efforts in the mid-1400s by the Republic of Ragusa to prevent the spread of bubonic plauge (McNeill, 1976). The republic, on the eastern shore of the Adriatic, required incoming ships to set anchor at sites away from the harbor. The ships' occupants were then required to spend 30 days ("trentina," later extended to 40 days, or "quarantina") in the open air and sunlight, a practice thought to preclude the spread of plague.
The earliest quarantine requirements in America were established in 1647 by the Massachusetts Bay Colony, specifically for ships arriving from Barbados. Other colonial settlements followed suit, with the goal of preventing the spread of yellow fever and smallpox (Williams, 1951). Quarantine proved to be an appropriate tool for controlling smallpox, an infectious viral disease spread easily from person to person, but the practice was ineffective in combating the spread of yellow fever, a mosquito-borne viral disease. In 1799, Congress granted authority for maritime quarantine to the secretary of the treasury and directed that state health laws (including quarantine of ships) be observed by customs officers.
In 1876, as a result of the failure of the Treasury Department to exercise its quarantine authority, U.S. Surgeon General John M. Woodworth proposed a national quarantine system. The proposal called for inspecting all incoming ships, conducting medical examinations of passengers and crews, and detaining under quarantine those thought to be infected. (The length of the quarantine was to be based on the incubation period of the specific disease in question.) These regulations were to be enforced by the Marine Hospital Service, the forerunner of the present U.S. Public Health Service (PHS).
Historically, there is no question that, as a public health measure, quarantine was relied upon more heavily than its practical value warranted. Detainment and isolation were extreme inconveniences to those affected; there was a stigma attached to being quarantined; the detection, restraint, and isolation of suspected cases of diseases that required quarantine were costly; and, because of the stigma, people failed to report their disease. Consequently, although quarantine was useful in controlling isolated outbreaks of human disease, and is still of value in combating epidemics of animal disease (if the animals thought to be infected are subsequently killed), for the most part quarantine policies did more harm than good.
Following World War II, the belief that the practice was of little use to modern disease control efforts began to gather support. A 1966 PHS advisory committee stated that "it is no longer possible to have confidence in the idea of building a fence around this country against communicable diseases, as is the traditional quarantine concept. The increasing volume and speed of international travel make this unrealistic" (Advisory Committee on Foreign Quarantine, 1966).
Following a reorganization of the PHS in 1967, the responsibility for