Quarantine: voluntary or not?

By utilizing quarantine and isolation as public health tools we are in many ways battling twenty-first century pathogens with a fourteenth century toolbox. It is important for all to recognize the technical difference between the distinct public health measures of isolation and quarantine. Isolation is the separation and/or restricted movement of persons with a contagious disease from the larger population. Quarantine is a separation and restriction placed on the movement of persons presumed to have been exposed to a contagious disease or suspected to be a carrier of a contagious disease. Although these are distinct health measures, they are often both addressed through the state quarantine laws. From a modern public health perspective, the best way to implement isolation and quarantine is through voluntary means, although in some cases compulsory means may be required. Ideally, isolation and quarantine are most effective through the early detection of contagious disease cases and identification of possible carriers. Isolation enables the authorities the ability to conduct contact tracing from infected individuals and may result in the home quarantine of these exposed contacts. Contact tracing is a resource-intensive undertaking and this reality was underscored by the global experience with SARS in 2003. Out of necessity, public health agencies generally relied on home quarantine for the close contacts of SARS patients and only utilized institutionalized quarantine for selected populations at risk who did not have suitable home environments in the vicinity. Work quarantines were occasionally applied to health care workers. Quarantine measures effectively enable health authorities to remove affected persons from subsequent chains of transmission. In the twenty-first century, isolation and quarantine actions taken by public health officers are a delicate balance between the public good and individual liberties. Generally, the states are responsible for the regulation and enforcement of public health controls within their own borders. Throughout the fifty states, there is a significant variation of quarantine and isolation laws and many of them predate the advent of modern epidemiology principles. The powers held by the federal government to implement isolation and quarantine are limited primarily to the control of eight communicable diseases enumerated in federal executive orders and apply to international arrivals and persons engaging in interstate movement. In addition to these circumstances, the US. Department of Health and Human Services can intervene within states to enact isolation and quarantine if the state requests such intervention or if it recognizes a state has failed in its containment efforts. In issues where a specified communicable disease may affect interstate commerce, the federal government also retains the power to assert its authority by directing control measures. Controlling the movement of conveyances either at ports of international arrival or interstate is more broadly authorized than restricting the movement of individuals which is restricted to the eight diseases specified by Executive Order. In the recent SARS outbreak, public health officers in Toronto utilized voluntary quarantine and isolation measures to control its spread. The populace of over 27,000 affected persons was overwhelmingly cooperative with these requests. Based on this experience, it is not accurate to simply assert “the public will not accept quarantine measures,” as some critics suggest.