25 AUG--This Day in US Military History

1901 – Clara Maass (25), army nurse, sacrificed her life to prove that the mosquito carries yellow fever.

Clara Louise Maass lost her life during scientific studies to determine the cause of yellow fever. A graduate of Newark German Hospital Training School for Nurses, she worked as an Army nurse in Florida, Cuba, and the Philippines during the Spanish-American War. In 1900, Maass returned to Cuba at the request of Maj. William Gorgas, chief sanitation officer. There she became embroiled in a controversy over the cause of yellow fever. To determine whether the tropical fever was caused by city filth or the bite of a mosquito, seven volunteers, including Maass, were bitten by the mosquitoes. Two men died, but she survived. Several months later she again volunteered to be bitten, this time suffering severe pain and fever. Maass died of yellow fever at the age of 25.
In her memory, Newark German Hospital was renamed Clara Maass Memorial Hospital and in 1952, Cuba issued a national postage stamp in her name. In 1976, the U.S. Postal Service honored Clara Louise Maass with a commemorative stamp.

https://thisdayinusmilhist.wordpress.com/2005/08/25/august-25/