Controlling the emergence of highly pathogenic avian influenza viruses: one of the challenges of the 21st century?

Millions of farmed birds culled, hundreds of gannets dead on the coast, dying marine mammals suffering from neurological disorders: these events regularly make the headlines. What do they have in common? Highly pathogenic avian influenza viruses (HPAIV). HPAIVs are viruses capable of replicating systemically, causing both asymptomatic infections and devastating mortality, depending on the susceptibility of the host species. Known for several decades now, these viruses have seen their circulation particularly increased in recent years, and have been responsible for massive epizootics on several continents. In addition to the devastating effects they can cause in poultry and wildlife, HPAIVs are also capable of crossing the species barrier. Improving knowledge about these viruses and better control of their spread therefore has several objectives: to protect public health, to guarantee food safety, to preserve biodiversity and the economy of the poultry industry. This article reviews the current state of knowledge on HPAIVs: from their epidemiology to the mechanisms of emergence and control measures.