Occurrence and control of highly pathogenic avian influenza in European Union countries, including Poland in the 2020/2021 season

Highly pathogenic avian influenza is one of the most contagious and dangerous infectious animal diseases of the twenty first century. Its recurring outbreaks in recent years have been increasing in scope and have resulted in previously unrecorded losses in poultry production, related to both its high mortality rate and the need to kill poultry in outbreaks, as well as economic losses related to trade restrictions imposed on affected countries and regions. An increase in the average duration of the so-called ,,flu season" was also observed. This is related to the shift in the phenological calendar observed in nature, which was created based on the analysis of climatic factors, weather and the impact on animal behavior. Currently, in the countries of the European Union, the direct legal basis for the control of highly pathogenic avian influenza in the EU, is provided by the provisions of Regulation (EU) 2016/429 of the European Parliament and of the Council (EU) (Animal Health Law, AHL), while the detailed manner and mode of control of this disease is defined in the Commission Delegated Regulation (EU) 2020/687 of December 17, 2019.