Influenza virus probably originated in birds, and moved to people thousands of years ago when people began to domesticate fowl. Influenza, in other words, was an “emerging disease”, much like SARS today. Over the centuries, influenza epidemics have had dramatic effects on human populations. For example, the 1918 pandemic, is estimated to have caused some 50 to 100 million deaths, and influenza (and smallpox) devastated the first nations peoples of North America with the arrival of Europeans.