Evolution of highly pathogenic avian influenza virus infection in romania between 2016 and 2022

In recent years, more than 2,500 strains of highly pathogenic avian influenza (HPAI) have been detected in the European Union and the United Kingdom, in domestic poultry, wild birds, and captive birds. Most outbreaks have been declared in France, where two clusters have been identified until October 2021, followed by Italy, Hungary, and Poland. Losses in these countries have been huge, with more than 17.5 million birds culled and their carcasses destroyed. Most of the virus strains detected in wild birds were isolated in western and some northern European countries. These strains belong to influenza virus type A and subtype H5, indicating an increased risk of transmission to domestic poultry on commercial farms. The three outbreaks that have evolved so far in our country (2016-2017, 2021-2021, and 2022) have affected commercial farms all over the country, causing considerable losses. As in other countries, in Romania, non-compliance with biosecurity measures on farms and trade in birds from areas where avian influenza was evolving was the main causes and sources of infection. The information published on the ANSVSA website, presented in the form of press releases on the avian influenza situation in Romania, was used for this study. Data taken from Romania's reports to the OIE and data recorded in WAHID (World Animal Health Information Database) include information on the occurrence of new outbreaks of highly pathogenic avian influenza type A in the period 2016-2022. No outbreaks have been reported in Romania before 2016. The dynamics of new avian influenza outbreaks, the virus subtype identified, and the incidence of infections in domestic and wild birds were followed.