Updated COVID-19 isolation and quarantine guidance

In late December 2021, the CDC changed its isolation and quarantine guidelines.

The changes are motivated by research demonstrating that most COVID-19 transmission occurs early in the course of illness, generally 1-2 days before the onset of symptoms and 2-3 days after.

The guidelines depend on the person’s vaccination status. Someone is considered “up to date” if they have received a booster shot or completed their primary immunization with Pfizer or Moderna within the last six months (two months for J&J). If someone has not received a booster, completed their primary vaccine more than six months ago for Pfizer or Moderna (two months for J&J) or is not vaccinated at all, they are considered not “up to date.”

If someone is exposed to COVID-19, they should quarantine (stay home and wear a well-fitted mask if they must be around others in their home).

• Those who are up to date with their COVID-19 vaccines (or had confirmed COVID-19 in the last 90 days) do not need to quarantine unless they develop symptoms. They should wear a mask around others for 10 days and test on day 5 if possible. If they develop symptoms, they should isolate and get tested immediately.
• Those who are not up to date with their COVID-19 vaccines should quarantine for at least five full days and continue to wear a mask around others for five additional days. Even if they do not develop symptoms, they should get tested on day 5. If they develop symptoms, they should isolate and get tested immediately.

If someone tests positive for COVID-19 or is showing symptoms, they should isolate (stay home, separate from household members and wear a well-fitted mask if they must be near others).

• Those who have tested positive for COVID-19 or have symptoms should isolate for five days regardless of vaccination status. They can end isolation after five full days if they are fever-free for 24 hours (without using a fever-reducing medication). They should continue to wear a mask around others for five additional days.
• Those who have tested positive for COVID-19 but do not have symptoms should isolate for five days after they test positive. They should continue to wear a mask around others for five additional days.
• Those severely ill with COVID-19 should isolate for at least 10 days and consult their doctor before ending isolation.

Source: CDC