The Spanish Flu of 1918 was Caused by an ________

Question

The Spanish flu of 1918 was caused by an ________ influenza virus.
A) H2N1
B) H5N1
C) H1N1
D) H2N2

Accepted Answer

The Spanish flu of 1918 was caused by the H1N1 influenza virus. This virus strain is different from the H2N1 and H2N2 strains that later caused other flu outbreaks. The H5N1 strain is also different and was responsible for the bird flu.