Emergence of Human Avian-Influenza

Emerging viral diseases have become major public health problem in the World. Human-avian influenza is one of emerging viral diseases that significantly contribute to the global burden of respiratory diseases. The objective of this review was to discuss the most recent human-avian influenza outbreak documented in 2021. On basis of their epidemiological features, influenza in humans can be classified as seasonal influenza, pandemic influenza and human-avian influenza. Influenza in humans that are caused by avian influenza viruses which are transmitted across species to humans is known as human-avian influenza. So far, three avian influenza viruses have been recognized to cause human-avian influenza, namely, Asian H7N9 viruses, H5N1 viruses and H5N8. The most recent human-avian influenza outbreak was caused by H5N8, which was documented on February 2021 in Russia. The outbreak was associated with contact with H5N8 infected domestic birds. As the influenza viruses constantly evolve, there is possibility of global outbreak of the disease. Thus, it is necessary to take preparedness actions to counter pandemic threats as they are identified.