The virulence of avian influenza not only brought poultry farms across Europe under control but also wreaked havoc on wild bird populations and even infected mammals.Now, research published in the journal Nature confirms what many researchers already suspected: The epicenter of these viruses has spread from Asia to new regions, including parts of Africa and Europe.
Activity of highly pathogenic avian viruses H5N1 Since 2021, the epidemic has intensified globally, infecting and killing increasing numbers of wild birds and poultry, and posing risks to mammals, including humans. The H5N1 virus emerged in China in 1996. The scale of outbreaks of H5 viruses in wild birds has increased outside Asia since 2014, but the origins of recent viral resurgences and the underlying evolution of these viruses are unknown.
Vijaykrishna Dhanasekaran, a researcher at the University of Hong Kong, and colleagues used epidemiological data collected by the Food and Agriculture Organization of the United Nations and the World Health Organization to study the origins and changing trends of highly pathogenic H5 epidemics. Animal health from 2005 to 2022 and analysis of more than 10,000 complete viral genomes.
Key resurgence events were identified in 2016/2017, and genomic analysis revealed that the viral lineage originated in Asia (particularly China). on the contrary, Two new H5 viruses discovered between 2020 and 2022 Birds emerging from African and European bird populations indicate that shift Departing from the H5 epicenter, leaving Asia and heading to other continents. These strains were determined to have evolved through genetic reassortment of less pathogenic virus variants during transmission.
Authors believe avian influenza is persisting in humans longer and longer of wild birds are driving the evolution and spread of new strains.
The authors believe that these findings highlight the role of elimination strategies in limitingr virus spread Monitoring the prevalence of highly pathogenic avian influenza in bird populations worldwide and the importance of understanding virus evolution to mitigate and respond to new strains.