Quarantine is a blunt tool to use in the control of infectious diseases, but it may be one of the only tools available when public health and medical analyses indicate the need to act quickly. Quarantine can be used in addition to other disease control measures, and it is important that public health professionals refine exposure criteria to ensure people are not unnecessarily quarantined.
Modern quarantine is rarely applied to entire cities or communities, but rather it confines individuals who have recently come in contact with an individual exhibiting signs of illness. It is usually a form of home isolation, with some limited movement restrictions, and it is intended to reduce transmission by increasing the social distance between persons (see Figure 1).
The term quarantine derives from an ancient practice in which ships carrying people with contagious diseases were stopped at sea to prevent them from landing and spreading disease onshore. The first quarantine laws were enacted in colonial America to curb epidemics of smallpox and other infectious diseases. Quarantine laws have continued to evolve with advances in scientific understanding of infectious diseases, and the rules governing quarantine are complex.
The power to impose quarantine, provided under Section 361 of the Public Health Service Act, is generally interpreted to allow federal and state health authorities to apprehend and detain or require the conditional release of an individual if the Surgeon General finds that there is reason to believe that the introduction into the United States or across state lines of a communicable disease may threaten the public’s health. However, courts have frequently found that such orders are unreasonable or that authorities did not follow adequate procedures in imposing them.