Cholera organized American public health from the city up to the federal government. Three waves killed about 150,000, including ex-President Polk in 1849. New York's 1866 health board cut deaths through sanitation, foreign science from John Snow and Robert Koch explained the disease, and the 1892 Hamburg death ships led to the 1893 National Quarantine Act, which gave the Marine Hospital Service real national authority.
Death tolls are estimates from an era of poor record keeping. Credit for the science is shared by Snow and Koch, and the 1892 to 1893 federal turn was entangled with anti-immigrant politics.