New York (City). Board of health.

A devastating disease, poliomyelitis attacks the motor nerve cells in the spinal cord, often leading to permanent paralysis or, in the most severe cases, death. The pathogen causing polio was identified by Karl Landsteiner in 1908 as a filterable virus, but the carrier of the virus and mode of transmission remained topics for heated debate for many years. Although it was known to strike the wealthy as well as the poor, in the popular imagination, the disease was indelibly associated with filth, vermin, and the poor.

The poliomyelitis epidemic that struck in the summer of 1916 was one of the largest ever in the United States, with over 27,000 cases reported from 26 states -- 8,900 in New York City alone -- and a mortality rate approaching 25%. In response, the emerging class of health professionals in New York intervened with a broad epidemiological and public health campaign using both the legal recourse available to them by virtue of new public health legislation and the old nostrum of moral suasion to convince the vulnerable into cleanliness and salubrious habits.

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