevent a pandemic. good luck w/ that quarantine when the sheeple's food runs out.
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I am on the committee. The Fed govt has the websites as AccurateOne stated. I don't have all the info with me, and we are still trying to get as much accurate info together before putting together a public information packet for our county. The quarantine may work in theory, but with most of the sheeple thinking they are more important than everybody else and controlling the outbreak, I just have my doubts most people would stay quarantined for more than a day. The plan calls for about a two week period of quarantine.  Good luck stopping people from going to the store and trying to buy something. That is why in a pandemic, the CDC has the authority to shut the businesses in an area down for whatever length of time deemed necessary to control the situation. |
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Here is a great information video you can watch online, they used to send out free copies on DVD, seems like they ran out. Business Not As Usual: Preparing for a Pandemic Flu link Enjoy |
You really need to back up statements like this with sources that are real as well as peer-reviewed (preferably). Sure as hell don't point us to a Wikipedia entry. This sort of statement needs spell checking as its H5N1 but nonetheless: The HN51 virus has officially combined with the H3N2 common influenza virus in the lab to make the deadly Avian flu virus communicable human to human. needs some sort of support independent of your own claims. Do you have a CDC source or NIH reference or perhaps a WHO report? |
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H3N2 + H5N1 would be bad juju. Sadly one or two mutations it could be real. A protein here and there and boom,,pandemic. I have searched for any news of the combo and have not read anything new. And BTW, the shelter in place planning speaks of weeks and months, not just 2 weeks. When the officials I thought had all the answers told me, if a pandemic happens YOU better have your shite' together, it grabbed my attention. Theirs is simply NOT ENOUGH resources to handle a large scale pandemic. |
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www.fluwikie.com This is a great starting point to the basics about Pandemic Flu. Dr. Michael Oosterholm is a very respected scientist who has been very outspoken when it comes to a Pandemic. As far as the OP's comment about H5N1 and H3N2 combining I haven't seen anything to confirm that. I know that there are some scientists who have been trying to guess what H5N1 is going to do next. They have been trying to find out what would be the right combo to make H5N1 Pandemic capable. I would assume they have tried to combine the top suspect combinations in the lab by now. There are plenty of good reference points on the web. The basic science is pretty easy to understand for most anyone. Just basic science and biology class. If you understand the basics then that will help you look for the bubbles in the Pandemic pot. There are people all over the world who are watching this. We will know on the web way before we get any confimation from any government or agency. Indonesia has officially stopped reporting H5N1 deaths. Myanmar has never oficially reported a death yet they are next to Indonesia. The financial ramifications to a country with widespread high path H5N1 can be and has been financially devastating. No country wants to be the one where the pandemic boils over. AccurateOne |
link this not a field that i am at all familiar w/, but the article seems to support what eng208 stated. edit: more info, specifically info on research article discussed in above link.
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Look, noone wants to be the person that put this out on the web. I probably should not have mentioned it. I just wanted to put the awareness out there that this is a very real probability. As for my source, like I said, I am on a planning committee and my source is a representative of the state health organization. Look at my state if you must  You might get better results and less defensiveness from people if you change the attitude that your writings reflect. And while you are ridiculing me for making the mistake of hitting the N before the 5, you need to capitalize the N in Need at the beginning of a sentence after a period. |
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Thanks eng208 for sharing the info you had. I follow H5N1 somewhat close and I had not seen the test report. Don't let people get under your skin here. Just keep your eyes and ears open for any news. It seems you may be in a position to get some good info. I for one do appreciate it. Knowledge is power and because of your first post I will be digging into the test results and bouncing them off of some of my contacts. Thank You! AccurateOne |
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If the government was admitting that H5N1 and H3N2 had mutated into a single flu strain that was communucable to humans, not only would we have heard of it before this, but it would be here already. Something like that would spread accross the globe like wildfire. |
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I think what the article says above is that when they made possible combinations in the lab that 50 of those combinations did not prove to have Pandemic potential. However, 28 of the combos did have Pandemic potential. Many scientists say the traits that H5N1 needs to acquire will make it less deadly. The problem is that the high death rates happening in some countries is way high. Indonesia and Vietnam rates have been higher than 65% death rate in confirmed cases. Even if H5N1 does become less deadly and say it has a sustained death rate of say 10% then the world as we know it will change during and after a Pandemic. In 1918 the fatality rate was only like 2%. Even at that rate today you would be talking about 10's of millions dead. If H5N1 was boiling in a modern country like the US then it would be easier to monitor. One of the biggest problems with H5N1 now is that it is bubbling away in these 3rd world countries that do not have a solid medical infrastructure or agriculture system. If and when H5N1 or any pandemic potential virus boils over .gov will be way behind. The chances of stopping it at any border in SE Asia or China will be virtually zero. There is up to a 3 day incubation period with H5N1. People will be walking around infecting other people for many days before any govt knows what is happening. The next Pandemic virus will be on the next plane out and then we will have exponential spread via the airlines. Build your preps, make a plan and acquire as much knowledge as you can about the threats that face us. "The Great Influenza" by John Barry is a great read. AccurateOne |
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Pandemic is man made, assisted and is coming soon. Nobody is going to like what the aftermath holds in store. Read about what Celeste Bishop has to say about pandemic here in the US. She has worked with emergency management in a high slot federal (fema) level, state level and local level. Anyone want info on the subject, visit her site. It has more info than one could possibly only wish for. I have also listened to her live in several interviews. She is privy to most all the government "Plans". She in turn makes that info available to you. 
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the .gov is not admitting that H5N1 and H3N2 mututated, what they are admitting is that they are attempting to combine it to see how likely it is that the two will combine. |
Pandemics are not man made. Pandemics happen naturally and have occurred frequently throughout history. The Pandemic of 1918 happened before modern medicine. In fact it is because of that Pandemic that our medical knowledge increased exponentially in this century. Biological warfare can happen. Not many countries out there want to unleash an Ebola or or even a Flu Virus because they cannot control it. AccurateOne |
So your saying this is a planned event!! That will be hard to prove..depopulation at it's finest, and plausible to say the least!! |
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fluwikie.com is not part of the wikipedia network. It is a site much like AR15.com. It is a knowledge base for people looking to learn more about H5N1 and other strains of Influenza. I am not affiliated with them at all. The forums are frequented by many scientists and they can answer most any questions you have. The people who run the site rub elbows with all of the top scientists and .gov reps. If you want to learn about Pandemic Influenza this is a great starting point. The scientific articles are broken down into laymens terms. They have an excellent survival network and many great ideas that they share. I have learned many things about prepping the home for medical emergencies. Spend some time there if you want to learn more about Pandemic Influenza. The first page has a link to getting started with H5N1. AccurateOne |
 That is not what I was saying. I am saying that the govt. has speculation that this will occur in the future, based on lab testing of the mutation of the H5N1 virus. If, or when it happens, then the population that has not taken steps to make plans for the event will not find assistance from the fed govt due to the lack of resources to handle a nation or most likely a worldwide pandemic event. With international travel and an incubation period of 2-3 days, then a surface life of a couple of days, (meaning the virus from an infected person that touches a door knob, telephone, or any of the thousands of surface contacts we make), the spread would be so fast and so effective that few would be left to take care of the situation. The old would almost automatically be written off, many of the young would also succumb to the virus. The only solution to keep yourself well or overcome the virus is a well taken care of immune system, lots of fluids, wash hands with good soap, and keep yourself away from other people.I made no reference to a conspiracy of population control.
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Ok! The whole fucking with it in a lab threw me off. And someone will prolly turn the shit loose anyway... |
BS on the red. While there has been at least one confirmed human to human transfer of the virus, it's hardly there yet. And a combination of those two would most likely result in a virus that is less virulent than H5N1. Its still something to be concerned about, but we have almost a year before we need to even worry about it again. I've done stuff with FEMA, I've done the CERT stuff and yes, if it DOES happen as bad as everyone thinks it will (which it won't), FEMA/.gov isn't going to be able to do squat. |
This statement is not quite on par with the science that is out there. When someone is infected with H5N1 the body immediately starts to fight it. Your body starts what is called a cytokine storm. The influenza virus is constantly infecting new cells within the lungs. Your body has to kill the cells to kill the virus. This ovewhelming response actually destroys your lungs. Many people who survive H5N1 eventually die of pnuemonia or other respiratory diseases. Encephalitis was another major cause of death during the 1918 Pandemic. If they do live they are never the same. Now back to the cytokine storm. In the Pandemic of 1918 the majority of the people that died were young healthy adults. There were fewer deaths in the very young, babies and elderly. The reason is because their immune systems were less developed or less healthy. Therefore the cytokine storm produced by the body was less severe and less damage done to the lungs. Social Distancing is the key to surviving a Pandemic. Until 1918 shaking hands was the formal way to greet someone. Once people learned that the virus spread through contact gentlemen started tipping their caps. The 1918 Pandemic hit in four 6-8 week periods. It came and went in waves. Unfortunately, no one knew when the wave was coming so if you guessed wrong on the day to go to church or the market you probably didn't come home. Anyone heard of the kids game Ring around the Rosy? That started during the 1918 Pandemic. The stench from rotting bodies waiting to be buried and the fires that burned the bodies was so strong that people carried around a pocket full of posies to put over their face. The ashes, ashes we all fall down part was the ash from the death funaces spreading in the air. The we all fall down part means you were dead..............My kids do not play this game! Guys the science behind H5N1 isn't hard to understand or find. You will be better prepared if you will take a little time to do a small amount of research. Not knocking anyone just concerned for my fellow man. Someone posted that we do not have to worry about it until next year. Not true. H5N1 is a disease in migrating birds. They can and have carried this desease to over 1/2 of the earth. The crucial mutation may be waiting for them on a lake in China of in the middle of Africa we do not know. The birds never stop moving. SE asia has been the hotspot. Egypt concerns me greatly. The birds brought the hot form of H5N1 from Quinghai Lake, China and introduced it into N. Africa. The disease seems to be very bad there. If that goes further south into Somalia and other shit hole countries it could get bad very quick. AccurateOne |
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something you guys need to keep in mind. most of these scientist live off of grant money. while there is good valid information there, there is also a bit of fear mongering used to get them research/grant money to stop the next pandemic. i watched this on a regular basis by researchers at usamriid. yes it's possible but read this stuff with a bit of this in mind. |
+1k Whether it's bird flu, global warming today or the coming ice age of forty years ago, there's a lot of money to be made in "hard science." |
True enough. But let's take ebola for example. Ebola kills its host to quickly therefore it burns out very quickly. If ebola was able to infect birds but not kill them then I would say that one may be the apocalypse. A human killer with the ability to spread across the globe. But, in its current form ebola is to efficient. Influenza viruses are different in that they can adapt to different hosts. The virus is actually looking for its nirvana, a host in which it can live in harmony. Yet, they change because they become intermingled with different types. If we were able to seperate all of gods creatures and keep them that way then the Influenza viruses could find a compatible host and thrive. However, since that isn't possible Influenza viruses will continue to exchange proteins and alter their own DNA to keep seeking its perfect host. There are other diseases out there that are worrisome. If H5N1 doesn't become a Pandemic strain then there will be another right on its heals. H7N2 could be the next candidate. The new Super TB, MRSA and a few more are out there and we will be dealing with them soon enough. AccurateOne |
I agree with you. I am one who believes about 10 percent of what I read. H5N1 is a little different. 1. Pandemics happen 2. We have an Influenza virus that has jumped to humans and kills humans very effectively. 3. Has shown the ablity to be passed from human to human. Although not very effectively yet. 4. Has jumped to multiple species and therefore can pick up more traits from other mammals. Not all Influenza viruses can infect cats and weesels. This one has. The jump to cats was a trigger point for many scientists. The more mammals it exchanges proteins with the more of a chance H5N1 picks up the necessary mutations to easily pass between humans. AccuarateOne |
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AccurateOne, you seem to be very well educated on this type of problem. I am just beginning. You are correct on the way that the virus attacks the host and the immune response. The problem with the old is that most older patients have chronic respiratory problems to begin with. The additional stress that a serious form of the flu places on them is many times unbearable and exacerbates an underlying compromise. Compromise the respiratory system too much and you have respiratory failure, leading to death. The problem with kids results from the metabolic activity of a normal kid is such that the respiratory system is so important of getting rid of the carbon dioxide from the cells in the body. That is one of the reasons a kid has a faster respiratory rate than an adult. Another is the size of their lungs being of course smaller. Compromise the ability to get rid of built up CO2 and the body becomes acidotic, which can result in kidney failure, liver failure, and the body can not survive acidosis long term. Also dehydration plays a huge role in the mortality/morbidity rate of infected individuals. The adults that do survive often time have ARDS. Adult (sometimes called acute) Respiratory Distress Syndrome that makes them short of breath and remodels the lungs to where they become much less efficient. I would like to meet you one day, I am sure we could discuss many interesting things.  As for Rkclmbr that referred to "BS to that in red". I don't really care whether you "think" it is BS or not. Just because you read it on the internet does not necessarily make it true, but just because you can't find it on the internet does not mean it is BS either. If it is BS, a pretty good source from the state is spreading it
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re: your calling BS on the red, you're actually wrong. go read the long post i made on the first page where i actually link to a study where they did indeed combine H5N1 and H3N2 w/ varying degrees of success. |
sorry for the triple tap - this forum really needs a multiquote function.
agreed. what i worry about is that in the name of preventing or, better said, "studying" the likelihood of the combining of the two viruses, man gives the whole process a boost. in other words research to prevent/investigate the probability of a pandemic actually leads to said pandemic. of course i trust that there are a ton of safety protocols to prevent a release of the deadly mix, i also believe whole heartedly in the law of unintended consequences. |
One thing to keep in mind is that dismissing something as doomsday-saying does not invalidate the warning. If you've worked at USAMRIID you know that millions of dollars are spent each year for the bio-terror agent detection and identification systems. I work at Idaho Technology, which has the JBAIDS contract, and understand what the cash looks like. This is millions of dollars being spent for a mostly negative world. H5N1 has been proven to be spreading. Hopefully it stays in the mostly negative realm, yet the same attention at the same intensity isn't being paid to H5N1. I've met people at AFIP and WRAIR that believe H5N1 is a threat and more attention needs to be paid to it. These are also people who don't have grants that they've put in regarding H5N1. Last time I was at AFIP there was only one researcher who expressed interest in Idaho Tech's H5N1 PCR assay on the JBAIDS for field surveillance in the Eastern Block Countries. Also, something must be said about the speed in which the FDA approved the H5N1 vaccine. Reading the study report one could show that previous vaccines had better rates of sero-conversion, with stronger responses, and were still turned down. The vaccine had a lot of time put into it and also lots of $$$. Someone saw enough of a need for something that may never materialize. Why don't we have the same stock piles of vaccines for Ebola, Marburg, VEE, WEE, EEE? Yet the CDC has ~193 million doses of the Vaccinia virus vaccine stockpiled. |
eng208: I will be the first to admit that I am not a scientist or in the medical profession. It seems that you may be more trained than I when it comes to the respiratory system. I am willing to, and need to learn more about it. Maybe you can help me learn more about why the Pandemic strain in 1918 killed fewer children and the elderly. i have always read that it was a lower cytokine storm response by the body. If i am wrong then I would be interested in the correct info. Thanks for starting this thread. AccurateOne |
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eng208: Just went on to fluwikie.com Left side of page: Influenza Science Left side of page: Epidemiology Middle of page: Demographics of H5N1 Demographics of H5N1 in Indonesia Demographics of 1918 virus This data shows that the young are susceptible to H5N1 just not as highly as 20-40 year olds. The curve goes way down at 40 and beyond. Something interesting is that in Indonesia it seems that there has been only 1 out of 57 to die in the 40+ age group. That would put 40 year olds alive before the last Pandemic of 1968-69. Maybe people alive in Indonesia prior to 1969 show some immunity to H5N1? AccurateOne |
Gee, thanks. You mean 'Kook' stuff like the weather wars taking place right now between China and the United States? Nicola Tesla was no kook. That kook stuff is gonna take a few by surprise. Celeste claims, through documents she has uncovered and viewed across her desk while at FEMA level that things will get very interesting, very soon. Many will be forced to make a critical choice or choices. The food supply is to be used in a certain way to achieve a certain result. Pandemic will be used as a cover to advance certain other things and programs. That's why I say this pandemic has a human hand in it. There is only one reason to exhume and splice 1918 to H5n1. You'll see. |
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That is really interesting. It may hold some truth in the belief that most all of the current strains are derivatives of the 1918 flu. If the body has some immunity to the core virus, or at least recognizes it early and acts appropriately it may help prevent the 1918 reponse where the lung cells (the alveoli) basicly ruptured from all of the fluid that was brought as an immune response after the virus had a good start in the body. I think that is what caused the rapid decline in health that ocurred overnight and the pink frothy sputum that led to the demise of many of those flu victims. I have been unable to find any good research that shows WHY the old and young fared better than the middle age people, but the statistics show they did in that particular outbreak, which was unusual. I have looked, but I cannot find what makes the 1918 and the H5N1 strains so deadly to otherwise healthy individuals and the older fair much better, which is completely opposite of normal influenza outbreaks. |
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i am not dismissing this at all. i am however asking you guys to keep a skeptical eye on what is "reported." we have a much higher chance of a tb or "x" pox epidemic than we do bird flu. mother nature has a long history or "cleaning the planet" every few hundred years. the average man on the street is NOT going to be able to stop it, nor will you be able to realistically prepare/ quaranteen yourself from it. by the time you have been made aware it's in your area, your either exposed and on your way down, or your exposed and not symptomatic. either way there is VERY little one can do to prep for such things barring living in a bubble 24x7. i simply do not worry about things i simply can not contain and control. the chances of getting hit by a tornado or earthquake are FAR higher than anyone here contracting birdflu in the next 5 years. |
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I don't care about what you think I "think" as well. I'm a senior in microbiology, and as such have taken several virology classes. The university I go to also has one of the largest Select Agent library's in the world. Now, they may have perfected it in the last month or so, but during the last seminar I went to (May), H5N1 had combined with H3N2 (as well as several others), but does not a perfect combination. The new strain is MORE virulent than your common flu, and transmission is good, but it's not like they've made it as bad as everyone thinks it could go. Like I said, maybe they have done it, but they hadn't as of a month ago as far as the person speaking at my university knows. It's possible they've finally done it. I just want proof. If it's been done to the level that the OP stated, it would make scientific news world wide, and I haven't heard anything. |
| How would one go about preparing for weaponized h5n1 variants hitting the scene? That would throw a wrench in a few plans, huh. Everyone that has the means is working on weaponizing it. Certain critters have been known in the past to 'leak' out into the real world. |
Genetic Compatibility and Virulence of Reassortants Derived from Contemporary Avian H5N1 and Human H3N2 Influenza A Viruses Li-Mei Chen#, C. Todd Davis#, Hong Zhou, Nancy J. Cox, Ruben O. Donis* Influenza Division, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America Abstract The segmented structure of the influenza virus genome plays a pivotal role in its adaptation to new hosts and the emergence of pandemics. Despite concerns about the pandemic threat posed by highly pathogenic avian influenza H5N1 viruses, little is known about the biological properties of H5N1 viruses that may emerge following reassortment with contemporary human influenza viruses. In this study, we used reverse genetics to generate the 63 possible virus reassortants derived from H5N1 and H3N2 viruses, containing the H5N1 surface protein genes, and analyzed their viability, replication efficiency, and mouse virulence. Specific constellations of avian–human viral genes proved deleterious for viral replication in cell culture, possibly due to disruption of molecular interaction networks. In particular, striking phenotypes were noted with heterologous polymerase subunits, as well as NP and M, or NS. However, nearly one-half of the reassortants replicated with high efficiency in vitro, revealing a high degree of compatibility between avian and human virus genes. Thirteen reassortants displayed virulent phenotypes in mice and may pose the greatest threat for mammalian hosts. Interestingly, one of the most pathogenic reassortants contained avian PB1, resembling the 1957 and 1968 pandemic viruses. Our results reveal the broad spectrum of phenotypes associated with H5N1/H3N2 reassortment and a possible role for the avian PB1 in the emergence of pandemic influenza. These observations have important implications for risk assessment of H5N1 reassortant viruses detected in surveillance programs. Author Summary The influenza pandemics of 1957 and 1968 were caused by hybrid viruses consisting of a mixture of human and avian influenza genes. The introduction of avian genes resulted in a sudden change of the virus surface antigens, allowing its worldwide spread due to lack of immunity in the population. The highly pathogenic avian influenza H5N1 virus has continued its spread in domestic and wild birds in Asia, Europe, and Africa. Although H5N1 infection in humans is rare and person-to-person transmission is very inefficient, the steady accumulation of human cases has raised concern over the possible reassortment between H5N1 and human seasonal influenza resulting in a virus with new surface antigens and pandemic potential. In this study, we used recombinant DNA technology to generate a systematic collection of hybrid viruses (with genes from human and avian viruses) bearing H5N1 surface antigens and analyzed their properties in cell culture and in mice. The H5N1 hybrid viruses revealed a broad range of viability and multiplication capacity in cell cultures. In addition, several H5N1 hybrid viruses were highly virulent in mice. Results from this systematic analysis provide important insight to support risk assessment of reassortant H5N1 avian influenza viruses. Citation: Chen L-M, Davis CT, Zhou H, Cox NJ, Donis RO (2008) Genetic Compatibility and Virulence of Reassortants Derived from Contemporary Avian H5N1 and Human H3N2 Influenza A Viruses. PLoS Pathog 4(5): e1000072. doi:10.1371/journal.ppat.1000072 Editor: Adolfo Garcia-Sastre, Mount Sinai School of Medicine, United States of America Received: February 21, 2008; Accepted: April 15, 2008; Published: May 23, 2008 This is an open-access article distributed under the terms of the Creative Commons Public Domain declaration which stipulates that, once placed in the public domain, this work may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. Full study here: http://www.plospathogens.org/articl...ED8A83268E05350 |
Here it is again in plain english: June 1, 2008 Study shows hybrids of bird flu, human flu viruses fit well By Helen Branswell, Medical Reporter, THE CANADIAN PRESS TORONTO - An experiment mating H5N1 avian flu viruses and a strain of human flu in a laboratory produced a surprising number of hybrid viruses that were biologically fit, a new study reveals. And while none of the offspring viruses was as virulent as the original H5N1, about one in five were lethal to mice at low doses, showing they retained at least a portion of the power of their dangerous parent. The work suggests that under the right circumstances - and no one is clear what all of those are - the two types of flu viruses could swap genes in a way that might allow the H5N1 virus to acquire the capacity to trigger a pandemic. That process is called reassortment. "This study is just showing exactly that: There is a risk this virus can successfully reassort with a human virus," said Richard Webby, director of the World Health Organization's collaborating centre for influenza research at St. Jude Hospital in Memphis, Tenn. "The problem is we don't know at this stage whether there's a benefit to these H5N1 viruses in doing that." Nor can anyone say why, if the viruses swapped genes so readily in the laboratory, that hasn't seemed to have happened in the parts of the world where H5N1 has been circulating for years. "This is the million dollar question," says senior author Dr. Ruben Donis, of the U.S. Centers for Disease Control's influenza division. Reassortment is one of two ways in which a pandemic virus can evolve. The other is for a bird virus to acquire a number of mutations that allow it to more easily infect people and transmit among them. The latter, called adaptive mutation, is thought to be the way the 1918 Spanish flu virus emerged. The viruses responsible for the milder pandemics of 1957 and 1968 arose through the mixing of human and avian flu virus genes. This work, done at the CDC, was conducted to study the reassortment potential of H5N1 and H3N2 viruses. H3N2 is one of two human influenza A viruses that cause disease during flu season. The study was published in PLoS Pathogens, one of the Public Library of Science journals. Reassortment studies can be done one of two ways. One involves simultaneously infecting cells with the two viruses and seeing what nature produces. The other involves making viruses by piecing together combinations of synthesized human and avian genes. "It's like Lego," Donis, head of the molecular virology and vaccines branch, says of this approach, which was the one used for this study. But this is a game of Lego where it's not clear from looking at the pieces which will go together into a structure that will hold. "We really don't understand the rules of engagement for playing the Legos. We don't know what makes these things connect well or not connect well," he admits. The researchers created 63 viruses representing the various potential combinations of human and avian internal genes, using an H5N1 virus that circulated in Thailand in 2004 and an H3N2 virus recovered in Wyoming in 2003. All but one of the hybrids carried the hemagglutinin and neuraminidase genes - the H and N in a flu virus's name of H5N1. The remaining one used the neuraminidase from the human virus, creating an H5N2 virus that grew virtually as well as the H5N1 virus and was almost as lethal in mice. Once the viruses were made they were placed in a medium to see if and how well they grew. Viruses were then harvested to use to infect mice, to test for virulence. While 13 of the hybrid viruses either didn't grow or barely grew, the other 50 grew to some degree. And 28 replicated nearly as well as the original H5N1. Donis admits he was surprised by how well the avian and human gene combinations performed. "I was expecting more incompatibility," he says. By studying the combinations that succeeded and failed, the scientists were able to start to see patterns of which gene combinations are critical for an H5N1 virus to thrive. When the most viable viruses were tested in mice, none was as nasty as H5N1. "That's the good news," Donis says, alluding to the fact that if reassortment turns H5N1 into a pandemic strain, the resulting virus could be less virulent than the current version. Since late 2003 there have been 383 confirmed human cases of H5N1 infection and 241, or 63 per cent, of those people have died. The virus that most closely matched H5N1 for virulence was one with three avian genes, the hemagglutinin and neuraminidase, plus the PB1 gene combined with five genes from the human virus. Both the viruses from the 1957 and 1968 pandemics carried an avian PB1 gene. The authors suggest that picking up an avian PB1 gene may be a critical step in a potential pandemic virus arising through reassortment. But just because the viruses mated successfully in a laboratory doesn't mean those viruses could go on to trigger a pandemic. In order to have that potential, a virus would have to be able to transmit from person to person - a skill that has so far eluded H5N1. "The bottom line is it comes back down to transmission really being the key," Webby says. "But to say that we understand what are the factors involved in transmission is certainly an overstatement." Earlier work at the CDC on some H5N1-H3N2 reassortant viruses showed they failed to transmit from infected to uninfected ferrets, an animal often used in flu research. Donis says his team hopes to test its reassortant viruses in ferrets as well, but is still going through the approvals process. http://cnews.canoe.ca/CNEWS/World/2...pf-5740766.html |