The CDC eased its mask-wearing and social-distancing guidance for fully vaccinated people. Here’s what you need to know

The CDC announced Thursday that “anyone who is fully vaccinated can participate in indoor and outdoor activities, large or small, without wearing a mask or physical distancing.”Lane Turner/Globe Staff

The Centers for Disease Control and Prevention announced a major step in the country’s return to normalcy on Thursday with updated guidance on mask-wearing and social distancing for fully vaccinated people.

During a White House COVID-19 briefing, CDC director Dr. Rochelle Walensky said the agency now recommends that “anyone who is fully vaccinated can participate in indoor and outdoor activities, large or small, without wearing a mask or physical distancing.”

What are the new rules?

If you’ve been fully vaccinated, “you can resume activities without wearing a mask or staying 6 feet apart, except where required by federal, state, local, tribal, or territorial laws, rules, and regulations, including local business and workplace guidance,” the CDC’s website states.

A person is considered fully vaccinated two weeks after they have received their final vaccine dose.

Are there exceptions?

Walensky noted that masks are still required for fully vaccinated people when traveling on buses, trains, and other forms of public transportation as well as in airports and stations.

“You will still be required to wear a mask on planes, buses, trains, and other forms of public transportation traveling into, within, or out of the United States, and in US transportation hubs such as airports and stations,” the agency’s website says.

The CDC guidance notes that while it is safe for fully vaccinated people to stop wearing a mask or social distance in any setting, mask-wearing should be guided by measures put in place by state and local governments.

A mask mandate is still in effect in Massachusetts. It requires people in the state to wear masks in indoor public places and outdoors when they are unable to maintain 6 feet of distance from others.

People who have compromised immune systems should speak to their doctor before giving up their mask, Walensky said.

She noted that due to the unpredictability of the virus, “there is always a chance we may need to make a change to these recommendations.”

“But we know that the more people are vaccinated, the less cases we will have and the less chance of a new spike or additional variants emerging,” Walensky said.

What happens if I get symptoms, or if I am unvaccinated?

If people develop symptoms of COVID-19, they should start wearing a mask again and get tested for the virus, Walensky said.

She also emphasized that the updated guidance only applies to people who are fully vaccinated, and there are still risks for those who have not yet had their shots.

“The science is also very clear about unvaccinated people: you remain at risk of mild or severe illness or death, or spreading the disease to others. You should still mask, and you should get vaccinated right away.”

After more than a year of wearing masks, Walensky noted that the announcement of the new guidance marks an “exciting and powerful moment.”

“Once you are fully vaccinated, two weeks after your last dose, you can shed your mask,” she said.

What about kids?

Children under 12 years old are not eligible to be vaccinated and will still need to wear masks.

The CDC’s website says children 2 years old and older need to wear masks to avoid contracting or spreading the virus.

The Food and Drug Administration this week authorized Pfizer’s COVID-19 vaccine for adolescents 12 to 15 years old, paving the way for millions more in the country to get vaccinated.

In Massachusetts, those in the age group began receiving shots on Thursday.