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Bird Flu: Is a Pandemic Looming in Our Future?

Author(s): Deanne Erdmann, MS, Christopher Burnett, BA, and Nancy Moreno, PhD

Avian Influenza (Bird Flu): H5N1

H5N1 is a variant of influenza A virus that usually does not infect humans. Thus, most humans do not have pre-existing immunity to this strain. Beginning in 1997, more than 600 cases of human infection by bird influenza virus H5N1 have been documented. It is believed that most cases of H5N1 were spread by direct contact with infected poultry, and to date, the virus has not acquired a mechanism for efficient transfer from human to human.