This post has been updated.
The Centers for Disease Control and Prevention (CDC) has updated the COVID-19 quarantine protocols we’ve come to know and dread this past year. Until now, the CDC has stood by its recommendation that anyone who has been exposed to COVID-19 should self-isolate for a period of 14 days. Now, the health agency has added two additional self-isolation scenarios, both of which shorten that quarantine time with some added caveats.
Now, anyone who thinks they may have been exposed to the virus has three options for self-isolating. The CDC still strongly recommends that people adhere to the established 14-day quarantine period, which is based on evidence that the virus can incubate for up to 14 days before an infected person shows symptoms.
But the CDC now says that individuals can choose to quarantine for just 10 days, and end their isolation at that point if they haven’t yet shown symptoms. This is based on the fact that most (though not all) people who are going to display COVID-19 symptoms will start experiencing them before this point. Research over the past several months has found that the median incubation period for the virus is five days, and, on average, 97.5 percent of people exposed to the virus show symptoms by day 12.
Finally, a person can also choose to self-isolate for just seven days, and then get a COVID test (rapid or PCR). If that test comes back negative, they can end their isolation.
With these new options, it’s important to remind ourselves of the distinctions between quarantine and the other processes we’ve become most familiar with over the past eight months: Quarantine is the practice of self-isolating when you may have been exposed to COVID-19, so you don’t pass it on unintentionally; social distancing is the practice of remaining physically distant from those not in your household in order to reduce the likelihood of catching or transmitting COVID-19; and finally, isolation is staying away from all other people because you definitely have COVID-19 and are contagious.
The revised CDC guidelines in this case address quarantine procedures only. The social distancing measures we’re all familiar with now—physical distancing, masking, and regular hand washing—remain in place.
This shift might help make the quarantine period more palatable and doable, especially as we enter the holiday season. In theory, anyone who travels for the holidays—or even just spends time in close contact with people they don’t life with—should quarantine before and afterward to limit risk of transmitting COVID to others. Health officials hope that offering individuals options that seem less daunting than two weeks will lead to more people self-isolating and testing. While two weeks is still the safest quarantine period, the new guidelines may encourage some level of precaution among people who otherwise wouldn’t have isolated themselves at all.
“Reducing the length of quarantine may make it easier for people to take this critical public health action by reducing the economic hardship associated with a longer period, especially if they cannot work during that time,” Henry Walke, the incident manager for the CDC’s COVID-19 response, said in a press call on December 2.
Last week, Walke told The Wall Street Journal that the organization was considering a shorter isolation period. “We do think that the work that we’ve done, and some of the studies we have and the modeling data that we have, shows that we can, with testing, shorten quarantines,” Walke said.
“Fourteen days has always kind of been the magic period,” Georges Benjamin, executive director of the American Public Health Association, told Popular Science. “It was the best way to capture the time from exposure to development of disease.”
As our understanding of COVID-19 and our ability to test for it changes, he says, nobody should be surprised to see quarantine guidelines evolving. “We should anticipate that we’ll have continued refinements in a whole range of the guidances as we learn more,” he says.
“It’s been a very long and tough year for many people,” says Michelle Patch, a professor at the Johns Hopkins School of Nursing. If science supports the idea of shortening quarantine times, she says, that—coupled with weeks of positive news about COVID-19 vaccine development—might help raise morale during the holiday season and encourage people to continue practicing social distancing measures.
The key is in communication, Benjamin says. “The more we can refine [public-health guidance] and then articulate it in a way that everybody can understand, we’re much more likely to get better compliance. And if we get better compliance, at the end of the day we’ll get better disease control.”
A version of this article was originally published on November 25. It has been updated.