On January 30, 2006, Dr. Michael J. Klag, dean of the Johns Hopkins Bloomberg School of Public Health, convened a day-long symposium to examine the public health aspects of a potential pandem c like H5N1 avian influenza. The event brought together experts on every facet of the avian flu, to educate the wider community on what we know and don't know about this alarming disease. In Part 3, Admiral John Agwunobi, Assistant Secretary for Health with the U.S. Department of Health and Human Services, gives an overview of avian flu.