Historically, it's believed the Spanish flu originated in *China*.
Returning troops, toward the end of World War One, brought it to the U.S.. Medically, all that could be determined at the time, was that all, or most,of the infected troops, had been through Spain. The only common denominator in 1917-1918.
It'd be nice, if libs would actually read a book, instead of taking history lessons from an Stephen Colbert.
RE: What do the songs lyrics mean?
The opening lines, mean the writerwas obviously constipated.