Tuberculosis was the scourge of humanity until an antibiotic cure was discovered during the 1940's at Rutgers University.
But there were other milestones.
In 1903 the Nobel Prize in Medicine was awarded to Niels Finsen for discovering that untraviolet light could kill mtb bacteria.
A major development in hospitals was the invention on linoleum, which provided a smooth surface that could be washed and disinfected.
Then there was the introduction of hospital whites. Nurses and physicians wore white cotton clothing because it could be decontaminated against tuberculosis. Colored clothing cannot (or at least by normal washing). By addition of bleach the nurse or physician could insure they were not spreading the disease.
Newspapers that went into tb wards never came out. This was an inviolate rule.
During the 1940's every New York City subway car was equipped with a germicidal ultraviolet light fixture. Sadly this modification was discontinued during the 1950's.
But the most interest aspect of infection control in the transit system was due to the engineer William Gibbs McAdoo, responsible for the engineering of the Hudson and Manhatten Tubes (now known as PATH).
In Manhatten, the IRT used what is called "cut and cover" construction. They scooped out a channel and put a roof over it, which became the street.
McAdoo, however, had an interest in medicine, and was very concerned about tuberculosis, and the danger to commuters.
The line uptown for the H & M cars, built in 1904, was bored out with tight clearances for the cars. Each line had a separate tunnel.
His theory was that every arriving train would act as a "piston" and force air exchanges through the stations, and thus prevent tuberculosis.