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The Difference Between Isolation and Quarantine

The Difference Between Isolation and Quarantine

There seems to be confusion between what it means to isolate versus quarantine people. According to the CDC, the definitions of isolation and quarantine are:

Isolation is used to separate ill persons who have a communicable disease from those who are healthy. Isolation restricts the movement of ill persons to help stop the spread of certain diseases, and is a routine procedure in hospitals and healthcare facilities. Isolation is voluntary; however, in a public health emergency, officials have the authority to isolate people who are sick.

Quarantine is used to separate and restrict the movement of well persons who may have been exposed to a communicable disease to see if they become ill. This can help limit the spread of the communicable disease. Quarantined people may stay at home or an area designated by the government (eg, border locations or military bases). Quarantine can be voluntary, but in a public health emergency, officials have the authority to quarantine people who have been exposed to an infectious disease.

Voluntary Isolation or Voluntary Quarantine is when someone isn't ordered to go into isolation or quarantine but chooses to do so out of caution.

History of Isolation and Quarantine:

  • The earliest mention of isolation is found in the Old Testament where several verses mandate isolation for those with leprosy.
  • In the 14th century, to protect cities from plague epidemics, ships arriving in Venice from infected ports had to sit at anchor for 40 days and fly a yellow flag before being able to land. The word quarantine was derived from the Italian words quaranta giorni, translating to 40 days.
  • In 1647, due to the plague, the Massachusetts Bay Colony restricted the docking of ships from the West Indies at Boston Harbor. Ships had to pause or risk a $100 fine.
  • By the 1660s, the first colonial quarantine laws were established.
  • By the 1700s, all major towns and cities along the eastern coast of the US passed quarantine laws, but the laws were only enforced when an epidemic appeared imminent.
  • In 1878, after the outbreak of yellow fever in Philadelphia, Congress passed laws that mandate involvement of the federal government in quarantine.
  • In 1907, Typhoid Mary (Mary Mallon) was required life-long involuntary isolation to prevent her from working as a cook and infecting others. She was the first person to be found to be a "healthy carrier" in the United States. She infected 47 people with typhoid feverthree of them eventually died.
  • In 1944, the Public Health Service Act was established to prevent the introduction, transmission, and spread of communicable diseases from foreign countries into the United States.
  • In April 2003, President George W. Bush added SARS to the list of quarantinable diseases, which also includes cholera, diphtheria, infectious tuberculosis, plague, smallpox, yellow fever, and viral hemorrhagic fever, such as the Ebola viruses.
  • In 2007, public health officials quarantined a 31-year-old attorney who was infected with a drug-resistant form of tuberculosis after traveling to Europe, despite knowing he hadand could spreadthe disease. Once back in the US, he was quarantined in Denver and had to report to the health department 5 days a week throughout treatment.
  • Today, individuals with suspected COVID-19, or those who have been in contact with a confirmed COVID-19 case, are asked to self-quarantine; those with confirmed COVID-19 are typically quarantined within a hospital.

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Filed under: Infectious Diseases, Public Health

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