Reporting new cases of highly pathogenic avian influenza (HPAI) in commercial poultry flocks so far this year have been five Asian countries.
In the first week of the year, officials in Israel said that the disease situation in the north of the country was past its peak. Times of Israel reported a statement from the agriculture ministry that the previous few days had seen progress in the recovery. Fears that the H5N1 virus could be transmitted to humans from birds did not come about.
Despite this positive assessment, Israel’s veterinary authority reported eight further HPAI outbreaks in poultry. In each case, tests were positive for the H5N1 virus serotype.
According to the official notification to the World Organisation for Animal Health (OIE), latest cases bring the nation’s total outbreaks in domestic birds to 18. With the first outbreak detected three months ago, the number of poultry directly impacted has passed 1.07 million. This includes all mortalities and culls at infected premises.
Covering disease outbreaks starting between December 29 and January 9, the latest report outlines eight outbreaks, all on farms. Five premises were located in Hazafon (Northern District), two in Haifa, and one in Golan. In this current disease wave, previous cases have been detected in each of these districts.
Affected were three flocks of laying hens and of turkeys, as well as two of breeder chickens. Each flock comprised between around 6,300 and 107,000 poultry.
Further HPAI cases in Japan
In November of 2021, the first cases of HPAI linked to the H5N1 virus variant was confirmed in Japan.
So far this winter, the number of outbreaks in Japan caused by this serotype registered with the OIE stands at 10. Of the 675,000 birds directly impacted at infected sites, 472 have died. Other birds in each flock have been culled to prevent further spread of the infection.
The latest to be officially confirmed to the OIE were three outbreaks, all of laying hens at farms in the Saijo city area of Ehime. This prefecture is in the Shikoku region, which is one of the main islands to the south of Honshu. With a total of around 361,000 hens, each of the affected flocks comprised between 83,000 and 148,000 birds. The first signs of infection were observed between December 29 and January 4.
The latest update from the agriculture ministry indicates there have been two further related outbreaks in Kagoshima. These involved around 11,000 poultry in total. This prefecture belongs to the most southwesterly region of the country, Kyushu.
Earlier this winter, two Japanese poultry flocks tested positive for the H5N8 HPAI virus variant. No further cases have been detected since November of last year.
South Korea’s seasonal outbreak total passes 20
Since the start of this year, seven further HPAI outbreaks have been officially confirmed in South Korean poultry. Directly impacted were around 175,000 birds.
At each location, presence of the H5N1 virus serotype was confirmed between December 15 and January 6. Three outbreaks were in South Jeolla province, two in North Jeolla, and one in Sejong city. At three of these locations, outbreaks were identified through surveillance, before symptoms or increased mortality were observed.
In recent days, Yonhap has reported a further outbreak. Affecting a duck flock of around 33,000 birds in South Jeolla, this brings the country’s total outbreaks so far this winter to 21. It brings to more than 1.84 million the number of poultry affected by HPAI in South Korea over the past two months.
According to a separate OIE report, the H5N1 virus was detected in the droppings of wild birds at three location during December. Among these was a first positive test in Busan. This is a city region in the southeast of the country.
Vietnam battles two HPAI virus variants
Following a four-month hiatus, the H5N1 HPAI virus was detected again in Vietnam in mid-October of 2021.
Of the five outbreaks reported recently to the OIE, four were erroneously linked to another virus serotype, according to the latest official report from the national animal health agency.
Between October and December 28, HPAI affected a total of more than 18,000 poultry in village flocks. Each comprised between 35 and 12,000 birds. Widely dispersed, affected flocks were all located in different provinces in the South East, North Central Coast, and Red River Delta regions.
Also widespread across the country were the latest 18 HPAI outbreaks involving the H5N8 virus. They brought to 31 the country’s outbreak total linked to this serotype since June of 2021, and the number of poultry affected to more than 58,000. All belonged to village flocks.
Starting between September 26 and December 22, the outbreaks occurred in the same regions as those linked to H5N1, as well as South Central Coast and North East.
To the OIE, the Vietnamese authorities have recently declared the HPAI situation linked to the H5N6 virus serotype has ended. During the year to August of 2021, 60 outbreaks in village flocks were reported to the OIE. These involved around 126,000 poultry in total.
Five new outbreaks in Taiwanese poultry
In Taiwan, HPAI outbreaks in recent times have involved two different virus serotypes from other Asian states.
In September of 2019, the authorities registered the first cases linked to the H5N5 virus. Outbreaks have occurred sporadically since then.
The latest to be registered with the OIE was at a farm in Yunlin county in mid-December. The latest cases since September of 2021, these brought the outbreak total to 74, and the number of poultry involved to more than 597,000.
Meanwhile, the latest disease wave in Taiwan related to the H5N2 HPAI virus added a further four outbreaks during the last week of December. Affected were two commercial flocks in Changhua county (one of broiler breeders and one of native chickens), and a layer flock in Yunlin. Also testing positive for the virus was a small flock of native chickens.
Since this outbreak series commenced in mid-November of 2021, this outbreak series has involved around 181,000 poultry at 13 locations.
No further outbreaks in poultry in Iran, Pakistan
The latest notification received by the OIE indicates there have been no new cases of H5N5 HPAI in Iranian poultry flocks. Between October and mid-December, six outbreaks were reported in the country. These involved one farm and five village flocks.
Earlier this month, Pakistan’s veterinary authority declared the H5 HPAI situation in poultry “resolved.”
According to OIE reports, four outbreaks linked to this virus family were confirmed in the North West Frontier Province during the month of November last year. These affected a total of 6,700 poultry on two farms and two backyards.
China records new human infections with flu of avian origin
Over the period January 1-13, the World Health Organization (WHO) was informed about nine new cases of avian influenza A in human patients. All were in China, and were exposed to poultry before the onset of the illness.
Of the five latest patients infected with avian influenza A(H5N6) virus, two have died. The other three were described as being in a “critical” or “serious” condition with severe pneumonia.
They bring to 63 the number of lab-confirmed cases with this virus reported to the WHO in the Western Pacific Region since 2014. Of these, 29 patients have died.
The other four cases reported to the WHO involved the avian influenza A(H9N2) virus. Cases were aged between three and 14 years, all had mild disease, and have recovered.
Since December of 2015, 24 cases of avian influenza A linked to this virus have been reported in China, according to the WHO.
View our continuing coverage of the global avian influenza situation.
