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after outbreak in Nigeria, Feb 2006, a little more:
– just saying “wild birds” and “flight paths” is woefully inadequate; not sure any piece of land not permanently covered by snow/ice does not lie under skies travelled by at least small numbers of birds. Though “flyways” tend to mean routes travelled by larger numbers of migrants, more akin to rivers of migratory birds.
Nigeria, for instance, indeed lies on flight paths.
Surely flyways here, too, especially along coast (I’m less familiar with migration there than in e Asia).
But these for birds from Europe – not from H5N1-hit areas of Russia.Migrants will fly minimum they need to, in order to maximise survival chances. Can involve long distances, but broadly those from northern hiemisphere will head south for winter if suitable destinations for enough birds.
Poyang Lake in e central China and Qinghai Lake in nw China (1700km apart) just reported to have had same H5N1 strain in wild birds (well, 2 strains in 6 ducks at Poyang; big outbreak Qinghai).
This said to show wild birds were the link.
Now, both have “wild birds”, both lie on “migration routes” [no part of China does not, tho are places with more distinct flyways). But, take a more detailed look, and does not appear they are linked by migrants.
Poyang a winter haunt for birds from Mongolia eastwards and northeastwards – I’ve studied some as they migrated along the coast at Beidaihe, east of Beijing [a huge distance from Qinghai]
– see eastern flyway map for Siberian crane at http://www.sibeflyway.org/Map-Eastern-web.html – gives some idea of routes Poyang birds follow, tho at least some mainly migrate just inland rather than along coastal route
Qinghai Lake a breeding ground for wetland birds wintering in India, sw China.Post edited by: martin, at: 2006/02/09 00:58
Post edited by: martin, at: 2006/02/09 01:57
Post edited by: martin, at: 2006/03/19 00:54
A dead Japanese White-eye found on steps of a school in Mong Kok, Kowloon, tested positive for H5.
Another species that seems odd for infection with H5.
Very common cagebird; Mong Kok is close to major bird markets. Also common in wild – inc in trees in urban areas.The egret has tested positive for H5N1.
A dead chicken found abandoned (with 2 live chickens) in Tuen Mun, nw Hong Kong just tested positive for H5.
A little egret found dead nearby has indicated positive for H5.Yes, paper showing live ducks capable of flying with H5N1; haven’t shown they actually transmit it, tho of course plausible.
Quote:The existence of distinct clusters also means the main carriers cannot be wide-ranging birds – instead, most transmission is via local poultry movements. Co-author Malik Peiris, of the University of Hong Kong, told New Scientist: “If there had been repeated waves of virus introduced into, for example, Yunnan, one would expect multiple sub-lineages of the virus. But in each place there is only one.”surely important
Quote:Long distance transmissionBut wild birds are involved. The team found H5N1 in six apparently-healthy migratory ducks at Poyang Lake in Jiangxi province, which borders Guangdong and Hunan, in January and March 2005, before the northward migration. The isolates had all the genes, and certain specific mutations, later found in geese at Qinghai Lake, 1700 kilometres northwest. And this virus, notes Peiris, is very like H5N1 in Turkey.
but, these places not linked by major migration routes; Poyang winter birds don’t – for vast majority – move to Qinghai, instead to Mongolia, ne China and beyond.
Quote:The team also tested whether the Poyang viruses would make ducks too sick to fly by infecting young mallards. “Most got a bit sick then recovered,” says Webster, and all shed virus for up to a week. “The evidence is now overwhelming that migrating birds can move H5N1 over long distances,” says Peiris. “But they are not the scapegoats for maintaining H5N1 within poultry. There the cause and solution lies within the poultry industry.”Just had a read of paper; plenty of questions arise tho too tired after long day in field to do much now; may open separate thread.
George W Bush, u mean – that patsy now getting touchy feely about poor kids, and even a little worried about overusing oil? Brits like me may not so much blame, as feel just a little pity.
Post edited by: martin, at: 2006/02/07 12:16
Why following only very few migratory pathways? [ever checked, say, route of Trans-Siberian rail lines]
(And u care to show me someplace that isn’t on a migratory pathway)
Why not in Asian waterbirds this winter? There are migratory pathways here too, you know.
Have you seen, for instance, autumn migration routes from Qinghai Lake?But, u wanna keep believing in dead birds carrying H5N1, go ahead.
Post edited by: martin, at: 2006/02/06 02:06
Perhaps useful article, originally in Fortune:
How disease evolvesincludes:
Quote:natural selection doesn’t favor very vicious bugs when transmission from sick hosts is difficult, for the hosts literally become dead ends before the bugs can leap to others. In such cases, milder strains tend to become the dominant ones in circulation.Which in case of bird flu, is roughly summarised by Dead Ducks Don’t Fly
(Even though dead ducks n other birds said to be spreading H5N1)
From further email from Wendy Orent:
Natural selection works on a genetic and individual level, not a population level. When you are talking about viruses, think of a swarm of strains, some of which are going to be more effective under the particular conditions they find themselves in (a host, or group of hosts, under particular ecological conditions.)
These influenza strains (say) are all madly jockeying, so to speak, to outreproduce each other (of course, this intentionality is strictly metaphorical.) Now, let’s say we are talking about a population of wild ducks who are infested with low-path H5N1. If there is a wide range of strains within duck A, those strains best at exploiting that duck’s body will reproduce better and faster and more effectively than milder strains. So, in the competition to use up the duck, so to speak, MORE virulent strains will win out.
Now, here’s the thing. That duck is dead – wiped out, gone. But duck B, which happened to get a smaller or a milder set of strains, doesn’t die; he lives to pass whatever virus he is dealing with to ducks C and D. So those milder strains are going to win out – and spread through the duck population. It has nothing to do with equilibrium – only with the balance between within host and outside-host competition. You sometimes do find dead ducks in the wild, because natural selection is blind as a cavefish and can’t see what’s going to happen a duck or so down the road. If you get a mutant that increases virulence, that will put virulent strains at a temporary advantage. But that virulent strain won’t spread – that’s why Ewald speaks of the “sieve of natural selection” when he talks about flu in wild migrating birds.
…
Change the conditions, and you change the equation – that’s the point of “disease factory” conditions – you remove the penalties on viruses for being virulent.Post edited by: martin, at: 2006/02/06 00:13
Quote:Preliminary testing of a Common Magpie found in Sham Tseng has indicated a suspected case of H5 avian influenza, a spokesman for the Agriculture, Fisheries and Conservation Department (AFCD) said today (February 4), adding that further confirmatory tests are being conducted.The bird was collected by AFCD staff in Yuen Tun Village, Tsing Lung Tau following a public referral on February 2. Appearing sick at the time, it was transferred to the department’s Animal Management Centre/North and died the following day.
The spokesman said there is only one commercial chicken farm within five kilometres of where the bird was found. No abnormal mortality or symptoms of avian influenza was detected among the chicken flocks upon inspection.
http://www.info.gov.hk/gia/general/200602/04/P200602040170.htm
This is on west coast of the New Territories (near Tsuen Wan), so not real close to the other recent H5N1 reports in Hong Kong.
Magpies have tested positive for H5N1 before (eg ne China), perhaps contracting after scavenging carcasses of infected birds.
Not far from Wong Tai Sin (crested mynah), but also not a species I’d expect among birds released in ceremonies.6 Feb update: results positive for H5N1.
Post edited by: martin, at: 2006/02/06 15:15
Quote:Researchers and health agencies continue to sound the alarm about avian flu, and Dr. Gary Butcher, an expert on poultry medicine and disease at the University of Florida’s College of Veterinary Medicine thinks he knows why.“The agenda here is pretty obvious,” he said. “People want grant money. This is a bonanza.”
Butcher, who advises agricultural ministries and poultry companies around the world, is Florida’s lone poultry veterinarian. He has also emerged as a leading naysayer on the prospects for a avian flu pandemic.
Butcher insists the likelihood that the H5N1 avian flu virus in Asia will trigger a pandemic is practically nil. But the fear-mongering will continue, he said, as long as people see a potential for financial and career gain in it.
…
“This is a full-on war against agriculture,” Butcher said – and he is firing back.
…
“The threat is basically zero,” he said. “We’re spending all of our attention on this [virus], and another one may sneak up on us.”
…
The WHO’s Web site also warns that the H5N1 avian flu has killed half of the people it has infected. That’s true, Butcher said, but given the fact that the virus has only infected roughly 130 people, that 50 percent statistic paints a misleading picture. [note: this is of people known to have been infected; cf ideas many infected without much illness]“The guy who wrote this really wants to make this sound like a big thing,” Butcher said, reading through the WHO’s “frequently asked questions” about avian flu.
“Dr. Butcher is certainly entitled to his opinion,” WHO spokeswoman Maria Cheng said in an e-mailed response. “We clearly do not share it.”
…
The veterinarian reserved some of his harshest criticism for the USDA, which he believes is overstating the threat to justify its intensifying bird surveillance programs and gain funding and influence.“They’re trying to keep [avian flu] in the spotlight,” he said.
“Everyone’s keeping it in the spotlight,” said Madelaine Fletcher, spokeswoman for the Animal and Plant Health Inspection Service division of the USDA.
…
Butcher’s perspective is not only that of an academic expert, but that of an industry consultant. When he is not teaching and researching in Gainesville, Butcher often travels to Panama, Russia, Ecuador, Vietnam, Thailand and other countries, advising governments and poultry companies whose survival and profits are threatened by public fears of bird flu.In his travels, he said, he sees the evidence of serious economic harm caused by misplaced fear. “Poultry consumption is down 50 percent in Europe,” he said. “It’s a disaster.”
…
But Butcher remains troubled. “I don’t think people understand the effect its had on economies, industries and even the mental health of people around the world,” he said. “It’s prudent to be prepared, but it’s not prudent to inspire this overreaction.”Ruffled feathers
UF professor says bird flu is not a threat in the U.S.I sent email with idea re the mynah being among batch of birds released at temple, inc Chris Patten releasing birds in 1997, to HK Agriculture, Fisheries and Conservation Department; obviously too brief in email, as just received:
Quote:Thanks for your email dated 1.2.2006 Since the release was done in 1997, we cannot ensure whether the mynah therein is one of the birds in the batch released. Thank you for bringing the matter to our attention.to which I’ve replied: I hadn’t meant the mynah was released in 1997! That was just to show that bird releases can take place at the temple. I meant, instead, the mynah was maybe released there during this Chinese New Year. (At Wong Tai Sin temple or nearby). If so, the mynah was not a wild bird, but was captive. The magpie robins maybe also captive (for fighting?) – have they been examined for signs of this? Captivity/trade a far more likely means of these birds becoming infected with H5N1 than any contact with wild ducks (where to find these in HK outside Deep Bay? – not easy) For instance, in Shenzhen I’ve been to market where they had both poultry/farm animals, and wild animals inc birds. This species is commonly sold in markets in s China:
Wild Animal Trade Monitoring Selected Markets Guangzhou Shenzhen (pdf file)
back to “a correspondent”:
Quote:We need a genetic explanation. Like Niman and ProMED, some people
regard the genetic similarity as evidence for migration theory.
My genetic interpretation is completely the reverse. The lack of
genetic variation is a result of “no natural selection” (evolutionary
stasis), i.e. the observed similarity is a genetic proof against wild
birds as vectors. Such a degree of “no natural selection” (as well as
the lack of reassortment) certainly requires artificial environment,
i.e. poultry. Wouldn’t that be a breakthrough? What we need is an
expert’s verification.Quote:I have been just informed of a domestic TV program tonight,
highlighting “novel transmission ways” of flu. According to the
program, two new ways will be presented: mildly symptomatic people
(less immune reaction) and Tamiflu-treated people (I have read
numerous reports Tamiflu-treated mildly symptomatic people enter
crowds, spreading the virus). The can easily become “transmission
hubs”, making the spread easier and more preserving the virulence.Wendy again:
Quote:Nah, this doesn’t work at all. Mildly symptomatic people will produce mild strains…the disease will move towards mildness. That’s the whole point of Ewald’s argument. I don’t know how much Tamiful treatment changes this picture – very little, I would think. The “less immune reaction” is a complete red herring. Less immune reaction is caused by a less virulent strain. In all cases, having people well enough to walk about will only decrease virulence, not maintain it or add to it. I suspect Tamiful-treated people will just recover more quickly and be less effective transmitters – remember, the virus has got to make you sick – coughing and sneezing- to get itself out and into someone else.and correspondent:
Quote:Not all individuals react to the same (or similar) strain in the
same way. While the virus is less virulent to some people, there
still remains a possibility of a higher virulence to the rest.
(We already know the present H5N1 has shown different reactions to
different ages, but the reason is unknown. An asymptomatic crow
infection, with systemic viral replication, is already experimentally
known, which excreted sufficient viral load to infect other birds.
This shows less symptomatic populations in the same species can emerge).By the way, I am not trying to argue “how dangerous the virus is”,
but Ewald’s argument expects the “expected mean”, not clearly directed
to the “potential upper limit”. Predictions assuming some kind of
an equilibrium or “mean field approximation” would fail in certain
conditions, especially there is a background variation (different
responses in populations). This is the very point recently targeted
by the complex network theory or modern numerical ecology.Right, time to break things up a little; still re the above correspondence, but here, some comments from Wendy Orent:
Quote:Dear Martin,These are all good questions. I wish we could make it clear to
everyone that it isn’t crowding, per se, that is the crucial
condition. It’s the ability to transmit the germ repeatedly from
immobilized hosts to the well. People can be packed like sardines on
a train, subway, or plane, even for many hours, and not do anything
to advance the virulence of a respiratory pathogen like influenza. If
you’re that deathly ill, you are not getting on the plane, unless
you’re carried on. Even if that happened, and a number of people
caught a disease like that, whatever they caught would quickly lose
virulence – unless you kept people packed in together for weeks, or
months, or whatever it ttakes – no one knows. I.e., you’d need a
disease factory to develop virulence and transmissibility, and to
keep it going. I can’t think of any disease factory conditions on the
planet right not – World War One doesn’t happen frequently.
The whole plane thing is a red herring. We are not talking about
spreading a disease around the world; we’re talking about the
evolution of virulence. That is not going to happen on a plane in
normal circumstances – I mean, absent a plane getting hijacked with
someone deathly ill on board, and keeping people trapped on boared
with that person for weeks. Even then, it’s iffy…we don’t know how
long the evolution of virulence, or of transmissibility, takes.As for contagiousness before symptoms: people love to trot that out.
But how does it work? You really can’t shed too much virus if there
isn’t a huge buildup in your upper respiratory tract. You might be a
little contagious, but only a little. It’s the symptoms that make you
contagious – the sneezing, the coughing – the virus’s little way of
making its host shed it into the world, where it hopes, so to speak,
someone else will pick it up. Anyway, the severest disease appears to
be that where the virus or bacterium replicates most quickly and
exploits the host’s tissues most thoroughly. It doesn’t give itself
the long window of being shed. Plague – the right sort of plague
(from marmots), not all plague – was pretty good at this – it’s
what’s been called a “stealth infection” – it suppresses the immune
response, inflammation, fever, everything – so the body doesn’t know
it’s under siege. That’s what people appear to keel over and die so
suddenly from pneumonic plague. They’re half dead while they’re still
walking around. But they aren’t shedding that much virulent bacteria
for all that time – their lungs have to get pretty destroyed before
they start coughing the blood-tinged sputum that’s infectious. That’s
plague – that’s not flu…you’d cough earlier in flu, but it’s just
not that deadly a disease – even 1918 killed 2-5% of its victims
(pneumonic plague kills 99.9% – it’s too lethal to people to exist
for long as a human-adapted disease.) So rule of thumb is –
contagiousness before symptoms is almost an oxymoron – you’d have to
be sneezing or coughing, at the least, to shed a lot of bugs. I
imagine that the deadlier the disease, the shorter the window of
contagiousness while you’re still up and walking around. Point being:
people with deadly flu aren’t going to be shedding it for very long
before they’re wiped off their feet.You’re completely right about the wild birds, though I think the
Gaussian thing might be a red herring (though it’s also possible I
don’t clearly understand what you meant. It isn’t a question of the
mean in natural selection.) The thing is, wild birds can catch
high-path flu, die of it, even spread it a little, LOCALLY – but they
CAN’T maintain it. High-path flu can’t survive the sieve of natural
selection.Quote:> Rather as I’m also sceptical re vaccinations, perhaps helping
sustain h5n1 (when vaccinations and surveillance less than near
perfect).
A GOOD vaccine would be the way to go, if we had one – but for what
disease? Human-adapted H5N1 doesn’t exist yet, and no one knows what
it would look like if it did.(I’d meant I was sceptical re vaccinations for poultry)
Quote:Equilibrium theory is for sure a red herring. Selection works on the
level of the individual organism or the individual strain or genetic
line – not on the population or species. A non-pathogenic strain in
people would mean that the virus wouldn’t get shed – it’s got to make
you sick to make you shed X;{ , or we’d all be infected with scads of
things we just pass around all the time, without ever getting sick
(some things, like staph epidermidis, do probably pass around this
way.) But wild birds just pass the bug in their feces – harmless
intestinal bugs, like most enteroviruses in people.Had lengthy correspondence re natural selection and H5N1, with “a correspondent”; also led to comments from Wendy Orent.
> Indicates quoted text within the chunks of quoted text – gets a bit complex like this I’m afraid.Lest of interest, here goes:
Again, the paper by Ewald, with predictions re evolution of pathogens including flu:
Quote:Yes, this is well-known. This is a famous piece in learning
ecology in terms of natural selection. This is a reason why experts
more fear a long-range transport (either by humans or birds) than
gradual geographical invasion.But we can’t predict exactly, particularly when various species
are involved. We don’t even know why LPAIs are so “evolutionary
static” in wild ducks, while they can be so pathogenic to humans
when they happen to enter the human world. The only truth is
“natural selection works”, but we may not know or deal with all
factors of natural selection.But again: Ewald makes predictions re flus becoming pathogenic entering human world.
Takes special conditions – very sick people able to readily transmit – to evolve a dangerous flu.
Most extreme in 1918: First World War.Mao maybe helped cause 1957 and 1968 flus.
No such special conditions today; so Ewald argues that we won’t get a highly pathogenic human flu today.
His theory predicts avian flus will be mild in wild birds. Need to have birds flying to carry the flus, so evolution to mild strains. So, to me, we do know why LPAIs are “evolutionary static” in wild birds.
High path strains into wild birds, and quickly to low path. Or extinction.Quoting Ewald directly:
“With regard to the future I am predicting that such a highly lethal pandemic (i.e., 1 death per 50 infections) will not occur, not from H5N1 and not from any other influenza virus that will arise unless regional conditions allow transmission from immobile hosts, as they did on the Western Front in 1918. This is not “speculation” as is claimed by our hooded critic with the self-aggrandizing name. It is a prediction based on careful consideration of theory and evidence. The future will demonstrate whether it is accurate.”
http://blog.sciam.com/index.php?title=bird_reaper_pt_iii_paul_ewald_replies&more=1&c=1&tb=1&pb=1Makes sense to me.
Can make analagous predictions for birds (Ewald does so for poultry):
– crowd together, indefinitely, so sick birds can readily transmit: and evolve dangerous flus
– wild situations, need birds to fly to transmit, and equilibrium when flus are mildThat is, predictions fit what we observe. Which to me is science; and not speculation.
Only mystery to me is why this is so widely ignored.
Quote:> No such special conditions today; so Ewald argues that we won’t get a
highly pathogenic human flu today.As I have (indirectly) heard from flu experts, some argue the virus
will not enter the human world in the HP form, but others’ claim
is different — we (even virologists) don’t know how HPAI will behave.“Most extreme in 1918: First World War”
> No such special conditions today
Wouldn’t airplanes, locomotion, population density be special?
We have never met a pandemic strain in such extremely globalized
world — we don’t really have an experience.> His theory predicts avian flus will be mild in wild birds. Need to have
birds flying to carry the flus, so evolution to mild strains. So, to
me, we do know why LPAIs are “evolutionary static” in wild birds.Yes, this explains “why”. We don’t exactly know “how”. This
means we don’t know exactly how selection pressure works. (Also
we don’t know how Zq strain retained high path to natural hosts).
As we haven’t seen LPAIs arising from Zq strain, we don’t know the
time-scale this process would require (may not be “very quickly”).> High path strains into wild birds, and quickly to low path. Or
extinction.Most look like to be going extinction (i.e. R0 But planes, crowded conditions etc not enough to him; not so special.
Need to have very sick people – immobile with disease – able to readily
transmit the virus.
Crowding doesn’t matter here, if very sick people stay
home/hospitalised.But flu is already contagious during the incubation period.
Less traffic than in WW I? Less packed people? (imagine Tokyo
trains) Though I can’t figure out the effect, all present factors
seem to increase the risk of a more virulent pandemic.> I’d figure that with wild birds, there’s always potential for virulent
flus to evolve.
Spectrum of virulence it seems to me (this from chemistry background,
not viruses): get some higher path, others lower path. Get an
equilibrium, depending on prevailing conditions.
As need flying birds to transmit flu in the wild, the equilibrium is
greatly towards non virulent forms. High path forms stay rare. (This
again from chemistry; some memories from when I did this re systems
reaching equilibrium.)Thanks! This is much easier to understand. If “random” distribution
of mutated form is close to Gaussian, natural selection would work
in this way (for a specific species). If it is very far from Gaussian,
we can’t be sure (because there is no effective average — this might
explain some of social phenomena like Zipf’s law). What if some
populations (due to genetic diversity) are more resistant (not all
infected individuals die, but can excrete substantial amount of the
virus) — we probably need a more complex view. Natural selection on
incubation period may also occur.> Could well be that doesn’t matter what bird species is: if cram into
captivity, infect with flu, and have substantial chance that birds with
high path forms can transmit flu, then will get evolution towards
higher pathogenic forms.If this is population density-dependent, how can we be sure our
population density is below a threshold where high path strains can
be sustained for a meaningful (effective transmission to a next
cluster) time? What is the major difference from poultry chickens?
(Well, some of recent pandemic plans from various companies seem to
assume “forced working” of employees with milder symptoms — they
will mix healthy populations during movement or in taxis — we may
eventually be poultry chickensOne more on “equilibrium theory”, why we have never seen a human
pandemic strain eventually forming a non-pathogenic form (as in LPAIs
in wild ducks?) What would be the difference between ducks and humans?
(Why “evolutionary stasis” is never reached)By the way, when considering selection pressure, won’t the extensive
use of Tamiflu in pandemic lead to a more virulent strain? Not
necessarily drug resistance, but won’t we be selecting a more neurotrophic
strain (since Tamiflu doesn’t effectively cross the blood-brain barrier),
I casted this question to a public health expert, but haven’t received
a reply. This might be another factor different from past pandemics.Well, now you ask questions I wish I had all answers for! – should really go directly to Paul Ewald, as I have some understanding but relatively superficial (I’ll forward to science writer Wendy Orent, who has written several articles based on his ideas, and with whom I’ve had some correspondence; she’s now in aiwatch).
The packed people, Tokyo trains or Hong Kong malls, not so important – if people who get sick, v quickly go to bed/hospital.
Seen re flu becoming infectious before symptoms; queried Wendy re this.
How infectious, I wonder, if not coughing/sneezing? How do you transmit virus without doing these things?Gaussian curve: not sure, but it’s my way of understanding things, as noted based on (physical) chemistry.
Main thing w poultry farms, to Ewald, is that can have (ready) transmission from even very sick chickens – so dangerous forms can transmit, even intensify.
Wendy notes that 1918 flu did become non-virulent, and still circulates.
I also don’t know re Tamiflu; hadn’t known this re brain.
Doesn’t seem wise, to me, to use it extensively; cf antibiotics and resistance.
Rather as I’m also sceptical re vaccinations, perhaps helping sustain h5n1 (when vaccinations and surveillance less than near perfect).Quote:> Seen re flu becoming infectious before symptoms; queried Wendy re this.
How infectious, I wonder, if not coughing/sneezing? How do you transmit
virus without doing these things?If high path mechanism (replicate without trypsin) indeed works,
we don’t necessarily require respiratory organs. Virus replicates
everywhere in the body.> Wendy notes that 1918 flu did become non-virulent, and still circulates.
The 1918 flu once disappeared (around 1950), reappeared later
(likely from a lab) and now circulating.Quote:What if some
populations (due to genetic diversity) are more resistant (not all
infected individuals die, but can excrete substantial amount of the
virus) — we probably need a more complex view.I’ve noticed that this possibility is a real concern. If such
individuals (or individuals of different species) are sporadic, we
don’t need to worry. But if chains of such individuals are
established? — This corresponds to the “percolation theory”.
(You may have read Simon Levin’s “Fragile Dominion” or Kauffman’s
“At Home in the Universe” in relation to percolation leading to
phase transition and its role in ecosystem).Quote:> Well, not sure if water-borne disease should be more specialised to
this transmission route, between humans. Like cholera.
And like cholera, can’t imagine it becoming widespread, but more in few
places w bad sanitation.
Worst SARS outbreak outside hospital (that we know of) was evidently
from sewage (apparently from toilet, somehow reached people’s showers,
and several people infected in an apartment block). Looked scary, but
proved isolated.Natural selection works as if a pathogen is seeking for a higher basic
reproduction number (not plainly necessarily less lethal). If a pathogen
has an ability to spread in a more efficient way, this would become
a primary route of transmission. If the virus replicates in intestines
or kidneys, sewage would be an efficient place for viral adaptation
(much resembling avian infections??).Quote:> As discussed, I don’t believe Osterholm is correct re predictions.> What may happen though, is that if get pandemic – and no matter if it’s
relatively mild – panic will lead to problems.
Already too many problems (such as worry, Tamiflu stocking etc), even
in US – where no H5N1, just fear of the disease.As we know, our existence is dependent on the present biodiversity
— a product of ecosystem evolution, to which we best adapt.
We don’t know when our present existence is threatened how much and
how rapidly biodiversity is degraded, but there should be some number
(not easily predicted). The same is true for our society; our life
is dependent on the present social system — a product of social
evolution, to which we best adapt. We don’t know when our present
world is threatened how much and how rapidly social system is degraded.
These two problems are alike, both arising from a complex adaptive
system. Complex social systems could amplify the effect of a minor
mortality.Time-scales also play a role. If any change is slow enough, we
can, or ecosystem would adapt to a new form. If the change is rapid
enough, they may fail. There is a simple physical analogy; the
adaptation of gas is limited by the sound speed. If change goes
faster than the sound speed, the gas fails to adapt — the net result
is a well-known supersonic shock. The same would be true for our
society. If the spread of the pandemic is rapid enough, our system
would fail to adapt. Of course, with the advent of the internet,
we have a better chance of adaptation before the wave comes. But the
expected result of adaptation is so drastically different from the
current social system, the arrival of pandemic flu will trigger
a reaction that looks like to change the world overnight.
I’m skeptical about such a drastic change in social systems could be
done overnight (even officials declare “immediately”), since no one
is accustomed to the change, and expect the situations something
between adapted (with a drastic change) to less-adapted (little
reaction before the wave reaches, and an immediate panic is
triggered).Post edited by: martin, at: 2006/02/02 00:49
Just seen on Reuters (! – shows that haven’t watched or listened to local news today):
Quote:HONG KONG (Reuters) – The Hong Kong government said on Wednesday that two dead birds — a wild crested myna and a domestic chicken smuggled in from mainland China — had tested positive for the deadly H5N1 bird flu virus. … The chicken and myna double the number of dead birds Hong Kong government tests in the past two weeks have shown to have H5N1, a strain of bird flu that has killed 85 people worldwide since late 2003. As a precaution, the government will cull all poultry within five kilometres (3.1 miles) of the smallholding where the chicken died, and also close the city’s walk-in aviaries and a large nature reserve, said Thomas Sit, Acting Assistant Director of Agriculture, Fisheries and Conservation. It was unclear where the chicken caught the deadly disease, said Thomas Tsang, Consultant of the Centre for Health Protection of the Department of Health. "We do not know whether the chicken was infected in the mainland or whether it was infected in Hong Kong," he told a news conference. "We can’t really draw any conclusions yet." The bird was smuggled into Hong Kong on January 26 without symptoms and became ill on January 31. The typical incubation period for the disease in birds is two to 10 days, he said. The chicken was brought illegally into Hong Kong ahead of the Lunar New Year period. Despite bird flu worries, the government increased the number of chickens shipped into Hong Kong from mainland China around the January 29 Lunar New Year. It fell ill and died about a half a kilometre (0.3 miles) from the border with China in an area where the government said on Sunday that an Oriental Magpie Robin also died of H5N1. The dead crested myna was found in an urban playground, Tsang said.Hong Kong says found more H5N1 flu in dead birds[/url] Just found govt press release; the mynah was found in Wong Tai Sin, north Kowloon (not quite in New Territories; over 10km south of where 1st infected magpie robin found, which in turn another 10km south of place on border where 2nd magpie robin and now the smuggled chicken found). http://www.info.gov.hk/gia/general/200602/01/P200602010235.htm Crested mynah not much of a cage bird here; common resident. So, less likely to me that seeing infections in captive [wild] birds. Feeding at places with chickens? – can but guess. Govt to close aviaries and Mai Po Marshes Nature Reserve as precaution. Later thought re Wong Tai Sin: there’s big temple there; major place during Chinese New Year celebrations. Just wondering if the mynah found at Wong Tai Sin might have been part of batch released at the temple – for good fortune – over Chinese New Year; googled, and found (example of this) re last governor Chris Patten visiting the temple some years ago: " He helped release 108 birds from nine cages as part of a ”setting free ceremony” to seek blessing for the well-being of the Hong Kong people."
Chicken smuggling by no means uncommon, inc at Shataukok:
Quote:At 5.10 am this morning (May 30), a public light bus running between Sha Tau Kok and Sheung Shui was also intercepted at the above Check Post. Customs officers arrested a 72-year-old female passenger; and seized a total of 10 kilograms of chicken and five kilograms of duck, valued at about $340, onboard.(May 30, 2005) http://www.customs.gov.hk/eng/new_release_20050530_smuggled_pork_e.html
Quote:A total of 429 kg of fresh chicken, 37 kg of fresh duck and 18 kg of fresh goose have been seized. Other than fresh meat, two live chickens were seized and a person was arrested at the Sha Tau Kok Control Point yesterday(February 7, 2005). http://www.customs.gov.hk/eng/new_release_20050208_smuggling_of_poultry_e.html
Quote:Enforcement actions on examining imported cargoes and baggage were stepped up. As a result, 211 kg of fresh chicken, 7kg of fresh duck and 3.5kg of fresh goose were seized.(4Feb05) http://www.customs.gov.hk/eng/new_release_20050204_curb_meat_smuggling_e.html
Quote:Following the seizure of pork and chicken made on January 31, Customs officers of the Shek Chung Au Check Post of the Sha Tau Kok Control Point today (February 3) seized four bags of pork and chicken weighing 68 kg onboard a public light bus running between Sha Tau Kok Village and Sheung Shui.http://www.customs.gov.hk/eng/new_release_20050203_smuggled_pork_chicken_e.html
A second dead magpie robin has tested positive, in village near border with Shenzhen, mainland China.
Given their behaviour, and fact these villages some km apart, unlikely they were in contact in wild; odd that no other species yet found in Hong Kong with H5N1 this winter.So, my guess still that they were captive birds; maybe a bird dealer or two has problems (and – yes, another guess – has tossed birds out; not as tho a dealer wants hassle from authorities).
[Emailed Agric, Fisheries and Cons Dept here re this – have they examined the birds to see if signs of captive origin; no reply as yet.]Results from 1st bird show the H5N1 related to prevalent strains in mainland China poultry.
from email to conservation/h5n1 forum:
Quote:In last days fears and allegations against wild birds piled up in Bulgarian media.First in central national newspaper a professor from the Academy of
Sceiences (graduate from russian academy)announced how the Russian scientist have confirmed that the Common Pochard Aythya ferina spead the virus from SE Asia through Siberia to Novorosiisk (Russia) and now is carrying it towards Bulgaria.Second in Saturday in the same newspaper another scientis (though not an ornitologis but parisotologist this time) made a map conviniently showing main migration routes in Bulgaria with vicinity of large wetlands making the allegation that these are the sites where the Ai will appear first in Bulgaria.
These allegations then were fueled by the death of some 70 to 100 Coots
(Fulica atra) along major wetlands in North Bulgaria – Shabla and Durankulak Lakes and Burgas wetlands complex. Though the vets said that thers is no confirmation of AI presence in the birds all daed bodies were buried in the ground by authorities and the municipality declared that Durankulak and Shabla lakes are plague zones of death. So the blame has been announced and now our voice is not very well heard among those as journalist are looking for senssations while we try to say the facts and truth.15:33 31Jan2006 RTRS-Romanians torture and kill wild birds near Danube
BUCHAREST, Jan 31 (Reuters) – Romanians have been torturing and
killing wild birds stranded by freezing weather close to where the
country’s first bird flu outbreak was detected in October, a wildlife
organisation said on Tuesday.
“Around 15 young men, aged between 20 and 25, were catching the
birds, throwing them in the air, using birds which were still living as
soccer balls, and tearing off their heads,” Razvan Popescu, director of
the Oceanic Club wildlife protection organisation told Reuters.
The birds had been too cold and tired to fly as temperatures
plummeted as low as minus 20 Celsius near the Danube delta.
“There were up to 100 migratory birds, ducks, geese and coots,”
Popescu said.
He said the Oceanic Club had been doing checks on migratory birds as
the lakes and rivers froze when they saw the men playing with the birds.
Veterinarians said samples were taken from some of the dead birds
and tested for bird flu. They came out negative.
Romania has found avian flu in poultry in 26 villages since October,
but has recorded no human cases.
Health Ministry officials said doctors were now monitoring the men
because many of the people who have contracted bird flu worldwide had
had close contact with infected birds.
((ROMANIA-BIRDS; Reporting by Aurora Martiniuc; Writing by Antonia
Oprita; Editing by Alison Williams; Reuters Messaging ))Environmental police have been contacted; some measures being taken to avert repeats of such woeful lunacy.
comments re this grebe and some other wild birds in Russia that were reported to have H5N1
First by Richard Thomas of Birdlife International;Quote:> >[Readers are referred to 2 drafted scientific papers from the D.I.
> >Ivanovsky Institute of Virology, Russian Academy of Medical Sciences. The
> >papers have been opened for discussion at:
> >.
> >
> >The papers include details on “indication of influenza A/H5N1 virus by
> >RT-PCR of cloaca/trachea samples” from 5 species of wild birds “without
> >clinical features”, collected near the center of the epizootic in the
> >Novosibirsk region (July 2005).
> >
> >The birds were: Mallard (_Anas platyrhynchos_), 6/12 positives; Pochard
> >(_Aythya ferina_), 12/33 positives; Great crested grebe (_Podiceps
> >cristatus_), 1/2 positive; Coot (_Fulica atra_), 0/5 and Common tern
> >(_Sterna hirundo_), 0/2. Out of a total of 54 non-clinical wild birds, 19
> >(35.2 percent) were positive.
> >
> >The papers also report the isolation of the A/H5N1 strain
> >A/Grebe/Novosibirsk/29/05 from a Great crested grebe “without clinical
> >features”, collected near the center of the epizootic in the Novosibirsk
> >region (July 2005). – Mod.AS]
>
> I strongly urge you to read the above papers – and please comment.
Needless to say the blame is laid firmly and squarely on wild birds. There’s
some very important information lacking from the papers, but some very
interesting information included too.
>
> Particularly lacking is any indication as to how the poultry and wild
birds came into contact. I also couldn’t see any indication of timescales of
the episode: clearly poultry were dying before wild birds became infected,
and it is stated many wild birds later died, but it doesn’t say how long
afterwards.
>
> I am particularly amazed to see that just over a third of the wild birds
tested were positive (more than 95% of the poultry were positive). There is
some analysis of the genetic strains involved. Of particular interest is
that the strain in poultry is said to be very close to the Qinghai strain.
This means that the strain from the Qinghai area was transported to
Novosibirsk by some means. Given the location, time of year and lack of
spread in other directions from the Qinghai area, wild bird
migration–whilst it can’t be ruled out–would seem to be highly unlikely.
>
> Hence, poultry or something that had come into contact with infected
poultry/faeces in the QInghai area is far more likely. A quick look at the
atlas and you will see Novobirsk is on a railway connection to Lanzhou, the
large city close to Qinghai.
>
> Interestingly, FAO has reported Lanzhou as the source of an avian
influenza outbreak in Lhasa, in January 2004 – hence there is already a
precedent for long distance movement of infection from the Qinghai region
(Lanzhou to Lhasa is 1,500 km). The Lhasa outbreak was actually at a poultry
market. [Imagine if those birds hadn’t died at the Lhasa market, but had
been bought by several farmers/local people in the region. We’d have a
sudden near simultaneous outbreak across farms/backyard chickens in Tibet. I
wonder where the blame for the outbreak would be placed?]
>
> There is no indication in either paper as to whether the poultry involved
were recently transported to Novosibirsk, bred locally or purchased at a
poultry market supplied from elsewhere. This should be investigated, as
should other possible links – perhaps through infected animal/fish-farm
feed. I’m sure you’ll not be surprised to learn that Lanzhou is a major
producer of feed too.
>
> Cheers
> Richarda response to this, from a virologist:
Quote:I am afraid one possiibility for many positives in the wild bird species is cross contamination and false positives when PCR alone is used to identify infection. An aliquot of the cloacal sample could be sent to another laboratory for verification.Post edited by: martin, at: 2006/01/30 07:43
Quote:> The grebe was ‘collected’ on 28 July 2005 at a location where poultry had
> been dying of avian influenza since 15 July.
>
> The grebe was a juvenile and is reported to have shown no clinical
> symptoms of the disease.
>
> Subsequently hunters reported mass death of wild birds in the area.
>
> The obvious explanation — given the timing of the above and the fact the
> bird was a juvenile — is because the grebe had just been infected from
> a poultry source and hadn’t yet succombed to the virus when collected.Although the above explanation looks most obvious, there may be yet
another possibility. If the bird was “collected” in live, it may have
been infected during handling (after vet’s exposure to poultry).
Since this was still in the early stage of Russian outbreaks, local
vets may have not been yet aware of how contagious this virus is.
We probably need to be extremely careful in interpreting “healthy wild
bird tested positive”.Both vets and ornithologists should pay specialattention not to become “vectors” to wild individuals — this point is generally missing in guidelines (some only refer to prevention of human infections), and would be especially advisable to newly introduced areas or countries.
from correspondent re point 4 in above post:
Quote:Perhaps I understand the background more correctly. The asteroid
impact threat was not a final target of the study, but it was more
important that the same research tools (wide-field automated telescopes
and pipeline analysis) can be applied to different targets of
academic interest. They will not be very appealing (at least for
the beginning) to the public. The NASA people needed a different,
more popular target in pursuit of their original scientific interest.
These telescopes are now being used to rapid follow-up observations of
gamma-ray bursts, recovery of dead comets, and other targets of current
popular astronomy problems. The “blue book” of the Hubble Space
Telescope was similar, but produced far greater results than originally
expected.I don’t know whether influenza specialists are taking the similar
course, or they regard pandemic a real, foreseeable threat. But
as far as I read, top virologists look like to have been more
deliberate, and have warned the public against alarmism. I think
that these people regard it a real threat, and urge governments
to prepare for the “upper limit” disaster. They probably think it
insufficient to prepare for the “expected mean” (as might be derived
from evolutionary biology).“The said overview – H5N1 Outbreaks and Enzootic Influenza – might have been written prior to the westward spread of H5N1 and its detection in Romania, Turkey, Crimea and Croatia. “
Yes, it might.
And since the said overview, have you also noted re no H5N1 outbreaks on the migration routes of birds from Qinghai; nor elsewhere in Asia (ex-Russia)?
Also that birds affected in east Europe evidently not from areas known to have H5N1 during spring/summer 2005?
– eg, Croatian swans of “west European” origin.
Other waterbirds sharing ponds with the Croatian swans apparently not infected – several tested, but no H5N1. Maybe as tests also indicated low levels of excretion by swans.Other than Qinghai, it appears it is far from easy for this virus to transmit among wild birds: several instances of infected birds being found at places with numbers of waterfowl (eg tens of thousands in HK), yet no sign of spread.
Does seem, though, it’s pretty easy to spread among Robert Webster’s experimental ducks.
And can then do some hand-waving “science” to say it therefore spreads readily among wild birds, and engage in fear mongering for Africa, Afghanistan etc etc.Just come across blog post by John Hawks, Assistant Professor of Anthropology at the University of Wisconsin—Madison; on the arguments between Ewald and Revere.
He notes:
Quote:1. Almost no mainstream press accounts of the bird flu threat discuss anything about the evolution of influenza. This is probably the most important public impact of evolutionary theory today, but we hear almost nothing of the evolutionary modeling of how the virus may change.2. Ewald is very well known for studying the evolutionary dynamics of disease. He is making an argument that is sound, as far as the dynamics of selection are concerned. Thus, there are good reasons to think that the worst will not happen, and this is a perspective that has been underplayed.
3. So far, the theory has only been tested by a relatively small number of instances — there just haven’t been so many pandemics that we can infer accurately from past events what the future will be like. It could certainly happen that some new influenza strain could violate the model in some unexpected way, and for this reason governments should play it safe rather than assume that no high-virulence pandemic will emerge.
4. A lot of public health scientists are going to be well-employed for as long as the bird flu remains in the public perception. This doesn’t mean that they are wrong to convey alarm, but it does mean that they don’t benefit by playing down the threat. It’s sort of like NASA and the asteroid impact threat — partly they are more concerned because they know more about the threat and its terrible effects, partly because it’s their job to be concerned.
5. There are a lot of biologists who don’t use or understand selection.
Ewald bird flu spat
Editorial January 23: The Bird Flu Flap concludes:
Quote:Heed the warnings, but don’t take them too seriously. There are other more pressing problems for us to worry about. However, if you do feel the urge to follow the Government’s premature survival tips, perhaps rather than packing a new survival kit it may just be easier to cheat a bit – drag out the one you prepared in 1999 for the Y2K bug.From NZ Herald:
Quote:The government’s preparations for a possible outbreak of bird flu are being panned as being completely over the top.This week the Ministry of Health began distributing leaflets explaining how New Zealanders should prepare for a possible pandemic.
It is already stockpiling shots of the ant-viral drug Tamiflu.
But Macquarie University professor Peter Curson, from Australia, said New Zealand is getting into a flap over nothing.
He said the government is reacting to something that is very unlikely to happen.
Peter Curson said the country would be better off declaring a pandemic of some the real health problems it has, like diabetes and obesity.
Australian academic mocks our bird flu ‘over-reaction’
Post edited by: martin, at: 2006/01/23 01:39
Are idiots running amok at high levels of the FAO?
from a recent news release,
http://www.fao.org/newsroom/en/news/2006/1000215/index.htmlQuote:Bird flu virus could spill over to Africa and Europe in springtime
Fighting the disease in animals is crucial to win the battle against the
virus
18 January 2006, Beijing – The avian influenza virus … could be further spread by migratory birds particularly coming from Africa in the spring, the UN Food and Agriculture Organization (FAO) warned today.– this despite paucity of evidence that wild birds can sustain and spread H5N1
– and no evidence there is H5N1 in AfricaStill fingering wild birds perhaps convenient for FAO, perhaps avoiding any highlighting of potential problems resulting from integrated farming practices, such using chicken manure as feed and fertiliser in fish farms – which have been extensively promoted by, err, the FAO.
Tongue-in-cheek commentary in Huffington Post, Bill Robinson: The Bird Flu Is A Cock-Tease includes:
Quote:I am totally disappointed in the bird flu. And I’m not the only one. The fear-based 24 hour news networks, not to mention the Bush administration, are enraged they have nothing to scare us with at the moment. No credible terrorist threats, no escaped inmates, no missing cheerleaders in Aruba. So they have great hopes for the H5N1 virus… what better way to create Must-See-CNN, or a helpless, childlike devotion to our Big Brother Government?But Dr. Sanjay Gupta is looking worried these days. His bleached smile just isn’t as wide. Why? The damn thing isn’t mutating. Sure, it’s killed about 70 people… but for a virus that’s been around for 9 years, that ain’t saying much. By way of comparison, more people were killed by police stun guns during that time, more people died at the hands of Australia’s Dr. Patel (aka Dr. Death!), and, of course, more Americans die in a typical month in Iraq.
Obviously, the threat (code Orange, anyone?) is in the possibility of a sudden pandemic, which we’re repeatedly told we’re “overdue” for. The problem is, we’re not. Deadly pandemics seem to obey the same rules as roulette– your number doesn’t have to come up once every “cycle.” And the government’s no better at predicting them than they are at tsunamis or earthquakes. They’re better at forecasting hurricanes… even if they lose a major city every now and then.
In May, Health and Human Services Secretary Mike Leavitt said the virus that causes bird flu “could become one of the most terrible threats to life that this world has ever faced.” That was 8 years after the virus was detected, but apparently May, 2005 is when Mike got the memo. Since that time, billions of dollars for pharmaceuticals and vaccines have been pledged by international governments, always deferring to the Americans– the ” CDC’s projections.”
Funny thing about projections– they’re notoriously wrong. In 1997, the same year the bird flu virus was discovered, a leading UK research group projected that vCJD, the human form of mad cow disease, would kill up to 10 million people. In 2002 they revised that downwards to 50,000. More recently, ummmm….. 80. And that’s over the next 75 years. Probably didn’t catch that story on Rita Cosby.
None of this is to minimize the 70 or so people who have died from this awful virus. But as Beverly Hills housewives are hording Tamiflu, it might be helpful to keep in mind those 70 people were living in developing countries, where poultry and pigs are literally raised in the house.
…
Of course, none of that is what TV networks want us to hear. They need us locked in the anxiety spiral, eager to consume whatever soothing product is advertised during the commercial break–perhaps an antidepressant or sleeping aide, brought to you by the company making the non-existent vaccine for the bird flu. Follow the money, wasn’t that the phrase?As Wolf Blitzer anxiously stands before his 10 (live!) plasma screens in “The Situation Room”, like the host of a telethon waiting for someone to invent the disease, you can practically hear the desperation in his voice for this lame-ass virus to do something other than kill turkeys in Turkey. He’s acutely aware another Y2K would be bad for business.
…
If there’s any silver lining to the rabid marketing of the bird flu, it’s this: If you really want something to be terrified of, just take a look around. You’ve already got it.Post edited by: martin, at: 2006/01/21 04:05
So, maybe ironic that after I posted the above, a dead magpie robin in Hong Kong tests positive.
But hasn’t caused panic.And yes, Helen – the ignorance, fuelled by massive disinformation, is astonishing, and deeply sad.
It’s astonishing isn’t it. What concerns me, are the people who stop feeding birds through sheer ignorance.
The up side, is they stop buying the intensively farmed chicken in the supermarkets, through fear of “catching that bird flu thing”. Hopefully, though I know rather naievely, lack of demand will lead to less intensive farming. ok, I thought not….
and in southwest China:
Quote:Since 1985, more than 20 thousand red beak seagulls [= common black-headed gulls] travel from Siberia to the southern Yunnan city of Kunming to spend the winter. There, they are given food from the locals and they’ve been an indispensible part of the local life.But this year, the fear of bird flu has made people hesitate getting close to the lovely birds, and more than 8000 birds have flown away due to the lack of food.
But, a test on the dead bird shows that it had starved and wasn’t carry the deadly virus.
Now for the remaining more than 10,000 birds, the following three months is a critical time during which they need to have enough food to prepare for their long migration back to Siberia.
The paper says many citizens cried at hearing the death of the bird, and they say they will again come out to provide food for their city’s precious guests.
Red Beak Seagull Starved due to Bird Flu Fear
Scaremongering re wild birds and H5N1 claims another victim.
So deeply sad that so many people have become scared of wild birds.
