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Food for Thought? A Quick Update on
H5N8 Poultry Flu from the Republic of
Korea
Nial Moores Conservation
Dr. Nial Moores, Birds Korea, December 4th 2014
Highly Pathogenic A (H5N8) was first detected in poultry in the Republic of Korea (ROK) in
early 2014 (Task Force 2014). This novel strain of H5N8 poultry flu is one that most likely
evolved within ducks in a duck farm, here in the ROK (Ku et al. 2014).
The outbreaks of this novel strain of H5N8 started on farms in the agricultural heartland of the
Jeolla Provinces in the southwest of the country (like H5N1 some years before), then spread
throughout much of the country. This spread was likely assisted by an initial movement of
173,000 ducklings from the outbreak farm to 24 farms in four provinces during the disease
incubation period. The initial outbreaks also affected wild birds – with up to 100 waterbirds,
many of them Baikal Teal Anas formosa, found dead at nearby Dongrim agricultural reservoir
(GAIN 2014).
Scientific Task Force on
Avian Influenza and Wild Birds
statement on:
H5N8 Highly Pathogenic Avian
Influenza (HPAI) in poultry
and wild birds
December 3rd 2014
As in previous years, these outbreaks were quickly followed by assertions that wild birds
(most likely Baikal Teal) were somehow infecting poultry, even though this would require
them to penetrate bio-secure farms in each outbreak area, infect poultry and then escape, all
undetected. Anyone who has seen even a small bird trapped in a building can imagine the
ridiculousness of this Mission Impossible-type scenario, undertaken by flocks of ducks and
geese. Nonetheless, there was little, if any, discussion in mainstream media about the level of
biosecurity at poultry farms and factories, and no discussion about the possibility of poultry
farms infecting local wetlands and waterbirds with virus, through e.g. poultry manure and
wastewater run-off.
As in previous years too, culls of poultry were carried out and roadblocks with disinfectant
sprays were employed in many parts of the country. A new measure in 2014 was the
industrial-scale spraying with disinfectant of wetlands and waterbirds at a number of sites
nationwide. This practice apparently continued for several weeks, even though it was contrary
to advice earlier provided by leading experts who argued that disturbing waterbirds in and
near outbreak areas simply increases the risk of spreading the virus to new areas.
Outbreaks in poultry in the ROK continued on into April. The Poultry Site (2014a) states that:
“The veterinary authority sent Follow Up Report No. 5 dated 30 April to the World
Organisation for Animal Health (OIE). The report described three new outbreaks of HPAI in
poultry between 6 March and 21 April 2014. The first started on 6 March in breeding
chickens in the region of Gyeonggi-do, the second in Sejong (also in breeding chickens) and
the third outbreak started on 21 April on a farm with domestic geese in Chungcheongbuk-do.”
Outbreaks at farms were then reported again in June. Again, The Korea Times reported that
“Studies are underway to keep track of infection routes, as many believe migratory birds are
to blame” (Kim 2014). This is even though the same report stated that it was known that
poultry at the outbreak farm had been brought from another outbreak area shortly before; and
even though this outbreak was several months after Baikal Teal and most other wild
migratory waterbirds had left the country.
We then need to fast-forward only a few months to the next outbreak in the ROK, this time in
September, again at a poultry farm, and again in the southwest of the country. Happily, no
subsequent outbreaks have been reported yet, and there appears to be no published evidence
of the virus in wild birds. The Poultry Site (2014b) simply reported that, in response to the
outbreak: “The following control measures are in place: control of wildlife reservoirs;
stamping out; quarantine; movement control inside the country; zoning and disinfection of
infected premises/establishment(s).”
It is the expression “control of wildlife reservoirs” that is of most concern here. This is
because it comes when a disease specialist is now recommending that: “in areas where
infection is documented, wild birds and infected poultry, especially domestic ducks, should be
culled” (Kang et al. 2015).
Unsurprisingly, this extraordinary recommendation has already been strongly criticized, prepublication, in a statement by the international Scientific Task Force on Avian Influenza and
Wild Birds released on December 3rd.
The Task Force, co-convened by the United Nations Environment Programme / Convention
on Migratory Species (UNEP/ CMS) and the Food and Agriculture Organization (FAO),
“urges agencies and organisations to…ensure there is no consideration of killing wild birds or
negatively affecting wetland habitats as disease control measures” (Task Force 2014). The
statement further challenges the recommendation in Kang et al. (2015) stating unambiguously
that, “killing wild birds should not be considered as a control measure as this is diversionary,
impractical, inefficient and contrary to the advice of all the major animal health agencies.
Similarly, negatively affecting wild bird habitat, by e.g. applying disinfectants to the natural
environment including wetlands, is not advisable as this is ineffective against the virus and
can harm the environment, wildlife and fisheries. Such measures are also contrary to
conservation commitments accepted by Contracting Parties to both the Convention on
Migratory Species and the Ramsar Convention on wetlands.”
The ROK hosted the Ramsar Convention conference in 2008 and the Convention on
Biological Diversity conference of the parties this year. Even though it is not a contracting
party to CMS, the ROK’s national commitment to these other conservation conventions
should be clear. And yet Dr. Kang and her colleagues work at what appears to be a
government agency, the Animal and Plant Quarantine Agency. Is this an appropriate
recommendation for a government researcher to publish? And is this recommendation
supported by her agency and by other government bodies?
It seems worthwhile to pause for a moment too, and to look at neighboring Japan to see how it
responds to Poultry Flu. Japan shares the same waterbird species with the ROK, and
populations of many of the same bird species are known to migrate through Korea to Japan.
Coincidentally, Japan also hosted the Ramsar Convention (back in 1993) and the Convention
on Biological Diversity conferences (in 2010). Japan has also experienced H5N8 outbreaks.
And Japan has been able (up to now at least) to control these outbreaks at more or less single
locations and sites, without spraying wetlands or calling for culls of wild birds. This is even
while here in the ROK farmers, poultry and wild birds seem to suffer repeated multi-farm
outbreaks, one after the other.
Why?
It seems likely that some migratory wild birds, once infected, can carry some strains of
Poultry Flu long distances. There are also multiple examples of wild birds likely infecting
other wild birds. Although we are still unaware of evidence of wild birds infecting poultry in
poultry-factories, it is quite possible that wild birds infected with H5N8 from the ROK have,
directly or indirectly, helped carry the virus to Japan. It is essential to remember though, that
such migrant birds do not recognize or respond to national boundaries. Their behavior and
susceptibility to disease, and the virulence of the viruses that they carry, does not change
suddenly once they cross from one country to another. And if one country (Japan) can control
outbreaks efficiently and another (the ROK) instead suffers from repeated outbreaks then
clearly the main problem is not with the wild birds. Instead, the problem has much more to do
with the response to outbreaks and the existence of infected links in the long chain of
industrialised poultry production and transport.
We urgently need to tackle the real source of the problem – industry practice – here in the
ROK. And this is only made more difficult when people, including scientists and agencies,
blame wild birds, spray wetlands with disinfectant or recommend culling wild birds.
Not only in the ROK, but globally, the pressure to continue trading and transporting poultry,
perhaps even before problems in this supply chain have been fully solved, seems huge. Only
this week “The International Poultry Council (IPC) called on its members to work with their
respective governments to ensure that ongoing influenza-related trade bans do not disrupt the
distribution of vital poultry breeding stock” (Poultry Site, 2014c).
Now, a few wild birds carrying H5N8 have reached Europe. And still, as before, the only
“birds” moving regularly (and legally) in large numbers directly from East Asia into the EU
are in the form of “treated egg products and eggs for processing…from South Korea and
China” (ECDC 2014). As suggested by the title: this really should be food for thought.
References and links
1. Task Force. 2014. Scientific Task Force on Avian Influenza and Wild Birds
Statement on: H5N8 Highly Pathogenic Avian Influenza (HPAI) in poultry and
wild birds. December 3rd 2014.
2. Ku B-K., Park E-H., Yum J., Kim J-A.,Oh S-K. & Seo S-H. 2014. Highly
Pathogenic Avian Influenza A (H5N8) Virus from Waterfowl, South Korea, 2014.
Open Letter. Emerging Infectious Diseases Vol 20. Number 9. September 2014.
Accessed on December 4th at:
http://wwwnc.cdc.gov/eid/article/20/9/14-0390_article
3. GAIN. 2014. Global Agricultural Information Network Report Number: KS1403.
January 21st 2014. Accessed on December 4th at:
Gain Reports/KS1403 Korea Confirms Detection of Highly Pathogenic Avian
Influenza _Seoul_Korea – Republic of_1-21-2014.pdf
4. Poultry Site. 2014 a. Three New Outbreaks of High-Path Avian Flu in South
Korea. Accessed on December 4th 2014 at:
http://www.thepoultrysite.com/poultrynews/32135/three-new-outbreaks-ofhighpath-avian-flu-in-south-korea
5. Kim S-J. 2014. New bird flu case in Daegu fuels concerns for nationwide spread.
Korea Times. June 18th 2014. Accessed on December 4th 2014 at:
http://www.koreatimes.co.kr/www/news/nation/2014/06/116_159387.html
6. Poultry Site. 2014b. Ducks Died from Highly Pathogenic Avian Influenza in
South Korea. Poultry News, September 26th 2014. Accessed on December 4th 2014
at:
http://www.thepoultrysite.com/poultrynews/33296/ducks-died-from-highlypathogenic-avian-influenza-in-south-korea
7. Kang H.M., Lee E.K., Song B.M., Jeong J., Choi J.G., et al. 2014. Novel
reassortant influenza A(H5N8) viruses among domestic and wild ducks, South
Korea. Emerging Infectious Diseases, ahead of print, February 2015
Accessed on December 4th 2014 at:
http://dx.doi.org/10.3201/eid2102.141268
http://wwwnc.cdc.gov/eid/article/21/2/14-1268_article
8. Poultry Site. 2014c. Poultry Industry Urges Exemption for Breeders from Bird
Flu Bans. Accessed on December 4th 2104 at:
http://www.thepoultrysite.com/poultrynews/33809/poultry-industry-urgesexemption-for-breeders-from-flu-bans
9. ECDC. 2014. European Centre for Disease Prevention and Control. Outbreak of
highly pathogenic avian influenza A (H5N8) in Germany – 13 November 2014.
Stockholm: ECDC: 2014.
Usop swamp, December 4