The lull in bird flu is over. At least the lull in the news about bird flu. The virus didn't go away. Editors got tired of it and national agricultural officials were quiet about it. Now Thailand is again engulfed with poultry infections and experiencing human cases and Indonesia continues to percolate away with both bird and human cases. In both countries the endemic poultry problem is the underlying cause.
"When you have trouble controlling infection among the chicken flocks, you are naturally going to see continuing infections among humans," Dr. Anthony Fauci, the US National Institutes of Health's infectious disease chief told The Associated Press by phone in a recent interview.He said the more it spreads, the greater chance it has of eventually evolving into a strain that could cause a human pandemic.
"It's obviously a toll in human suffering, but it also continues to give this virus the capability of circulating," he said. "And the more it circulates, the more you have an opportunity." (AP via Shanghai Daily)
Fauci is worried because Indonesia has never had the aggressive program of culling around infected flocks that Thailand has pursued. But Thailand still has a problem. Vietnam has opted for vaccination, but some worry this obscures warning signs of infection and makes recognition of human cases more difficult. There doesn't seem to be a good way to stop this virus. In the last analysis, it will probably depend on its biology. If this virus is capable of evolving into a pandemic strain there won't be much we can do to stop it. If it isn't, nothing we will do will be responsible for preventing an outbreak.
This isn't a reason not to do whatever seems reasonable by way of controlling poultry infection and contact with humans. It is a reason to do everything we can to prepare our own public health and social service national defenses to cope with it if it happens.
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Do you love your cat? Cat flu may have arrived in Asia.
There are now indications H5N1 may have mutated into strains that exclusively use mammals, such as cats, as their host.
There is evidence cats may now be a mammalian host for bird flu. One virologist is now investigating this possibility in the field in Indonesia.
If this theory is correct, there could be multiple vectors from both birds and mammals for H5N1 to use as hosts to infect humans.
If it is discovered cats are now a dominant vector used by certain strains of H5N1 to infect humans, the name of H5N1 infections may need to be changed to cat flu instead of bird flu.
This means cats in the areas in Asia where there are large clusters of H5N1 infection may need to be destroyed.
And if a pandemic hits the US, caused by cat flu, cats in the US in areas where there are H5N1 clusters, would also have to be destroyed.
And since H5N1 may expand to infect other mammals, such as dogs and pigs; the same would also apply to these animals.
To delay may cause increased death in humans; and an exclusive concentration on the destruction of domestic fowl may result in a pandemic, as H5N1 takes up permanent residence in mammals.
At that point, leaders of Asian governments may decide there is no way to stop H5N1, and stop culling chickens.
Plus in the US, the very idea of killing even one cat or dog is repugnant. Therefore, if the situation described above becomes a reality; perhaps it would be best to just leave the animals alone; and let the humans die in mass.
Domestic cats are certainly a possibility, though I'm not sure they represent the hidden H5N1 repository we've discussed in indo and other places. Anyone know how many cats people keep in Indo?
Although cats may present a problem in the future due to their close association with humans, I believe the tertiary host is not the usual suspects pigs, dogs, cats but may be a small shoreline mammal, rats or bats.
H5N1 must be evolving in a mammal unknown to us at this time...the same occured with SARS...its the tool animal diseases use as a bridge to other species.
Sorry, I forgot to mention that those of you who may suggest an eradication of cats or dogs to prevent H5N1 that there are many good reasons why man chose to domesticate dogs and cats...rats are just one of them.
If we removed the cat population from the world...you might be surprised how much trouble we would be in with other diseases and food shortages and how fast this might occur.
Tom DVM,
A study by the Graduate School of Public Health at the University of Columbia in Hong Kong, at the apartment where there were many residents infected with SARS, determined roof rats were spreading SARS to the residents, and were a vector for SARS. Of course the dominant belief was that leaks in the plumbing in the apartment building spread the disease.
But there may have been multiple vectors of SARS in the apartment building in Hong Kong, just as there may already exist multiple vectors, from both mammals and birds, for the spread of H5N1 now,in Asia.
We know bats spread rabies, and so are a vector for rabies. And I believe the major vector for bird flu may be the rat. I believe that there is a high probability of rats being a major vector for bird flu, and rats should be tested. If rats are the major vector, it would be completly impossible to control bird flu outbreaks. In that case they should be called rat flu outbreaks. Remember fleas on rats spread the bubonic plague. How would you control a rat population in any major city? Would you evacuate the city and drop an atomic bomb on the city to stop an outbreak of rat flu? Do you note how absurd it becomes to think in terms of eradication of H5N1 in rat populations?
In a study by a university in Indonesia, field research in Java indicated, in an area where there was an outbreak of H5N1 in poultry, that the flies were also infected.
In a field study in a village in Thailand, where there were both human and poultry infection with H5N1, it was discovered that both cats and dogs were also H5N1 positive.
If both flies and rats are vectors, it would be impossible to control H5N1, if there was transmission via these vectors, to humans.
William.
I believe I read that 'Bats' instead of 'Civet Cats' were the original source (template) of the required mutation of the historically very stable coronavirus to produce SARS.
William wrote:
By definition, if a pandemic hit the U.S., it would be spreading human-to-human. If it were being spread cat-to-human, it would still be an zoonotic disease. If it were spreading readily human-to-human, and also cat-to-human, cats would be the least of our worries. After all, unlike their human owners, domestic cats don't travel long distances by themselves.
caia wrote: "domestic cats don't travel long distances by themselves"
While that's usually true, here's the story of a cat that went from Chicago to the UK via NY.
Niman said today that at the Los Alamos flu database,in regard to human and bird sequences from Jakarta, that had recently been sent to Australia for analysis, were released.
And the result is? The human and avian sequences do not match.
This failure to match sequences from Jakarta means the H5N1 infections in the Jakarta area are not directly related to poultry. In plain English: chickens are not the vector for the human bird flu infections in Jakarta.
So keep on killing those sick chickens in Jakarta; but do not expect it to do anything to reduce the threat of human bird flu infections there. Chickens may not be the vector for human infections in Jakarta.
Another,
If cats really are a vector for bird flu, or cat flu, and it is publicized, all you have to do is walk into an airport with a cat, and people will start to run for safety.
Then the cat can roam around the airport looking for food.
another: Hee! And wasn't there one who ended up in France by accident? I forgot about those. At any rate, such rare instances of cat travel would only be worrisome if they involved cats from flu-affected countries in a pre-pandemic period. My point was that if we were in a full human-to-human pandemic, the danger of the infection spreading from the hordes of human travellers moving by plane, train, bus, car, boat or foot would dwarf the danger from the cats they brought with them.
Which is not to say I wouldn't ask the neighbors to keep their cats inside and scare an feline intruders off with an airhorn. :)
Three things that I have seen in the last few days that scare the living shit out of me about H5N1 or whatever we end up with. First-SE Asian Governments are spending MONEY! Their money and not ours. They are singing the woes that they havent received 900 million in Indo for bird flu eradication. That by the way was supposed to be 1/3rd of the entire money for the eradication. Why? Well boys because there was no indication from their government that it was ever going to be used for eradication. Their own infrastructure plan was for destruction of birds and that done by compensation. WE all knew that they would hide birds, cull a few and say heres how many and then go right back to growing endemically infected flocks. They waited, we (the world) watched and it got a foothold. We harped on them, they said we have it under control. They of course lied, we waited for action and got none and now they do the #2. And the # 2 is that they took the big dumper when they found out that the money wasnt coming unless they played ball.
Second-Release of isolates and sequences across the planet for what they held from samples taken.
Niman has been furiously posting the info on the web and even a layman like me looking at GenBank can see the subtle changes in this monster. So now they and others are starting to release data and come clean. This includes the lying sack of shit Chinese who conveniently forgot to mention this little guy SHI in 2003. This is also about the time of the "ebola flu" on the outskirts of H. Kong in the old country. They forgot to mention that too. I STILL want to know about the 6500 that mysteriously turned up missing from flooding at the 3500 foot ASL in villages that were NOT near rivers. I got a briefing then that they thought that they had been trucked up country to the Mongolian border and left to die. You might remember this as being the second big story that came out of Boxun.com. SARS was the first they broke to the west and they are all residents of the Chinese Penal System at this time. Two got life for putting that one out.
Finally the Third. Number three is that Thailand has begun construction on quarantine faciilities. This they said was to "increase their medical capabilities." No kidding. Note that these were not isolation facilities, they are quarantine facilities. I got another briefing today and this is out there on Drudge and others that certain individuals in the medical world such as Fauci dont think they can stop this unless its done at the source. I would submit to you that its already over with. The war is on and he who is left standing is going to be able to say I beat Avian Flu. Our own Government-Gerberding saying that they couldnt make a pandemic flu in the lab. Well Hell folks, the fallacies of that are borne out not on the submitted papers but the NEWSPAPERS. We have H2H confirmed (just as we did in the lead up to 1918), we are getting peppered around the world with identified bird cases (just as 1918) and then in the fall of 1918 it roared in and kicked our collective asses.
So theres my read on this. Feel free to beat me up if you think I am wrong. I feel that we are being misled by EVERY government and have been since 1996. This includes Bill and HIll. But what else could they say besides everything is okay? To say anything else would have destroyed the world economy, everyone would have gone into a bunker mentality, and then as the resources dwindled some big damned war would have broken out. ......Hey, has anyone got Monica Lewinsky's number? I KNOW she would make me feel better about this.
Tom DVM/Revere, look at the latest post on CELL magazine about transmissible dog cancer. Far out!
M.Randolph Kruger,
I too have been reading Niman's posts about the subtle changes in the monster, and I too am fearful.
Perhaps the leaders in Indonesia knew that when they released the data, it would be like dunking us in a tub of icewater.
I think Randy Kruger is right. If only I could convince my kids in California of how imminent is this threat, then they might do something to prepare in time to save their and their children's lives. But with government authorities and the media remaining complicit in downplaying this threat, I am just good old chicken little. This is where the whole thing gets personal.
I do have a question about transmission: From what I understand, the H5N1 virus infects cells in the lower parts of the respiratory tract. This is its point of entry into the host. Some of Dr. Niman and other's discussions mention a concern that a certain mutation may allow it to infect cells in the upper respiratory tract with different binding sites, and that change could be the key to H2H transmission and pandemic. So: two questions actually...One, in these recently released DNA sequences, is there evidence that particular mutation has occured in any significant numbers? And Two: if the infection sites are in the respiratory tract, how are people, cats etc getting this disease from exposure to infected poultry blood and/or feces? Do the virus particles vaporize up out of those body products, become airborne and get inhaled? Or do we need to rethink this method of transmission?
I am interested that "culling" is being constantly advocated in this forum as a method of control of the spread of bird flu.
There are many good reasons why culling is *not* an appropriate response in areas where village chickens/backyard poultry are an essential part of the agricultural and food ecosystem.
Asking people to sacrifice their livelihood and food source, for a disease which has, thus far, killed far fewer people than TB, malaria or polio (and which many who live in endemic areas in Indonesia do not view as a problem) is not likely to be effecacious.
Additionally, mass slaughter of backyard poultry may have undetermined flow-on effects (just look at the rise in tick borne diseases in Turkey due to the slaughter policy, given that the chickens used to control ticks) - vaccination would be a better option to help prevent these and decrease disease incidence.
I am not denying that HPAI H5N1 may evolve into a potentially lethal pandemic. However, grandstanding from afar about culling chickens in some of the affected countries is neither helpful nor effecacious in changing behaviour.
"Reducing risk behaviour" is also difficult when the population density cf poultry density is compared. Perhaps it would be of use or interest to the various Reveres to consult with some of their colleagues in veterinary epidemiology and public health in this field.
Here's the blowfly papwer
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&do…
attack rate: We have taken a neutral position on culling. In several posts here and on the old site we have raised questions about it but we don't have a good evidence to say it doesn't work or doesn't slow things up. At the moment culling or vaccination seem to be the only possibilities and both have disadvantages. We will continue to be neutral until it is clear it is a useless method or that it does more harm than good.
Our major problem with Indon is not that they don't cull aggressively (we have suggested many reason why they might not) but that they have no plan, no infrastructure, no control, no effective surveillance, etc. It is a viral free fire zone.
Mary in Hawaii,
Please go to www.recombinomics.com and read the August 1,2006 post. Human H5N1 injected into experimental, inoculated ferrets produced high titer levels of H5N1 in the upper respiratory tracts of the ferrets.
This may mean H5N1 is no longer restricted from entering the upper respiratory tract of human hosts, which may have resulted from recent mutations of H5N1.
If this theory is correct, then some strains of H5N1 may have the ability to enter and multiply in the upper respiratory tracts of human hosts, increasing the chances for a pandemic. All the patient with infection of the upper respiratory tract with H5N1 would have to do is cough, and the vaporized virus particles could stay suspended in rooms for perhaps hours. Of if the infected person got on a plane, he or she might infect many other passengers.
Today's post by Niman indicates there is some other source for human H5N1 infections in Indonesia than poultry. And we do not know what that source is. But mammals, such as cats,
should be immediately tested, since blood from a cat is the only match we have.
attack rate,
Culling chickens may not produce the desired results in the control of H5N1 in humans, since the virus in humans has now mutated away from any avian source.
While Indonesians are killing thousands of chickens, the virus, which is much more intelligent than human life forms,
may have moved on to a new host, such as a cat.
So when someone who is culling chickens all day, comes home; and his cat puts cat saliva on his or her hand and face, the monster H5N1 might enter his blood stream and kill him or her.
Human beings are intelligent, but H5N1 is even more intelligent.
william: we have posted on this numerous times as well. The upper tract of humans and ferrets probably have α2,3 receptors so no mutation is necessary. Also, while it is sometimes useful shorthand to attribute intelligence to the virus, it has none. It has no schemes or tactics. It only has arithmetic, which i more than enough.
There is a great deal to learn about transmission and animal reservoirs, to be sure. This all takes more time than most of us feel comfortable wih and there are many avenues that urgently need exploration, cats being one of them. There are currently not enough hands to do all of this. So we better hope we get lucky in the avenues we do go down. Your concern with cats is just one.
We now need to advocate for a repository of specific clinical information in human cases. What we need to know is related to the survival rate, not the fatality rate. A good comparison is the East coast anthrax cases of 2001. From the clinical data, it was determined that if you presented to the ER with symptoms (ILI) and they correctly diagnosed you and started the appropriate antimicrobials, you lived. Two aspirin and call me in the morning, you died. HK-SAR Vietnam and Thailand shared early, (from Wong and Malik) but there has been zip since then and Indonesia has shared zippo.
Did the survivors live because they had mild cases?. The right gene pool? proper and/or early intervention? The last line of defense will be how to keep someone alive while the infection, (a self limiting one) runs its' course.
Where do we start?
Might it not be a better option in the event of an HPAI H5N1 outbreak in poultry to try and contain it to the infected site, allow it to run its course (normally a couple of days) and see if there are any survivors. If there are take them away and quarantine them until they are shown not to be shedding virus and use them as breading stock.
If, as seems to be the case, H5N1 is endemic in SE Asia and that status is likely to spread to other areas over time, it seems fairly pointless to cull flocks at the sign of first infection only to disinfect and reintroduce another batch of immunologically naive domestic poultry. A better options would seem be to fight nature at her own game and selectively breed from poultry that show some level of resistance and through iterations develop a chicken better adapted to this new H5N1 world.
Mitchell's recommendation regarding the need for an open database of information on clinical presentations for H5N1 in humans is particularly important given the continuing uncertainties surrounding the true frequency of asymtomatic or atypical H5N1 presentations in humans.
Research published to date indicates that the differential diagnosis of H5N1 should include a number of other serious and potentially fatal diseases that prevalent in southern and eastern Asia including (among others) Japanese encephalitis, dengue, cholera, typhoid, and bacterial meningitis.
For example, human mortality from H5N1 could be a full order of magnitude higher than current WHO statistics indicate (i.e., several thousand instead several hundred fatalities) if only one percent or less of the assumed -- but unconfirmed -- fatal "Japanese encephalitis" cases in SE Asia during the past three years actually involved unrecognised fatal atypical H5N1 presentations.
William (and Revere) You tell me to read Niman's post about ferrets and upper respiratory tract. Hello...I know, this is what I was referring to. My question was not DOES H5N1 infect via human's upper respiratory tract, it was HOW does the viral particles in the blood and feces of chicken get into the human upper respiratory tract. Your answer, apparently is
"So when someone who is culling chickens all day, comes home; and his cat puts cat saliva on his or her hand and face, the monster H5N1 might enter his blood stream and kill him or her."
You say the H5N1 might enter his blood stream and kill him. I pointed out that it enters the cells in the respiratory tract to infect the human. Are you suggesting it travels to the respiratory tract via the blood stream (after entering victim's said blood stream via some cut in hands or mouth or digestive tract?) I don't think so. Do you understand my question? It is not a stupid question, nor an unimportant one, nor an uniformed one. How does a "blood borne" virus particle become an air borne virus particle which infects a human via their lungs? (Virus particles in blood and feces, the medium is liquid, not aerosol.) So, will someone actually take a look at this discrepancy and think about it?
Thanks Zo Kun. My biggest concern now is, "which turds floating is the punch bowl of life are from the fan? We will be inundated with flake/fake flu. Accurate testing will be the key. If you don't have the H5 chill, just chill. Our best response will be to gain confidence and then success.
mary: We don't know the sources and modes of infection for the most part. The assumption has been that virions are inhaled from contaminated dust (including fecally contaminated dust0 but as we have pointed out there are other routes, including intestinal and through the conjunctivae (eyes). The most direct route is inhalation, but we know very little about other routes, e.g., through the lymph system from the oropharynx or nose or intestines. There is not much evidence one way or another. I'm not sure if this is answering your question, however. Remember that a virion not only has to get to the tissues, but it has to find cells with the right "docking" molecules and other factors that allow infection. That can make it look like a virus is "finding" a tissue when it is just passing by tissues without the proper markings rather than actively finding cells to infect.
People are often surprised at how little we really know about flu infection and its mechanisms, so it may be that what you are asking isn't known, although I'm not sure I understand your question.
William, it's possible that flies could be a vector. The role of M. sorbens in C. trachomatis, is also a good example. We need more follow-up. Trouble is we don't have the facilities for this overwhelming amount of testing.
Revere and Mary: Given the difficulty we have in the past of finding virions in the bloodstream, I'd say the lymph system is probably the transportation network of choice for H5N1 when it's on the move, except for when it's in the brain. The cranial nerves (and possible the optic nerves) are known ingresses of entry.
Hi Revere: thanks for answering, and let me try to be clearer. I do understand that there are specific sites on specific host cells to which a given virus will bind. In the case of H5N1 from what I have read the primary binding site is on some cells in the lower respiratory tract. (Then there is some recent evidence that some of the H5N1 mutations have demonstrated ability to bind at different host cell sites found in the upper respiratory tract. It was also indicated that this ability may be a precursor to the virus become much more easily passed from human to human via sputum from sneezing or coughing.) Lower respiratory tract infections don't usually send the virus out into the air. So my question is twofold: One, in the "normal" H5N1 flu that affects the lower respiratory tract, do the virus particles enter the bloodstream first, say from exposure to infected chicken blood during butchering, and from there are carried to the lungs to cause this infection? Or are lung infections of any sort usually caused by the inhalation of the virus particles? I believe you answered my second question, which was related to feces> I was picturing wet fecal matter (especially considering the climate of indonesia and thailand) rather than dried feces, which could then become airborne. However when they test poultry feces for active virus particles, are they testing dried out dust-like feces or still wet feces? If is the latter, it would seem that airborne feces wouldn't be a route of infection. If it's not, then there is still the question of what the mode of transmission is between birds and humans.
mary: The question of where the receptors are in humans (or most other animals for that matter) is still unknown. The two papers in Science and Nature that implicated type II pneumocytes deep in the lung I believe were misinterpreted by many. They are sites of the virus in those studies but not the receptors, which weren't studied. Two other papers have shown "avian" receptors on ciliated cells which are most definitely upper respiratory tract cells. It may be that &alph;2,3 sialic acids in mucus shield those cells from infection most of the time but we don't know. We also don't know where, if at all, other α2,3 receptors might be, e.g., in the respiratory tract. There is evidence for them in the conjunctivae, so the eye, and through the nasolacrimal duct the oropharyunx is another route. There is still much to learn about this and studying it isn't easy.
I ran a google on avian flu and found that typical avian flu's that poultry farms have had to deal with are pretty easily decontaminated. Exposure to sunlight, drying, warm temperatures above 90 degrees F, and ultraviolet light will kill them. They will survive in manure up to 105 days. They need moisture. Regular soap and water, mild bleach solutions will kill it. So will alcohol. Washing clothing in detergent will kill it. In the event of infection, droplet and fomite control (face mask, hand washing, staying 3 feet away) are needed for anyone wishing to stay clear of it.
Is the H5N1 avian flu similar in that it is easy to decontaminate, or is it more persistent? It seems to me that cleanliness, natural and uv lighting might be enough to stop the spread.
I've found nothing specific to H5N1 decontamination yet.