After an absence of more than one year, the H5N1 variant of the highly pathogenic avian influenza (HPAI) virus has been detected on a farm in Nepal, and new outbreaks of the disease have occurred in poultry in Taiwan and South Africa.
Two weeks after a nearby domestic duck flock died of unknown causes, suspicious symptoms were observed in a flock of 1,500 laying hens at a farm in the Chitwan district of Narayani zone, according to the official report from the Nepal Ministry of Livestock Development to the World Organisation for Animal Health (OIE). The 72-week-old birds initially showed a drop in egg production and reduced feed consumption, followed by the development of cyanotic combs, swollen heads, and mucus discharge from the nostrils. Within two weeks, all the hens had died.
The presence of the H5N1 HPAI virus subtype was confirmed at the farm, and all poultry within a three-kilometer radius were scheduled to be slaughtered in order to halt the further spread of the disease, reported Kathmandu Post.
With around half of Nepal’s poultry sector located in Chitwan, local farmers initially protested against the slaughter of 4,500 poultry in the contamination zone, reports Himalayan Times. The dispute—linked to the fixing of the zone’s boundaries—was subsequently resolved. The government pays 75 percent of the value of any birds that are culled to control the spread of HPAI.
Elsewhere in Asia
Taiwan’s agriculture ministry has confirmed a further outbreak of HPAI linked to the H5N2 virus variant to the OIE. Latest to be affected was a flock of 2,369 meat geese in Sihu town, which is in Yunlin county. Almost 100 of the birds died, and the rest have been destroyed. The farm has been cleaned and disinfected, and poultry units within three kilometers of the outbreak farm will be subjected to enhanced surveillance for the next three months.
More than 1,000 geese at a farm in Tainan have been culled after the same virus was detected there, according to Focus Taiwan in a more recent report. The Council of Agriculture has put the number of HPAI outbreaks in Taiwan so far this year at 71, with 530,148 birds culled.
After cleaning up from cases of H5N6 HPAI in captive birds at two locations in April, the Agriculture Department in Hong Kong has declared to the OIE that the disease situation has been resolved in the territory.
Africa: More outbreaks in South Africa’s wild, commercial birds
Twelve newly confirmed outbreaks of HPAI linked to the H5N8 virus variant have brought South Africa’s total over the last year to 188.
Latest official reports to the OIE confirm one outbreak in commercial ostriches—with 29 out of 3,730 birds testing positive for the virus in Western Cape—and cases in wild birds at 11 locations. These included more than 5,900 swift terns found dead at two sites in Western Cape Province.
Europe: HPAI virus detected in more Danish wild birds
A total of 23 wild birds found dead at 19 locations in eastern Denmark have tested positive for the H5N6 subtype of the HPAI virus, which was first detected in the country in March of this year. Among the affected birds were 11 buzzards and five eagles.
