Influenza: from bird to human

Abstract

Avian influenza (AI) is a highly contagious disease caused by influenza A viruses that affect wild and domestic birds. Although less frequent, avian influenza viruses can also be found in some mammalian hosts, including humans [1]. The natural reservoir of AI viruses is wild migratory birds belonging to the Anseriformes and Charadriiformes orders. As such, they play an essential role in the virus' evolution, maintenance, and spread [2]. Among birds, AI viruses spread via direct contact with infected birds’ secretions or indirectly from contaminated feed and water. Infected wild migratory birds can also spread AI viruses, along their migratory pathways, from one country to another and to domestic poultry in neighbouring areas [3].