“Previously, the CDC defined a close contact as someone who spent 15 minutes or more within six feet of someone contagious with COVID-19,” Leann Poston, MD, MBD, MEd, a physician with Invigor Medical, a men’s health clinic based in Washington State, tells Verywell. “This was an arbitrary definition that was put in place to have a benchmark to work with when contact tracing.”
But the CDC updated its guidance after reviewing footage of a corrections officer in Vermont who came in contact with an infected inmate over multiple short periods of time but was never in prolonged contract with the inmate, according to the report. The corrections officer later contracted COVID-19.
“The correctional officer reported no other known close contact exposures to persons with COVID-19 outside work and no travel outside Vermont during the 14 days preceding illness onset,” the CDC’s report noted.
The updated guidance now defines close contact as “someone who was within 6 feet of an infected person for a cumulative total of 15 minutes or more over a 24-hour period, starting from two days before illness onset (or, for asymptomatic patients, two days prior to test specimen collection) until the time the patient is isolated,” according to the CDC’s website.
Why the Change?
The CDC’s report highlights the need for health professionals to consider each contact a person with COVID-19 may have had with people while they were infected, Poston says.
“Since the aggregate of many small interactions over a 24-hour period has been found to be enough for the virus to spread, exposure notification models and contact tracing protocols need to be adjusted,” says Micha Benoliel, co-founder of Coalition Network Foundation, a non-profit that promotes free, open-source solutions to combat the spread of COVID-19. “Each short interaction is now important to tabulate in 24-hour aggregate cycles to get a full picture in the process of contact tracing and exposure notification,” he tells Verywell.
A few things that haven’t changed? The continued importance of mask-wearing, social distancing, and regular hand-washing, especially while researchers continue to work to better understand COVID-19 and the methods by which it is spread.
What This Means for Contact Tracing
For starters, what is contact tracing anyway? Put simply, contact tracing is a process used by health departments to, you guessed it, trace the origins of a COVID-19 infection.
Contact tracers work with communicable disease patients to get in touch with anyone they may have been in contact with, recommending isolation and quarantine when necessary.
The CDC’s expanded definition of “close contact" could make contact tracing tricky, Poston says.
“This change is going to make contact tracing more difficult especially for employees who might be in contact with multiple people for short periods of time during the day,” she says, adding that this includes people who work in schools, prisons, or retail businesses.
The information in this article is current as of the date listed, which means newer information may be available when you read this. For the most recent updates on COVID-19, visit our coronavirus news page.
