How did Carlos Finlay and Walter Reed help control yellow fever in Panama?

Carlos J. Finlay and Walter Reed were instrumental in controlling yellow fever, though their primary work took place in Cuba rather than Panama.

Finlay, a Cuban epidemiologist, first proposed in 1881 that yellow fever was transmitted by the Aedes aegypti mosquito. While his theory was initially ignored, it provided the essential foundation for later research.12

In 1900, the U.S. Army Yellow Fever Board, led by Reed, conducted rigorous experiments in Cuba that confirmed Finlay’s hypothesis. Reed proved that the disease was transmitted solely through the bite of infected mosquitoes and debunked the prevailing belief that it spread via contaminated clothing or bedding (fomites).12

These findings were subsequently applied by William Crawford Gorgas, who successfully eradicated yellow fever in Havana by controlling mosquito populations. Gorgas later replicated this sanitation strategy in Panama, which was critical to the successful construction of the Panama Canal by significantly reducing the death toll among the workforce.123