Pop Culture dictionary

contact tracing

[ kon-takt trey-sing ]

What is contact tracing?

Contact tracing is a practice where anyone who may have come into contact with a person infected with a communicable disease is identified, interviewed, monitored, and, often, quarantined. Contact tracing is done to prevent the spread of infectious diseases.

In medicine, a contact is a person who has been exposed to an infected person. Contacts are traced, meaning they are discovered and watched for health purposes.

While contact tracing is a tried-and-true technique in infectious disease control, the term gained widespread awareness and currency during the outbreak of COVID-19 in 2020. The virus that causes COVID-19 is very contagious, and so contact tracing has been one of the methods (along with social distancing) used to help stop or slow its spread.

Related words

wet market

Where does contact tracing come from?

While forms of the practice are older, the term contact tracing is first recorded in the 1930s. During World War II, contact tracing was used to track the spread of sexually transmitted diseases. Contact tracing was also notably used to help control and prevent the spread of such communicable diseases in the 20th and 21st centuries, including smallpox, AIDS, SARS, and Ebola, and COVID-19.

So, what, exactly, is contact tracing, and how does it help fight the spread of communicable diseases? It involves three primary stages:

  1. When someone is confirmed or suspected to have a communicable disease, they are thoroughly questioned by trained individuals to find out who they might have interacted with—and thus may have spread the disease to—after becoming infected.
  2. These people, known as contacts, are identified and made aware of their exposure (e.g., via phone or email) to get any healthy and safety information they might need. This could include symptoms of the disease and what they should do if they think they might have it.
  3. The contacts get regular follow-ups so they can be monitored and tested if they show symptoms of the disease.

The goal of contact tracing is mitigation and prevention—to slow or stop the spread of communicable diseases. For some infectious diseases, a person exposed to someone who is infected has to quarantine; if they themselves become infected, they are isolated. Learn more about the difference between quarantine vs. isolation.

While a labor-intensive process, contact tracing has proven highly effective at identifying people who have been exposed and infected, allowing public health officials to monitor their condition and treat them before they can spread the disease to anyone else.

Contact tracing has been at the forefront of medical strategy (and news headlines) during the outbreak of the COVID-19 virus as a way to help prevent the spread of this highly contagious disease. Many governments and organizations around the world have been using contact tracing to try and slow the spread of the novel coronavirus, and ensuring a certain number of contact trainers in the population has been a part of requirements for lifting shelter-in-place restrictions. Medical organizations, such as the Centers for Disease Control and Prevention (CDC) and Johns Hopkins Bloomberg School of Health, have provided free resources for people hoping to train themselves in contact tracing.

Contact tracing does have its challenges, as highlighted during the outbreak of COVID-19. For one thing, contact tracing takes time, and if a disease is especially contagious (as COVID-19 is), it can spread far and fast, making it hard for contact tracing to keep up—underscoring why early and thorough contact tracing is important. For another thing, if an infected person doesn’t show any symptoms (as was the case with some infected with COVID-19), challenging the effectiveness of contact tracing—making diagnostic testing for the disease all the more vital.

To conduct contact tracing, health workers need a lot of personal information, which have led to some objections to the practice as an invasion of privacy (especially when it comes to the use of tracking the movement of contacts using GPS technology on their mobile phones).

Examples of contact tracing

Researchers say the US—or really any country—can't safely reopen without significant amounts of contact tracing and testing.
Holly Yan, CNN, April 2020
Dr. Fauci on coronavirus contact tracing: "We've got to do it better than we are now... When you have someone in society who is infected, you've got to not only identify them, but you've got to be able to isolate them very quickly, not five days later."
@ryanstruyk, March 2020

Who uses contact tracing?

A person who performs contact tracing is called a contact tracer. They could be, for instance, a professional (such as a nurse or medical assistant) or a volunteer who has been trained in contact tracing. Contact trace is sometimes used as a verb form for the act of contact tracing.

Prior to 2020, contact tracing was a phrase that would have been most familiar to medical professionals (such as epidemiologists) and public health officials (as at the CDC and WHO, which focus on fighting communicable diseases).

Contact tracing became a household term in 2020 after many news outlets explained what it was, and why it is important, in stories about the COVID-19 virus.

What other words are related to contact tracing?

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This is not meant to be a formal definition of contact tracing like most terms we define on, but is rather an informal word summary that hopefully touches upon the key aspects of the meaning and usage of contact tracing that will help our users expand their word mastery.