<human>:  How many people died from the 1918 Spanish Flu Infection?
<bot>: The 1918 Spanish Flu was a pandemic that killed between 50 and 100 million people worldwide. It is estimated that it killed between 20 and 50 million people in the United States. The 1918 flu pandemic was caused by a strain of influenza virus that had not been seen in humans before. It was a particularly virulent strain of the H1N1 subtype, which is a type of influenza virus that is still common today.