Pandemic flu is virulent human flu that causes a global outbreak, or pandemic, of serious illness. Because there is little natural immunity, the disease can spread easily from person to person. The World Health Organization lists ten concerns if avian influenza becomes a pandemic.
Avian (or bird) flu is caused by influenza viruses that occur naturally among wild birds. The H5N1 variant is deadly to domestic fowl and can be transmitted from birds to humans. There is no human immunity and no vaccine is available. For more information, consult the Avian Flu Fact Sheet from the Center for Disease Control.
Resources help prepare for a pandemic flu outbreak: