Avian Influenza Virus H5N1: A Review of Its History and Information Regarding Its Potential to Cause the Next Pandemic

Avian influenza virus H5N1, which has been limited to poultry, now has spread to migrating birds and has emerged in mammals and among the human population. It presents a distinct threat of a pandemic for which the World Health Organization and other organizations are making preparations. This article reviews information about the virus itself and its spread among poultry, migrating birds, mammals, and humans.