Two countries in Europe—Hungary and Romania—reported more highly pathogenic H5N8 outbreaks in wild birds and poultry, as South Korean researchers revealed new findings about the H5N6 strain, which hint that Mandarin ducks could be a host species that can spread the virus beyond its borders.
In an update today on H5N8, the United Nations Food and Agriculture Organization (FAO) said the virus with pandemic potential has now been confirmed in birds in four of the world's regions, including 40 countries.
Latest H5N8 outbreaks in Europe
Hungary's agriculture ministry today reported 47 more H5N8 detections in wild birds found dead from Jan 5 to Feb 15, affecting 11 bird species, though the largest portion were mute swans, according to a report to the World Organization for Animal Health (OIE).
The birds were found dead across a wide area of Hungary, encompassing 16 different counties. Five of the events involved dead birds in Budapest, Hungary's capital.
Details of the numerous H5N8 outbreaks come less than a week of a report on 19 outbreaks in Hungarian poultry covering roughly the same period.
Meanwhile, Romanian officials said in two new OIE reports that tests have linked H5N8 to five more outbreaks in wild birds and two more in backyard poultry.
The outbreaks in backyard poultry began on Feb 6 and Feb 20 at holdings in Arges County in the south-central region and Constanta County in the southeastern corner. The virus killed 50 of 57 birds at the two locations.
Meanwhile, officials said H5N8 was found in wild birds—swans and a mallard—found dead between Feb 15 and Feb 20 at five locations in three counties: Bucuresti, Constanta, and Galati.
Korean scientists profile H5N6 virus
In the H5N6 study, researchers from South Korea described genetic findings from an isolate collected from a Mandarin duck fecal sample at a wintering habitat for wild birds in October 2016. The team reported its findings yesterday in an early online edition of Emerging Infectious Diseases.
Starting in November, South Korea and Japan have reported several H5N6 outbreaks in wild birds. China, Hong Kong, Taiwan, Myanmar, and Vietnam have also reported recent H5N6 outbreaks.
Analysis of the South Korean H5N6 isolate showed that it was a reassortant clade 220.127.116.11 influenza A virus that is genetically similar to H5N6 viruses isolated from birds in China, Vietnam, Laos, and Hong Kong, as well as human isolates. Since 2014 H5N6 has sickened 17 people, all in China.
The team said Mandarin ducks are year-round resident in South Korea, with some migrating to Russia and eastern Asia. They added that Mandarin ducks were found to harbor H5N1 in 2010 and H5N8 in 2014 and 2016, suggesting that they could be a host species for the 18.104.22.168 H5 clade and could carry the virus throughout South Korea and into other countries.
Feb 28 OIE report on H5N8 in Hungary
Feb 28 OIE report on H5N8 in Romanian wild and backyard birds
Feb 27 OIE report on H5N8 in Romanian wild birds
Feb 28 FAO situation update on H5N8
Feb 27 Emerg Infect Dis report