quarantined

Quarantine is the separation and restriction of movement of individuals who may have been exposed to an infectious disease, to monitor whether they become ill and to prevent onward transmission. It differs from isolation, which applies to those who are known to be ill. Quarantine can apply to people, groups, or goods such as ships, animals, or commodities. It is typically ordered by public health authorities and may be implemented at homes, facilities, or border checkpoints. The duration usually corresponds to the disease's incubation period plus a safety margin, and guidelines are issued by authorities; in maritime and border settings, quarantine is often supported by legal powers and monitoring.

Historically, quarantine originated in port cities during plague outbreaks, derived from the Italian quaranta giorni, meaning forty days. Maritime practice established periods during which ships were kept isolated to prevent spread of disease. Over the centuries, quarantine has evolved with advances in epidemiology, communications, and international health regulations.

In modern public health, quarantine is one tool among surveillance, contact tracing, vaccination, and treatment. It raises ethical considerations, balancing civil liberties with protection of the population. Compliance is encouraged and may be mandatory, with provisions for essential activities, accommodations, and social support. Noncompliance can trigger penalties, but authorities also aim to provide clear information, medical care, and humanitarian considerations. Quarantines are most effective when they are proportionate, time-limited, and based on evidence about incubation periods and transmission dynamics.

Quarantined is used as an adjective describing the status of people, places, or objects placed under such measures, for example a quarantined ship or a quarantined individual. The term remains common in public health discourse and in discussions of outbreak response.