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the fact that HPAI virus can be transmitted from wild birds to humans directly or indirectly through contaminatedmaterials.

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"HPAI virus can be transmitted from wild birds to humans directly or indirectly through contaminated materials."

- any evidence for this.

...

.,..

thought not

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Thank you for your two emails dated 10 March 2008 and thanks again for your
concern on the control of avian influenza measures.

The H5N1 virus we isolated from wild birds in Hong Kong has so far proved
to be highly pathogenic avian influenza virus which can be lethal. As we
could not ignore the possibility that the virus could be transmitted from
wild birds to humans directly or indirectly through contaminated materials,
it would be necessary for the administration to introduce measures to
reduce such risk.

We are sorry for any inconvenience caused to you during the closure of Mai
Po Nature Reserve.

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Thank you for your email, in which you support my belief there is no scientific basis for closing Mai Po because a dead bird or two with H5N1 has been found nearby.

"we could not ignore the possibility that the virus could be transmitted from wild birds to humans directly or indirectly through contaminated materials"
- this is vague and woolly minded. Not remotely scientific.

As is clear from evidence worldwide, the H5N1 variant of concern is primarily a poultry disease. And whilst the administration has done much to reduce the incidence in local poultry, and associated markets (such as the bird market), we have not lately seen such draconian measures as closure taken recently.

As you should be aware, no wild bird species is known to be capable of surviving, sustaining and spreading H5N1 poultry flu.
It is highly lethal to wild birds, so an infected bird soon sickens, and dies, swiftly ending a potential chain of transmission.

Despite extensive testing, not one apparently healthy wild bird has tested positive for H5N1 poultry flu in Hong Kong.
The dead wild (and "wild" - for some individuals surely or probably from captivity) birds found in Hong Kong that tested positive for h5n1 have been from scattered locations. Despite the bird concentrations at Mai Po, and surveillance there, is it just one case from Mai Po over the years? - in turn, suggesting H5N1 is rare in wild birds, but overwhelmingly outside the reserve.
You might wish to consider just how and where these birds may have contracted the virus - scavenging dead, dumped poultry (smuggled in, so with chance of h5n1), or infected songbirds from captivity?

Especially with birdwatching not involving contact with wild birds, and no case worldwide (that I'm aware of) of a person thought to have contracted h5n1 from a wild bird, there is and was no discernible risk to Mai Po visitors.

Thus, knee-jerk reaction would indeed seem an appropriate description for the Mai Po closures.

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Thank you for your email.

Overseas  studies  have  shown  that  migratory  water  birds are a natural
reservoir  of the highly pathogenic H5 avian influenza (HPAI) virus.  These
birds  may  spread the virus to other birds when congregating.  Every year,
over  100  000 migratory birds visit Hong Kong and Mai Po Nature Reserve is
the  major  congregation place for these birds, especially water birds.  It
is for this reason that the Reserve attracts many visitors.

The  potential transmission of HPAI viruses from other regions to Hong Kong
via  migratory  wild  birds has long been of concern to the public.  In the
area  of  Mai  Po Nature Reserve, faecal droppings or cloacal swabs of live
wild  birds  were  regularly  collected  and  tested  by  the  Agriculture,
Fisheries  and  Conservation  Department  (AFCD) and the University of Hong
Kong.  In 2007, over 8,700 dead birds had been tested for HPAI.  There were
21  dead  wild  birds,  including 3 water birds, tested positive for highly
pathogenic H5N1 viruses.

We  hope  you  would understand that in view of the risks posed by the HPAI
virus,  the  Government  has  to  take  appropriate measures to prevent the
possible spread of the disease in Hong Kong and to protect public health.

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Thank you for your latest email.
This only reinforces my belief that science is not behind the closures of Mai Po in supposed attempts to reduce threats from bird flu. Instead, we have something more akin to arm waving (as one of my physical chemistry lecturers put it), with leaping to conclusions; almost a superstitious belief - as if the Tooth Fairy Bird I've written of is alive and well, and living in the brains of the Food and Healthy Bureau.
Sadly, these anonymous "experts" in the Dept of Health would seem not too strong on science, and lacking understanding of the natural world, including wild birds, and evolution. It would do them good to get out more, and do a bit of thinking.

"Overseas studies have shown that migratory water birds are a natural reservoir of the highly pathogenic H5 avian influenza (HPAI) virus. "

- you need hardly say more really.
Overseas studies - yet we talk of Mai Po, where there have been significant studies of avian flu in wild birds.
Also, "natural reservoir of H5" - when it is h5n1 of forms ("genotype Z" etc) from poultry farms that are important.

Suppose I were to suggest that movements of people should be controlled, as many are carriers of coronaviruses?
- ridiculous, right? - as the fact SARS is a coronavirus does not mean all coronaviruses are bad.
A great many people have the common cold, much as many wild birds have avian flus; including H5 (albeit H5 in wild birds can be low path, too, I believe)

Studies including, importantly, at Mai Po show that wild birds are not good reservoirs of H5N1 of the forms that are of concern - which might be better termed poultry flus, as they originated from poultry farms.

As mentioned ad infinitum, by myself, WWF, members of the HK BIrdwatching Society and so forth - assessments of the dead "wild birds" with H5N1 in recent years have shown that several were not of wild origin; also the dead birds tended to be found in and around urban areas; there seems a pretty good correlation with bird and even poultry markets.

Despite extensive testing of healthy wild birds at Mai Po, all wild birds - and "wild" birds - found to have H5N1 in Hong Kong have been dead, or sick and dying.
No apparently healthy wild bird has been found to have H5N1; no H5N1 case as yet at Mai Po.

I could re-iterate re evolution and infectious diseases.
However, the above - as my previous emails - should suffice to show that closing Mai Po was little more than a knee-jerk reaction; not a benefit to people's health.
[You want to stop remote health risks, go ahead and try: maybe keep people in lest meteorites smack into them when outdoors, or whatever.
Perhaps more absurd than closures: banning birdwatching tours in Kowloon Park, when the park itself was not closed. Nobody can come up with a shred of science behind this. Nobody.]
I'm sure you agree.

I hope the "experts" will take some measures to acquaint themselves with the natural world, including birds - I'm sure the Mai Po staff would be happy to take them around come late autumn, when waterbirds abound.

Fingers crossed!