The Centers for Disease Control and Prevention on Monday issued long-awaited advice to Americans fully vaccinated against Covid-19, freeing them to take some liberties that the unvaccinated should not, including gathering indoors in small groups without precautions while still adhering to masking and distancing in public spaces.
The agency offered good news to grandparents who have refrained from seeing children and grandchildren for the past year, saying that vaccinated people may visit indoors with unvaccinated people from a single household so long as no one among the unvaccinated is at risk for severe disease if infected with the coronavirus.
In practice, that means fully vaccinated grandparents may visit unvaccinated healthy adult children and healthy grandchildren of the same household without masks or physical distancing. But the visit should be local — the agency still does not recommend travel for any American, vaccinated or not.
The agency’s recommendations arrived as state officials move to reopen businesses and schools amid a drop in virus cases and deaths. Federal health officials repeatedly have warned against loosening restrictions too quickly, including lifting mask mandates, fearing that the moves may set the stage for a fourth surge of infections and deaths. According to a New York Times database, the seven-day average of new cases was more than 58,700, as of Sunday, a level that remains near the peaks reported last summer.
“With more and more people getting vaccinated, each day we are starting to turn a corner, and as more Americans are vaccinated, a growing body of evidence now tells us that there are some activities that fully vaccinated people can resume at low risk to themselves,” Dr. Rochelle Walensky, the C.D.C. director, said at a White House news conference on Monday.
But, she added, “While we work to quickly vaccinate people more and more each day, we have to see this through.”
The new advice is couched in caveats and leaves room for amendments as new data become available. The guidance is a “first step,” Dr. Walensky said. “It is not our final destination.”
The agency did not rule out the possibility that fully vaccinated individuals might develop asymptomatic infections and spread the virus inadvertently to others, and urged those who are vaccinated to continue practicing certain precautions.
Agency officials encouraged people to be inoculated with the first vaccine available to them, to help bring the pandemic to a close and a resumption of normal life. The agency emphasized that vaccines are highly effective at preventing “serious Covid-19 illness, hospitalization and death,” and said its guidance “represents a first step toward returning to everyday activities in our communities.”
As of Monday, about 60 million people have received at least one dose of a Covid-19 vaccine, including about 31.3 million people who have been fully vaccinated, according to the C.D.C. Providers are administering about 2.17 million doses per day on average.
The C.D.C.’s advice is aimed at Americans who are fully vaccinated, meaning those for whom at least two weeks have passed since they received the second dose of the Pfizer-BioNTech or Moderna vaccines, and those for whom at least two weeks have passed since receiving a single dose of the Johnson & Johnson vaccine.
What is safe for newly vaccinated Americans and their unvaccinated neighbors and family members has been uncertain in large part because scientists do not yet understand whether and how often immunized people may still transmit the virus. If so, then masking and other precautions are still be needed in certain settings to contain the virus, researchers have said.
There is also uncertainty about how well vaccines protect against emerging variants of the virus, and how long the vaccine protection lasts.
The C.D.C. said that “a growing body of evidence” suggests that people who are fully vaccinated are less likely to have asymptomatic infections and “potentially less likely to transmit the virus that causes Covid-19 to other people.” Still, the agency did not rule out the possibility that they may inadvertently transmit the virus.
Given the current state of research, the C.D.C. advised:
Fully vaccinated Americans may gather indoors in private homes in small groups without masks or distancing. Vaccinated people may gather in a private residence without masks or distancing with unvaccinated people, so long as they are from a single household and are at low risk for developing severe disease should they contract the coronavirus.
Vaccinated Americans need not quarantine or get tested if they have a known exposure to the virus, as long as they do not develop symptoms of infection. If they do develop symptoms, they must isolate themselves, get tested and speak with their doctors.
In public, vaccinated people must continue to wear masks, maintain social distance and take other precautions, such as avoiding poorly ventilated spaces, covering coughs and sneezes, washing hands often and following any other protocols that are in place.
Vaccinated people should avoid gatherings with multiple households, as well as large and medium-sized gatherings. (The agency did not specify what size constitutes a medium or large gathering.)
The C.D.C. did not revise its travel recommendations, continuing to advise that all Americans stay home unless necessary. Dr. Walensky noted that virus cases have surged every time there has been an increase in travel.
“We are really trying to restrain travel,” she said. “And we’re hopeful that our next set of guidance will have more science around what vaccinated people can do, perhaps travel being among them.”
Noah Weiland contributed reporting.