Quarantine means separating a person or group of people who have been exposed to a contagious disease but have not developed symptoms from others who have not been exposed, in order to prevent the possible spread of that disease. Quarantine is usually established for the incubation period of the communicable disease, which is the span of time during which people have developed illness after exposure. For COVID-19, the period of quarantine is 14 days from the last date of exposure, because 14 days is the longest incubation period seen for similar coronaviruses. Someone who has been released from COVID-19 quarantine is not considered a risk for spreading the virus to others if they have not developed an illness during the incubation period.  With that said, someone who does develop symptoms and/or has been diagnosed as having contracted COVID-19 may require a period longer than 14 days.