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May 20, 2020

Ask the expert: What is contact tracing?

Due to COVID-19, “contact tracing” has been added to our vocabulary. Not everyone understands it is essential to stopping the spread of the novel coronavirus. Mieka Smart, assistant professor in the Department of Epidemiology and Biostatistics and the Division of Public Health in the College of Human Medicine, answers questions about contact tracing. She received her public health training at Johns Hopkins University and is a member of the COVID-19 Contact Tracing Workgroup for Flint/Genesee County.

What is contact tracing?

When a person has tested positive for COVID-19, they are asked for a list of people that they have recently been in close contact with. Contact tracing is the effort to get in touch with the people on that list and let them know that they were potentially exposed. They are given coaching on how to take extra precautions, beyond simply staying at home in self-quarantine.

How does it work and what do Americans need to do to comply?

Americans need to know that a call from a contact tracer will not always mean that you need a COVID-19 test and that the vast majority of the contact tracing effort will happen on the phone. Thousands of health professionals are currently being trained on how to make these phone calls. To comply with contact tracing efforts, it will be important for you to answer calls that come from the state, city or county in which you live. Although you may not recognize the phone number, the person calling may be trying to alert you to exposure and, therefore, trying to save your life.

Why is contact tracing necessary for public health reasons?

It is estimated that a person with COVID-19 will likely infect two to three others. If one person spreads the virus to three others and then each of those people spreads it to three more people, it will keep spreading at that rate. Without contact tracing, it is very likely that one person with COVID-19 can cause a ripple effect of more than 59,000 cases over time.

Are there personal rights and privacy risks to contact tracing?

There are no privacy risks when the contact tracing protocols are followed. The people who are doing the contact tracing are required to be registered with the state, complete a training module and sign a nondisclosure agreement. They are required to handle COVID-19 information with the same privacy we have always expected from employees in the health workforce. 

Is contact tracing necessary?

Contact tracing is one of the three critical actions necessary to eliminate COVID-19. The other two are diagnostic testing for everyone who has symptoms and widespread random blood testing to understand how/if people are building immunity.

By: Kim Ward