Just had email from German birder, returned from birding trip inc South Korea [and HK]:
This situation is in strong contrast to what I learnd about Poultry Flu from you, the Asian ornithologists.
Therefore I wrote a letter and sent it to the relevant bodies in Germany. I enclose this letter, but because it is written in german I summarise it als follows: It is unlikely, that wild birds are vektors for the desease about longer distances. There is no correlation between migration routes and the spread of Poultry flu. Only one occasion with a likely transport via wild birds (from China to southern Mongolia) is dokumented, where the desease tapered off after a while. No poultry was affected. There are countries with many migrants from affected areas (Japan, South Korea, Malaysia) without Poultry flu outbreaks within the wild, but these countries do have stong import controls. Instead of this it is possible to explain the spread of Poultry flu with the trade of poultry and poultry products. The latter include chicken faeces (as fertilizer for fishery and agriculture purposes) and and chicken litter (as food for domestic stock, including chicken). The virus can survive under good conditions up to 30-35 days outside living birds. So far in Europe, swans are among the first victums of Poultry flu outbreaks in the wild. This might be explained by their feeding ecology (in fishponds as well as on fields). I condluded, that the tale of wild birds as vektors obviously prevents the authorities to search for the real causes of the actual outbreaks.
This letter has got some attention (as was intended). There was a lot of approval, but also some criticism. I am going to answer it, but maybe you can help me with some thoughts. I will search the internet for additional arguments, but you might have the answers right in your mind.
I’ve sent quick answers:
Glad you’ve sent the letter, and stirred a little debate.
Way too much panic in Europe I believe. Also terrible re cat owners dumping pets (I’ve read).
Quick attempts at answers:
– no, it is fanciful that it could happen “over some migration periods”. Poultry flu is invariably lethal to wild birds (may be some ducks – some individuals – that survive, but if present in wild birds, get deaths).
As well as connections via migrants, also trade connections, including smuggling.
– evidence for “most birds do not die” please? So far, evidence strong that most birds do die.
Meaning of the dying birds – mostly swans – in Europe is unclear. We don’t know if all the infected swans are dying, even after moving as result of cold weather (and not being fed by people?)
So far, I haven’t seen re even one apparently healthy wild bird being found to have H5N1 in Europe/west Asia. (And no wild bird at all, so far, that I know of in Africa.)
In Romania, case of infected swans on some ponds; observation and testing showed they didn’t infect other waterbirds sharing the ponds.
Here in Hong Kong, virus present and nearby for 10 years now. Mostly, for this time, not present in poultry or wild birds here. As yet, all cases in wild birds have been in dead birds. Over 16,000 apparently healthy wild birds tested so far; all negative.
– how to explain this, other than virus dying out as wild birds die.
Likewise, recently published research shows 4 distinct strains in southern China:
– controls have strengthened; yet virus hasn’t recurred.
Many migrant waterfowl to Japan and S Korea – as you’ve seen; yet – like Hong Kong – no evidence of H5N1 in them.
[HK this winter – none in waterfowl; some in a few songbirds, and crows: starting after around Chinese New Year, associated with H5N1 in at least one smuggled chicken.]
– if indeed readily carried by wild waterbirds, why no outbreaks in wild waterbirds east of Caspian Sea, right across to Japan, this past autumn and this winter? People are testing in several places; including India, where many Qinghai birds spend the winter.
– Malaysia had small recent outbreak, blamed on smuggled fighting cocks.
– Doesn’t have to be this way. Mixture of ways that avian flu spreads in poultry industry. Day old chicks, dirty crates etc. Spread thro Russia, along rail lines and roads, then to Turkey/eastern Europe.
– seems so; Vietnam thought they eradicated it, but returned.
Also in recent paper: a virus strain introduced to Vietnam was close to one from sw China, it was thought transport was likely cause.
A terrible situation.
The problems are within farming; it was poultry farming that created this form of H5N1 (and its various strains), and is chiefly responsible for spread.
I believe we will look back on this period, and find it shameful. And maybe wonder why people weren’t more stout-hearted, perhaps even standing back to look at the facts – including that it’s not easy to catch H5N1: one way in Vietnam was drinking raw duck blood.