The Panama Canal wasn't beaten by engineering first — it was beaten by mosquitoes

A French attempt to build the Panama Canal collapsed in the 1880s after tens of thousands of workers died, mostly from yellow fever and malaria, whose cause was unknown at the time. When the US took over, physician William Gorgas applied newly proven mosquito-transmission theory to fumigate camps and drain standing water. Disease deaths collapsed, and the canal opened in 1914.

— David McCullough, The Path Between the Seas: The Creation of the Panama Canal — 1977
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