Study: Migratory birds not to blame for spread of avian flu

[AlaskaDenise]

Nitin Sethi
[ 15 Apr, 2007 0025hrs IST

TIMES NEWS NETWORK ]

NEW DELHI: The evidence is finally out to disprove minister of state Kanti Lal Bhuria's statement in Parliament that migratory birds could be blamed for the spread of the virulent bird flu.

Two research papers published in the journal 'Ibis' have concluded that there is no evidence to link the recent spread of the pathogenic avian influenza to migratory birds. The paper concludes that commercial activities, particularly those associated with poultry, are the major factors that have determined the global spread of the deadly virus.

The report only corroborates the tests done in India by the Bombay Natural History Society, the environment ministry and the Bhopal high security lab which have not found a single infected wild bird till date. One of the two papers presents evidence that if migratory wildfowl were a key agent of the virus, then the migratory birds that travel from Central Asia would have carried the virus into India, Pakistan and Bangladesh besides other countries.

Bar-headed geese, brown headed gulls and great black headed gull were all found dead, infected with the virus in China and even though all these birds migrate to India in the winters, not a single case of infection was traced in India. This proves the fact that wild migratory birds are incapable of carrying the virus over large distances.

If migratory birds had been the cause of inter-country spread, then, the paper suggests, they would have become the carriers in several regions depending on their migratory pattern. But no such correlation was found between the direction of the onward spiral of the virus and the migratory routes of the birds.

The authors explained that migratory birds like ducks and waders travel several hundred kilometres in a single day.

http://timesofindia.indiatimes.com/...r_spread_of_avian_flu/articleshow/1911464.cms

 

[sharon sanders]

Re: Study: Migratory birds not to blame for spread of avian flu

More here -

http://www.flutrackers.com/forum/showthread.php?t=19893&highlight=ibis

 

[HenryN]

Re: Study: Migratory birds not to blame for spread of avian flu

Nitin Sethi
[ 15 Apr, 2007 0025hrs IST

TIMES NEWS NETWORK ]

NEW DELHI: The evidence is finally out to disprove minister of state Kanti Lal Bhuria's statement in Parliament that migratory birds could be blamed for the spread of the virulent bird flu.

Two research papers published in the journal 'Ibis' have concluded that there is no evidence to link the recent spread of the pathogenic avian influenza to migratory birds. The paper concludes that commercial activities, particularly those associated with poultry, are the major factors that have determined the global spread of the deadly virus.

The report only corroborates the tests done in India by the Bombay Natural History Society, the environment ministry and the Bhopal high security lab which have not found a single infected wild bird till date. One of the two papers presents evidence that if migratory wildfowl were a key agent of the virus, then the migratory birds that travel from Central Asia would have carried the virus into India, Pakistan and Bangladesh besides other countries.

Bar-headed geese, brown headed gulls and great black headed gull were all found dead, infected with the virus in China and even though all these birds migrate to India in the winters, not a single case of infection was traced in India. This proves the fact that wild migratory birds are incapable of carrying the virus over large distances.

If migratory birds had been the cause of inter-country spread, then, the paper suggests, they would have become the carriers in several regions depending on their migratory pattern. But no such correlation was found between the direction of the onward spiral of the virus and the migratory routes of the birds.

The authors explained that migratory birds like ducks and waders travel several hundred kilometres in a single day.

http://timesofindia.indiatimes.com/...r_spread_of_avian_flu/articleshow/1911464.cms

As I said, the conservation groups have found ZERO live birds with H5N1. The propaganda campaign is in high gear. Lots of false negatives followed by utter nonsense (including dead birds don't fly).

Prior to Qinghai Lake in May, 2005, no country west of China had H5N1. After Qinghai Lake ALL countries west of China with H5N1 have Qinghai H5N1.

The story is in the seqeunce, and it could not be clearer. For the 40 some odd countries west of China (in Asia, Africa, the Middle East, and Europe) who discovered H5N1 (in the past 2 years), ALL HPAI H5N1 has been Qinghai (Clade 2.2).

 

[AlaskaDenise]

Re: Study: Migratory birds not to blame for spread of avian flu

Given the widely publicized situation of Indian testing resources being overwhelmed; and sample contamination and degradation, I don't see how anyone could be so certain there was no BF in India.

These types of reports are dangerous. People will not practice proper biosecurity and most important - not be open to the possibility of a wide variety of vectors.

I really admire migratory birds, but it's important to be realistic about their roles in a wide variety of ecological & environmental issues.

I fear the problem may be worse if pets become widespread vectors - birds, cats, dogs, etc.

If we cannot be certain about the source and "unknown vectors" of 1918 influenza, how can anyone be so certain about a new influenza, while it's in its infancy?

.

 

[HenryN]

Re: Study: Migratory birds not to blame for spread of avian flu

Given the widely publicized situation of Indian testing resources being overwhelmed; and sample contamination and degradation, I don't see how anyone could be so certain there was no BF in India.

These types of reports are dangerous. People will not practice proper biosecurity and most important - not be open to the possibility of a wide variety of vectors.

I really admire migratory birds, but it's important to be realistic about their roles in a wide variety of ecological & environmental issues.

I fear the problem may be worse if pets become widespread vectors - birds, cats, dogs, etc.

If we cannot be certain about the source and "unknown vectors" of 1918 influenza, how can anyone be so certain about a new influenza, while it's in its infancy?

.

Actually, the data are quite easy to interpret. Those who rely on negative data for their arguments have no argument.

The fallure to find Qinghai H5N1 in live birds is almost all location where where H5N1 is, west of China speaks volumes.

Most scientists who get negatives on every test that they run, begin to question the test, long before 20,000 negatives. These groups instead put out media reports and psuedo science for the masses on how many negatives they generated.

 

[canagica]

Re: Study: Migratory birds not to blame for spread of avian flu

The fallure to find Qinghai H5N1 in live birds is almost all location where where H5N1 is, west of China speaks volumes.

Most scientists who get negatives on every test that they run, begin to question the test, long before 20,000 negatives. These groups instead put out media reports and psuedo science for the masses on how many negatives they generated.

It seems like there are two issues here, both of which are being missed in the current discussion: if the AI test given to these live birds was the wrong one to give, then I would expect to see some discussion of the test's efficacy in the discussion (in the Ibis critical review they say "the lack of tracheal sampling may explain the lack of detection in wild birds"); also, if the results were completely suspect, then it likely wouldn't even get published.

So-is it pseudoscience to report on the results of studies? In my opinion, no. And if we are going to indict scientific journals as being mouthpieces of ulterior motives, then IMO I would fear the propaganda-generating ability of the pharmaceutical companies a whole lot more than a that of a bunch of bird-nerds.

The second issue has to do with media reports: scientists have very little control over the story that a journalist/editor wants to tell, and caveats and objectivity can get in the way of a good story. This isn't to indict the journalists, but rather to say that the story the media crafts can be different without the supporting information that is contained in a paper.

So what have we learned from these published studies and reviews?

1. If the sampling isn't systematically flawed, H5N1 is extremely rare in wild birds (only found in a few asymptomatic ducks in China).

2. If the sampling is fatally flawed, then we know little more than we did before these studies.

3. The relative efficiencies of various tests should be tested to determine the best tests to use for H5N1.

4. The rarity of finding H5N1 in wild birds is consistent with a set of hypotheses that find legal and illegal trade as primary long-distance drivers of H5N1 dispersal, with migratory birds playing a secondary role (as in the European outbreaks).

5. Negative data are data, and until positive data are found, we are left to interpret them as best we can.

In this case, Dr. Niman, it would be handy to see some references about testing efficiencies in order to understand whether your critique of the tests being done is accurate, and to understand whether option 1 or 2 (above) are the best way of interpreting them.

 

[HenryN]

Re: Study: Migratory birds not to blame for spread of avian flu

It seems like there are two issues here, both of which are being missed in the current discussion: if the AI test given to these live birds was the wrong one to give, then I would expect to see some discussion of the test's efficacy in the discussion (in the Ibis critical review they say "the lack of tracheal sampling may explain the lack of detection in wild birds"); also, if the results were completely suspect, then it likely wouldn't even get published.

So-is it pseudoscience to report on the results of studies? In my opinion, no. And if we are going to indict scientific journals as being mouthpieces of ulterior motives, then IMO I would fear the propaganda-generating ability of the pharmaceutical companies a whole lot more than a that of a bunch of bird-nerds.

The second issue has to do with media reports: scientists have very little control over the story that a journalist/editor wants to tell, and caveats and objectivity can get in the way of a good story. This isn't to indict the journalists, but rather to say that the story the media crafts can be different without the supporting information that is contained in a paper.

So what have we learned from these published studies and reviews?

1. If the sampling isn't systematically flawed, H5N1 is extremely rare in wild birds (only found in a few asymptomatic ducks in China).

2. If the sampling is fatally flawed, then we know little more than we did before these studies.

3. The relative efficiencies of various tests should be tested to determine the best tests to use for H5N1.

4. The rarity of finding H5N1 in wild birds is consistent with a set of hypotheses that find legal and illegal trade as primary long-distance drivers of H5N1 dispersal, with migratory birds playing a secondary role (as in the European outbreaks).

5. Negative data are data, and until positive data are found, we are left to interpret them as best we can.

In this case, Dr. Niman, it would be handy to see some references about testing efficiencies in order to understand whether your critique of the tests being done is accurate, and to understand whether option 1 or 2 (above) are the best way of interpreting them.

Nonsense. H5N1 is widespread in wild birds including Africa, where these studies found ZERO positives.

The negative data is nonsense, much like the above "conclusions".

Actually, the latest EID report shows H5N1 in multiple countries in Africa, the Middle East, and Europe, and ALL are the Qinghai stain.

 

[canagica]

Re: Study: Migratory birds not to blame for spread of avian flu

Nonsense. H5N1 is widespread in wild birds including Africa, where these studies found ZERO positives.

The negative data is nonsense, much like the above "conclusions".

Ouch-i thought those conclusions were sort of logical, given the available field data. So-just to make sure I understand what you're saying, I'm going to restate your points in my own words (sort of joking, sort of not ):

1. H5N1 is widespread in migratory wild birds across the world: we know this because it is almost never found by the incompetent, propagandizing, data-poor "conservation groups" (does this count have positive data?).

2. The patiently argued conclusions of anyone suggesting anything else can be dismissed with a brisk wave of the hands and one word: "nonsense".

This truly advances our understanding. Thanks.

But seriously, if it were widespread in migratory birds, wouldn't there be a whole lot more coordination in outbreaks (both poultry and wild birds) spread across a greater area? That is ultimately the question being asked when the Ibis review concluded that the pattern of outbreaks didn't match with what we know about migratory routes.

This is the pattern that happened in the widespread European outbreaks (thought to be one of the better examples of a migratory bird-driven H5N1 dispersal event), where waterfowl were forced south by cold weather. Why don't we see similar coordinated outbreaks across northern Africa, west Africa, Indonesia/Phillipines, Japan, etc.? The European outbreaks had a wide variety of dead wild birds that were positive for H5N1, sans outbreaks in poultry operations, which was suggestive even without the cold weather.

Is it possible that we know less about H5N1 Qinghai than perhaps we think we do? Why would the only method to transport it be migratory birds, when there have been concrete examples of other (non-mutually exclusive) routes of dispersal?

And why is it that many of these sites that lie along migration pathways and that have little or no H5N1 just happen to have very stringent import regulations on poultry, caged birds, etc? It also is suggestive that trade controls do have an influence on the likelhood of BF breaking out. Am I arguing that birds don't have a role? No. Just that there are other important factors to consider.

I'd like to think that we are posting in order to further our understanding of the issues and that people are learning things from these forums (as the FT mission statement aims), and unsupported one-liners about "nonsense" don't really accomplish that, and are dangerous oversimplifications, IMO.

 

[HenryN]

Re: Study: Migratory birds not to blame for spread of avian flu

POSITIVE data was just released on H5N1 throughout Europe and Africa, which has also been posted here

http://www.flutrackers.com/forum/showthread.php?t=21282

ALL were H5N1. This "debate" ended in the summer of 2005 when Qinghai was found in Russia, Mongolia, and Kazahstan.

What followed was a propaganda campaign, based solely on negative data (as in nonsense).

It is remarkable that the nonsense continues.

 

[canagica]

Re: Study: Migratory birds not to blame for spread of avian flu

POSITIVE data was just released on H5N1 throughout Europe and Africa, which has also been posted here

http://www.flutrackers.com/forum/showthread.php?t=21282

ALL were H5N1. This "debate" ended in the summer of 2005 when Qinghai was found in Russia, Mongolia, and Kazahstan.

What followed was a propaganda campaign, based solely on negative data (as in nonsense).

It is remarkable that the nonsense continues.

Given that the authors of the study you reference point a finger first at trade for this widespread dispersal (and only secondarily at migratory birds), where does it sit on the easy-to-interpret vs. propaganda continuum?

A quote from an interview with the lead author from this TerraDaily dispatch:

"The migratory pathways of wild birds don't correspond with the movement of the genomes that we sequenced," said Salzberg. "Humans carry chickens between many of the countries in our study, often transporting them across great distances. That and the weak biosecurity standards in most rural areas point to human-related movement of live poultry as the source of the introduction of H5N1 in some countries."

 

[HenryN]

Re: Study: Migratory birds not to blame for spread of avian flu

Given that the authors of the study you reference point a finger first at trade for this widespread dispersal (and only secondarily at migratory birds), where does it sit on the easy-to-interpret vs. propaganda continuum?

A quote from an interview with the lead author from this TerraDaily dispatch:

"The migratory pathways of wild birds don't correspond with the movement of the genomes that we sequenced," said Salzberg. "Humans carry chickens between many of the countries in our study, often transporting them across great distances. That and the weak biosecurity standards in most rural areas point to human-related movement of live poultry as the source of the introduction of H5N1 in some countries."

Handwaving at its best. ALL isolates were Qinghai and transported and transmitted by migratory birds. NONE of the countries west of China had H5N1 prior to Qinghai Lake. The lead author was from bioinformatics and "discovered" that Qinghai was different (which was known in July, 2005).

 

[HenryN]

Re: Study: Migratory birds not to blame for spread of avian flu

Handwaving at its best. ALL isolates were Qinghai and transported and transmitted by migratory birds. NONE of the countries west of China had H5N1 prior to Qinghai Lake. The lead author was from bioinformatics and "discovered" that Qinghai was different (which was known in July, 2005).

Most countries in Europe also have not reported H5N1 in domestic poultry, yet ALL HPAI H5N1 isolates in the DEAD wild birds in Europe are Qinghai (as are the dead wild birds in the Middle East and Africa).

 

[Mamabird]

Re: Study: Migratory birds not to blame for spread of avian flu

If I may add a bit to the discussion, or perhaps to the confusion, it is well known that wild, migratory birds are known to have been infected by highly pathogenic H5N1 and survived for long periods of time. In fact, some duck species are asymptomatic with high path H5N1, but can excrete high quantities of the virus throughout the waterways they frequent. On the other hand, by definition, chickens do not survive highly pathogenic H5N1. Some live 24 to 48 hours, but they all succomb.

Given those well known facts (see CDC and WHO web sites), wouldn't it seem more plausible for highly pathogenic H5N1 to travel long distances on the wings of migratory fowl, rather than domestic poultry. Unless we are talking about the illegal transport of very dead chickens, it seems to me that H5N1 movement by land is substantially limted by its pathogenic affects on poultry.

 

[gsgs]

Re: Study: Migratory birds not to blame for spread of avian flu

some few chickens might survive ... when they are not culled.
Some few chickens might be asymptomatic carriers of H5N1.

Some asymptomatic ducks might have detectable H5N1 in throat swabs
or fecal swabs , some other maybe only (temporarily) have H5N1 in
other organs. And it might later become symptomatic or
swab-detectable triggered by unknown circumstances.

 

[HenryN]

Re: Study: Migratory birds not to blame for spread of avian flu

If I may add a bit to the discussion, or perhaps to the confusion, it is well known that wild, migratory birds are known to have been infected by highly pathogenic H5N1 and survived for long periods of time. In fact, some duck species are asymptomatic with high path H5N1, but can excrete high quantities of the virus throughout the waterways they frequent. On the other hand, by definition, chickens do not survive highly pathogenic H5N1. Some live 24 to 48 hours, but they all succomb.

Given those well known facts (see CDC and WHO web sites), wouldn't it seem more plausible for highly pathogenic H5N1 to travel long distances on the wings of migratory fowl, rather than domestic poultry. Unless we are talking about the illegal transport of very dead chickens, it seems to me that H5N1 movement by land is substantially limted by its pathogenic affects on poultry.

Yes, you are correct.

Unfortunately, H5N1 analysis is heavily influenced by politics and agendas, and no science or logic is required.

 

[Mamabird]

Re: Study: Migratory birds not to blame for spread of avian flu

"The migratory pathways of wild birds don't correspond with the movement of the genomes that we sequenced," said Salzberg. "Humans carry chickens between many of the countries in our study, often transporting them across great distances. That and the weak biosecurity standards in most rural areas point to human-related movement of live poultry as the source of the introduction of H5N1 in some countries."

Questions for all to ponder: Assuming that the transport of chickens is the cause for widespread infections of H5N1 to Europe and Africa, does this mean that:

1. Humans only recently began carring chickens over great distances? Or
2. Humans have always been carrying chickens over great distances, but biosecurity has only recently become weak?

If the answer to either question is "no", then why haven't we seen highly pathogenic H5N1 infections much earlier in Europe, Russia and Africa? After all, it has been around for some time now in poultry in Asia, and poultry to poultry infections occur quite easily.

 

[Mamabird]

Re: Study: Migratory birds not to blame for spread of avian flu

some few chickens might survive ... when they are not culled.
Some few chickens might be asymptomatic carriers of H5N1.

If the above is true, then the H5N1 that we are discussing is not, by definition, highly pathogenic. If the domestic fowl are not culled after a high path outbreak, then it is only a matter of time before all will be infected. Once infected, they are not likely to survive much more than a day. Any domestic fowl in a flock that survive an outbreak, would have somehow escaped infection of the virus, and therefore, would not be carriers.

 

[HenryN]

Re: Study: Migratory birds not to blame for spread of avian flu

some few chickens might survive ... when they are not culled.
Some few chickens might be asymptomatic carriers of H5N1.

Some asymptomatic ducks might have detectable H5N1 in throat swabs
or fecal swabs , some other maybe only (temporarily) have H5N1 in
other organs. And it might later become symptomatic or
swab-detectable triggered by unknown circumstances.

Please, most H5N1 in Europe is in countries which claim NO poultry infections, yet all DEAD wild bird isoaltes are Qinghai with independent introductions.

This paper claiming trade is more of the snow job to abck up "no H5N1" in western Europe until February 2006 (when it was then EVERYEHERE, with over 700 isolates and MULTIPLE independent introductions SIMULTANEOUSLY).

The trade nonsense just provides western Europe cover for the claim of no H5N1 in the fall of 2005 or the fall of 2006.

 

[HenryN]

Re: Study: Migratory birds not to blame for spread of avian flu

If the above is true, then the H5N1 that we are discussing is not, by definition, highly pathogenic. If the domestic fowl are not culled after a high path outbreak, then it is only a matter of time before all will be infected. Once infected, they are not likely to survive much more than a day. Any domestic fowl in a flock that survive an outbreak, would have somehow escaped infection of the virus, and therefore, would not be carriers.

Qinghai kills experimental chickens within 24 hours. It actually is highly highly pathogenic avian influenza as far as chickens are concerned.

I would think the hand wavers would have tired arms by now.

 

[scottmcpherson]

Re: Study: Migratory birds not to blame for spread of avian flu

Perhaps transport or smuggling can account for what I will call "border infections," for example between China and Vietnam.

But it cannot account for the sudden appearance of an identifiable substrain simultaneously in three places, on three continents. I am unaware of anyone trucking poultry from Qinghai to Nigeria.

So the correct answer to the theory may be "D", all of the above, but the the most correct answer must be migratory wildfowl.

We should be desperately seeking a new way to test this wildfowl in order to gain more positive results. For if we are getting thousands of negative tests, yet H5N1 appears with regularity along these routes, then we are missing either a test or a trigger.