"Pinpointing the origin of the 1918 pandemic virus, including discovering exactly how, where, and when it emerged to initiate sustained human-to-human pandemic transmission, will likely never be possible. Because human-adapted influenza A viruses are only moderately contagious and moderately fatal, it is the nature of influenza pandemics that many weeks, and more likely many months, must pass between the emergence of a pandemic and its detection. During this time, there would be relatively few deaths, given (relatively) low influenza case fatality, and those deaths that occurred would be difficult or impossible to recognize beneath the background of deaths from seasonal influenza and from other prevalent respiratory agents. It remains important to seek genomes of additional influenza viruses from the months and years before May 1918, when the earliest virally confirmed fatal 1918 case occurred. The hope is that new viral sequences identified from before 1918 will help to answer fundamental questions about the origin of the 1918 pandemic virus and population immunity before the pandemic, but the viral evolutionary and host adaptational sequences of events that bridge wild waterfowl gene constellations and pandemic viral genomes occur inside a “black box” that currently remains largely invisible to science. We have information about the genome of the 1918 virus at a very early stage of its emergence, but we do not yet know anything about evolutionary steps that may have occurred before it became adapted to human hosts."