The National Reference Laboratory for Fowl Plague at the FLI has detected high pathogenic avian influenza virus (HPAIV) of the subtype H5N5 in samples of a wild bird (barnacle goose) and in a turkey holding in Schleswig-Holstein. It is likely that the causative agent is a reassorted influenza virus based on the original H5N8. Mixed viruses, so-called reassortants, of influenza viruses are generated if several virus subtypes are present simultaneously in one infected animal and exchange genetic material during replication.
Such events are common due to the nature of avian influenza viruses, also of the subtype H5N8. Thus, the reassortants H5N1 and H5N2 were generated during the 2015 epidemics in the USA.
Also in the Netherlands, Montenegro, Italy, and Croatia cases of HPAIV H5N5 were detected in wild birds.
So far, no human cases of HPAIV H5N5 infection have been detected worldwide.
The occurrence of reassorted avian influenza viruses of the type H5N5 is not surprising and neither changes the risk assessment of the FLI on fowl plague nor the recommendations on the measures to be implemented.
