In the US, vaccinated people can gather indoors, the CDC says.

Fully vaccinated Americans can now gather indoors, maskless and without distancing—as long as it’s with others who’ve gotten their shots, according to new guidance from the Centers for Disease Control and Prevention.

The advice, which comes as vaccinations continue to gain speed in America, are a positive signal for those who have had a course of shots. But it shows there’s a lot we still don’t know about how the virus behaves—and leaves plenty of questions about who can do what, and what’s fair. 

Three things the new CDC guidance says

• Indoor, maskless, and non-distanced gatherings are okay, as long as individuals have been fully vaccinated for at least two weeks. The CDC says medium and large gatherings should still be avoided, although it doesn’t specify a number of people for a small gathering.

• In public, keep your mask on and continue to distance from others. When you’re out and about in your community, on the train or at the grocery store, you might cross paths with people who haven’t been vaccinated yet.

• Vaccinated and unvaccinated people can gather together, with limitations. If you’re vaccinated, the CDC says you can visit indoors unmasked with unvaccinated people from one other household. There are important considerations discussed below, like the health profiles of the unvaccinated people involved.

Three things that are still unanswered

• Whether vaccinated people are still considered a transmission risk. We know that vaccinated individuals are much less likely to become infected, and much less likely to transmit the virus—but the CDC hasn’t yet advised what this means for people’s behavior. It’s crucial for vaccinated people to understand that interacting with others who haven’t been vaccinated or infected carries “an undefined, finite risk,” says Thomas Russo, professor of infectious diseases at the University of Buffalo. That risk of transmission may be decreased, but it’s probably not zero.

• Whether vaccines can prevent long-term effects of covid-19—and what they are. All vaccines approved for emergency use in the US have proved to be highly effective at preventing death, but we’re still learning about the long-term effects of covid-19. Even people with relatively minor cases could still battle symptoms for weeks or months. The safest bet, Russo says, is to do everything you can not to get infected.

• What your personal risk tolerance should be. Though the CDC guidelines say unmasked indoor gatherings are acceptable between a vaccinated person and unvaccinated people from one household, there’s a big caveat: whether anyone in the unvaccinated household is at an increased risk for severe illness from covid-19. 

  Even if you read up on the health conditions that are proved to increase risk, “there are still people that end up getting severe disease for reasons that we’re not certain about,” Russo says. “[The guidelines] count on the public to sort that out.” That risk calculation may be especially tricky if you live with some people who are vaccinated but others who aren’t. Russo, who is in a mixed household, says he is taking a conservative approach and being as careful as possible.

More of the same … for now

Though these new guidelines might give some families the peace of mind to organize much-needed visits with grandparents, not much changed today for the vast majority of the US—particularly for people of color. A New York Times analysis found Black people were undervaccinated relative to their population in each one of the 38 states that report on race and ethnicity for vaccinations. A gap exists for Hispanic people, too. And though the new CDC guidance applies only to private activities—not large-scale public reopening—bioethicists have warned that using vaccination status as a prerequisite to participating in reopening could further entrench existing racial inequities. 

“We need to make every effort [to ensure] that the vaccination process is equitable and fair,” Russo says. “And we’re still struggling.”

This story is part of the Pandemic Technology Project, supported by the Rockefeller Foundation.