What you need to understand about the CDC’s COVID isolation guidelines

Why rapid testing is not required for shorter isolation period

DETROITThe CDC is still struggling to clarify its change in the recommended isolation period for people who test positive for COVID but are asymptomatic.

Dr. Frank McGeorge said in an effort to return more essential workers to the workplace faster, the CDC has created a lot of unnecessary confusion.

Their latest update states that if you want to take a rapid test at the end of a five-day isolation period, you can. But it’s not required.

Why isn’t the CDC requiring a rapid test as part of the shortened isolation period?

Read: Michigan will update COVID quarantine guidance to match CDC

Dr. Rochelle Walensky said the tests are only authorized for detecting whether or not someone has an infection -- not how contagious they might be. They’re most useful when taken repeatedly on multiple days.

“It became clear that people were interested in using rapid tests, though not authorized for this purpose, after their end of isolation period and because there was interest in using them for this reason -- we then provided guidance on how they should be used,” Walensky said. “If one is to take an extra step and perform a test at the end of their five-day isolation period, we wanted to make sure people understood how they should be interpreted. If that test is positive, people should stay home for those extra five days and if that test is negative people really do need to understand that they must continue to wear their mask for those extra five days to complete a 10-day isolation period.”

  • CDC recommends shortening quarantine and isolation duration for those who aren’t vaccinated or haven’t received booster to five days followed by an additional five days of wearing a well-fitting mask around others.

Read: US advisers endorse Pfizer COVID boosters for younger teens

That masking requirement is very important.

Estimates on how many people are still infectious after day five vary wideline, but data from the U.K. suggests it could be as high as 31%. The safest way to ensure you’re not contagious to others is still to isolate for ten days.

There will be a significant number of people who are still able to spread the virus to others after five days. Using rapid tests can give you another piece of information, but regardless of what it says you may still be infectious. You will need to take steps to protect others if you stop isolating, including a good tight-fitting mask.

If PCR tests are most accurate, why isn’t the CDC recommending people get one of those before leaving isolation? For this purpose, the PCR tests are actually too good. They are so sensitive they can pick up tiny pieces of the virus long after people are no longer contagious.

Read: Complete Michigan COVID coverage

About the Authors:

Dr. McGeorge can be seen on Local 4 News helping Metro Detroiters with health concerns when he isn't helping save lives in the emergency room at Henry Ford Hospital.

Kayla is a Web Producer for ClickOnDetroit. Before she joined the team in 2018 she worked at WILX in Lansing as a digital producer.