People who test positive for Covid-19 only need to isolate for five days as long as their symptoms have stopped, the United States Centers for Disease Control and Prevention said Monday, December 27, The Verge reports.

The change to isolation guidelines from 10 days to five is based on data showing people with Covid-19 are most likely to be contagious to others during the few days before and after they start showing symptoms, the agency said in a statement.

After leaving isolation, people should wear a mask around others for five additional days, the CDC said.

The CDC also said Monday that people who haven’t received a booster dose of a Covid-19 vaccine but received their second dose of an mRNA vaccine six months ago, or who received a Johnson & Johnson vaccine two months ago, should quarantine for five days if they’re exposed to someone with Covid-19. That’s a change from previous guidelines, which said people who are fully vaccinated don’t need to quarantine if they have exposure to someone sick with the disease.

The changes to isolation guidelines for people sick with Covid-19 come only a few days after the CDC said that health care workers only need to isolate for seven days if they test positive for the virus, as long as they’re asymptomatic and have a negative test on the seventh day. The United Kingdom also shortened its recommended isolation period to seven days, as long as people have negative tests on the sixth and seventh days.