05.11.2016

The Hungarian authorities have confirmed HPAI H5N8 in a (wild) Mute Swan by a lake in Csongrad region, a well-known rest place for migratory birds at this time of year. This is the first report of HPAI H5N8 this year in the EU and follows the case in wild birds in Central Russia reported in June 2016. The same subgroup or clade (2.3.4.4) of H5 viruses was also detected in USA (Alaska) in August 2016 in wild mallards. In other unrelated disease reports, the Netherlands has confirmed an outbreak of low pathogenic avian influenza, H5 (N type not determined) in turkeys in Deurne, Limburg. The holding contained approximately 12,000 turkeys, 5,000 ducks and 2,000 pheasant; no clinical signs were observed. The birds have been depopulated. The four other premises in the 1km zone have been screened.
In an unlinked incident, the German authorities reported an outbreak of LPAI H7N3 in captive birds in Mannheim on 18th October. Disease was detected in pheasants and a further 52 birds (ducks, guinea fowl and peacocks) were humanely destroyed.
The finding in Hungary is significant because the virus was last detected in the EU in early 2015 (including two incidents of wild Mute Swans in Sweden collected in February/March 2016), indicating that it may not have returned with wild birds last winter. These reports, alongside that from Russia in June, indicate that this particular virus is circulating in wild birds which may transport it over wide distances through the migration routes. This particular subgroup or clade of H5 HPAI virus does not always show high mortality in wild birds and the presence in new regions may be detected first in clinically susceptible poultry species where there has been direct or indirect contact with infected wild birds. In June there was an outbreak of LPAI H7N9 avian influenza in poultry in Friesland in the northern Netherlands; this was the European strain of virus and not related to the virus circulating in poultry in China and causing human cases. The outbreak in Germany is restricted to a zoo and has not been detected in poultry.