Managing Avian Flu: A science roadmap and action plan

Large-scale outbreaks of highly pathogenic avian influenza are currently spreading across several countries, affecting many animal species beyond birds. The disease, commonly known as avian or bird flu, is caused by the H5N1virus, which has spread widely among wild birds around the globe since 2020-21, resulting in unprecedented mortality in wild birds and domestic poultry. The current virus strain, clade 2.3.4.4b, differs from the one circulating prior to 2020. It is increasingly spreading beyond wild birds to a wide variety of land and marine mammals, including more recently to dairy cattle in the US. In addition to its devastating effect on the welfare of birds and other animals, there are increasing socioeconomic concerns stemming from the impact of H5N1 on the agrifood sector with consequences on food security and pricing. The detection of the H5N1 virus in hundreds of bird species and over 200 mammals highlights its threat to biodiversity and species at risk.