As New Zealand reports its first ever outbreak of highly pathogenic avian influenza (HPAI), further cases have been confirmed on poultry farms across the region from Japan and South Korea to Turkey. In China, a number of people have been confirmed with recent virus infections of avian origin.
Last week, avian influenza virus was detected for the first time in New Zealand. The presence of the H7N6 HPAI virus serotype was detected in a flock of commercial laying hens in Otago on the South Island after a spike in mortality.
In an update on the situation, Biosecurity New Zealand has confirmed that birds in a second poultry house have also tested positive for the virus, according to the Ministry for Primary Industries.
To stop the further spread of the virus, a total of 80,000 birds in the two sheds will be culled over the next 2-3 days. Ministry veterinarians will remain on site to support the affected company, Mainland Poultry, and to check for signs of the virus spreading further. The farm is reported to be in a remote rural location. Strict biosecurity measures are in place there, restricting the movement of poultry, feed, and equipment on and off the property.
The risk to human health is described by the ministry as “low.”
Rising HPAI cases in East Asia
In mid-October, the first outbreaks of HPAI of the fall were confirmed on Japan’s poultry farms.
Responsible for the first cases was the H5N1 virus serotype, and this has now been linked to 12 outbreaks in the country so far.
Based on notifications to the World Organisation for Animal Health (WOAH), the first 10 farms to be affected by outbreaks had a total of more than 1.2 million birds up to mid-November.
Since then, the agriculture ministry has reported two further HPAI outbreaks, likely involving the same virus variant. Latest to be affected are a flock of around 2,500 meat ducks in the Greater Tokyo region, and 35,000 meat chickens on the most southwestern island of Kyushu.
Following a five-month hiatus, HPAI was confirmed again in South Korea at the end of October.
So far, the number of confirmed outbreaks linked to the same virus variant (H5N1) stands at five.
With the confirmation of two more outbreaks, the agriculture ministry has imposed a temporary nationwide standstill of poultry-related vehicle movements.
Latest to test positive for HPAI were a flock of 22,000 ducks in South Jeolla province, and 233,000 chickens in the Sejong city area.
At the end of November, Taiwan News reported a warning from the agriculture ministry to poultry owners. It called for vigilance over bird health after the H5N1 HPAI virus was detected in wild birds and a small number of chickens in the south of the territory.
Further outbreaks in Turkey
Also in the far west of Asia, the H5N1 HPAI virus is hitting poultry farms.
Total outbreaks affecting commercial farms in the Republic of Türkiye (Turkey) has reached five since the end of October, based on notifications to WOAH. So far, outbreaks have been confined to two western provinces — Konya and Afyon. The number of commercial birds directly impacted has already passed 10 million.
HPAI resolved in Australia, Bhutan
In May of this year, poultry farms in three Australian states were almost simultaneously hit by different serotypes of HPAI virus.
Control over the disease was effective, and the nation’s veterinary agency has declared to WOAH that two of the outbreak series have been “resolved.”
Declarations apply to the H7N9 virus variant, which was linked to a single outbreak in Victoria, and to the H7N8 serotype, which affected four commercial farms in New South Wales and the Australian Capital Territory.
Furthermore, the animal health authority in the Kingdom of Bhutan has also reported to WOAH an end of an earlier HPAI outbreak series.
The disease hit a small poultry flock in the south of this South Asian state in August. No further cases have been reported to WOAH since that time.
Further human infections in Asia
Over the past month, the World Health Organization (WHO) has been informed about seven more confirmed cases of infections with influenza virus of avian origin in the Western Pacific region.
All of the patients tested positive for the influenza A(H9N2) virus in the People’s Republic of China — in Hunan, Hubei, Jiangxi, and Sichuan. Dates for the onset of symptoms ranged from September 23 to October 14. While symptoms in three people were severe enough to require hospital treatment, all are reported to have recovered.
Since the region’s first infections with this virus variant in 2015, WHO has been informed of 111 cases, of which 108 were in China.
View our continuing coverage of the global avian influenza situation in poultry, and on disease developments in the U.S. dairy sector.
