The so-called Spanish Flu pandemic had its origins in the then-world's largest concentration of soldiers at Fort Riley, Kansas, not Spain. The disease vectors were the migrating bird flyway heading for a marshy sanctuary, as interfacing with swine production.
Healthy farm kids were hardest hit as their lung tissue was most welcoming. City kids with poor lung function were harder to infect. The sick who were housed in cold, drafty outdoor tent facilities (because hospitals were full) did better than those indoors because of enhanced oxygenation.
God have mercy on all those who die an unprovided death. My Great-uncle, Art, died from the Spanish Flu. May he rest in peace.