Monday, November 16, 2020

Kagawa Japan Reports 5th Outbreak Of HPAI H5 In Poultry

Kagawa Prefecture - Credit Wikipedia

#15,563

For the third time in less than 2 weeks (see here & here) Japan's Ministry of Environment has announced the detection of HPAI H5 (likely H5N8) in a commercial poultry farm in Kagawa prefecture. HPAI H5 has also been detected in environmental samples from birds in both Hokkaido and Kagoshima Prefecture (Izumi City).

Japan - much like South Korea and Northern Europe and the UK - continue to deal with a resurgence in avian flu activity after 3 years of relative quiescence. 

The relatively short history of avian flu has been that after large outbreaks - sometimes lasting several years - we often see a multi-year decline before the next wave.  

While we are nowhere near the level of activity reported during the last big wave in the winter of 2016-2017 (see EID Journal: Comparison of 2016–17 and Previous Epizootics of HPAI H5 In Europe), this upward trend is still a concern. 

A link and excerpts from the latest (translated) report from Japan's MOE follows.  I'll have a bit more  when you return.

Confirmation of pseudo-patients with highly pathogenic avian influenza in Kagawa Prefecture (fifth case in domestic poultry)

On November 15, 2nd year of Reiwa, it was reported that a pseudo-patient with highly pathogenic avian influenza, which was the fifth case in domestic poultry, was confirmed at an egg-laying chicken farm in Mitoyo City, Kagawa Prefecture. In response to this report, we have designated a radius of 10 km around the outbreak farm as a priority area for wild bird monitoring, and are strengthening wild bird monitoring.

1. 1. Background

11 May 14 (Saturday)

・ Kagawa Prefecture received a report that the number of dead chickens increased, and the farm concerned (located within a radius of 3 km from the first, third, and fourth domestic farms that occurred in Kagawa Prefecture this year *) Conducted on-site inspection.・ On the same day, a simple influenza test was conducted on the chicken and the result was positive.
11 May 15 (Sunday)
・ As a result of genetic testing of the chicken, it was confirmed that it was a H5 subtype and was a pseudo-patient with highly pathogenic avian influenza.
Domestic first case of occurrence in poultry ( November 5) and domestic third example of occurrence ( 11 May 11 due to the days), for feeding chicken in Kagawa Prefecture is the poultry farm, carried out genetic tests and antibody tests If you do, confirm negative.
2. Correspondence
(1) On November 15, the area around the farm with a radius of 10km was designated as a priority area for wild bird monitoring, and wild bird monitoring is being strengthened.
(2) No abnormalities such as mass death of wild birds were confirmed in the emergency investigation accompanying the occurrence of the first to third cases of domestic poultry in Kagawa prefecture. In addition, Kagawa Prefecture has been conducting an emergency survey since November 14th for the fourth domestic outbreak of a house in Mitoyo City.
(3) According to the "Technical Manual for Response to Highly Pathogenic Avian Influenza in Wild Birds" ( published at http://www.env.go.jp/nature/dobutsu/bird_flu/manual/pref_0809.html ) We will take measures such as strengthening monitoring.
(4) The nationwide response level for wild bird surveillance has been raised to the highest level, "response level 3", as of November 5, and we will continue to strengthen monitoring of wild birds nationwide.
          (Continue . . . )


Although large scale avian flu outbreaks are most common in Eurasia, North America is far from immune.  During the winter of 2014-2015 Canada and the United States experienced an HPAI H5 avian epizootic that spread across 15 states and several Canadian provinces (see map below), which resulted in the loss of 50 million birds.

Although we've seen some limited outbreaks of HPAI & LPAI H7 in poultry (see EID Journal: Mammalian Pathogenesis & Transmission of Avian H7N9 Viruses - Tennessee 2017 and APHIS: Epidemiology Report On Indiana H7N8 Outbreak), North America has been spared any large avian epizootics for the past 5 years.

While the Pacific and Atlantic oceans provide a bit of a barrier, there is ample evidence of birds from both Asia and Europe intermingling with North America birds, allowing for the transoceanic spread of avian flu viruses (see EID Journal: Reassortment in Wild Birds in Alaska before H5 Clade 2.3.4.4 Outbreaks)

A 2014 study in PLoS One: North Atlantic Flyways Provide Opportunities For Spread Of Avian Influenza Viruses also warns that avian viruses in Europe may have similar opportunities to arrive via Iceland and Greenland.

For North Americans, our Arctic Refuge, where more than 200 bird species spend their summers, serves as a central hub, and funnels migratory birds south each fall via all four North American Flyways.

Credit U.S. Fish & Wildlife 

All of which means that while it is currently Europe and Asia who are raising their biosecurity in order to fend off another major epizootic, we in North America are far from immune.  The USDA has some advice on how to Defend The Flock at the website below.

For more on how avian flu strains from Asia, Europe, or even Latin America might arrive again in North America, you may wish to revisit:


Proc. Royal Society B: Influenza A Viruses Remain Viable For Months In Northern Wetlands - USGS
 
 
PLoS One: Rapid Evolution of Mexican H7N3 HPAI Viruses In Poultry