Vaccinated? It might be safe to see friends, but don’t throw out that mask.

Illustration by Alison Booth/Northeastern University

Of the roughly 18 percent of people in the United States who have received at least one dose of a COVID-19 vaccine, many are wondering: What now? Can I safely see my grandparents? My unvaccinated friends? Should I still wear a mask? And how long does it take to develop full immunity? 

On Monday, the Centers for Disease Control and Prevention published safety recommendations for vaccinated individuals. Northeastern’s Brandon Dionne, assistant clinical professor in the School of Pharmacy, and Neil Maniar, professor of the practice and director of the Master of Public Health program, explain the main takeaways from the guidelines.

What does it mean to be “fully vaccinated?”

“This is one of the most important points from the guidelines: You won’t develop the antibodies and have the maximum immunity until two weeks after your last dose,” says Dionne. 

For the single-dose Johnson & Johnson vaccine, maximum protection is reached two weeks after inoculation. And for the two-dose Pfizer or Moderna vaccines, maximum protection is reached two weeks after the second dose. 

Even after reaching full immunity, there always will be some possibility that individuals contract COVID-19 (vaccines range from 72 percent to 95 percent effective at preventing moderate to severe disease). But the chances of developing COVID-19 drop significantly 14 days after receiving the last dose.

What can you do if you’re fully vaccinated?

One thing is clear: “A vaccine is not a ticket for large unmasked indoor gatherings,” Maniar says. “But it is an opportunity for people to come together in small ways.” 

The CDC says it’s safe for fully vaccinated people to visit with other fully vaccinated people indoors without wearing masks or physically distancing. However, limiting the size of these gatherings is still advised, Maniar says. 

“There’s a difference between four vaccinated people getting together and 50 vaccinated people getting together,” he continues. “There’s still a marginal risk that vaccinated people will get COVID, and that risk multiplies when there are more people together.”

Plus, there’s still the issue of variants. “We are still gathering evidence about how effective these vaccines are against certain variants,” Maniar says. “But those are just against the variants we know about.” 

For example, a new study shows that the Pfizer and Moderna vaccines were at least 10 times less effective against B.1.351, otherwise known as the South African variant, though this title is a misnomer as the variant is now spreading worldwide, including in the U.S.  

As for interacting with people who haven’t received the vaccine, the CDC says it’s safe for vaccinated people to visit unvaccinated people from a single household who are not at risk of severe COVID-19. Masks and physical distancing, even indoors, are not necessary. 

“From a single household” and “not at risk” are the keywords here. While there is some evidence that COVID-19 vaccines reduce the possibility of transmission, the potential for transmission is still not zero. 

Finally, the CDC also says vaccinated people can refrain from quarantining and testing following a known exposure if they are asymptomatic. A growing body of research suggests that vaccinated individuals are less likely to develop asymptomatic cases, in which case quarantining and testing are not necessary unless an individual shows symptoms. 

“The important thing is that now people can start to break through the social isolation that has been so difficult for so many over the past year. Family members can see each other. Vaccinated grandparents can see their grandkids,” Maniar says.

What can’t you do if you’re fully vaccinated?

Vaccinated people can’t completely abandon their masks or cozy up to everyone just yet. The CDC still advises that people wear well-fitted masks and maintain social distancing in public and while interacting with unvaccinated people who are at risk for severe COVID-19.

And if vaccinated people are experiencing symptoms, they should still get tested and stay home.

Are some vaccines better than others?

The recently approved vaccine by Johnson & Johnson is 72 percent effective at preventing moderate to severe cases of COVID-19. Moderna’s vaccine is 94 percent effective,  and Pfizer’s is 95 percent effective.

But Maniar and Dionne can’t stress this enough: People should get whichever vaccine is available, regardless of efficacy.

“Don’t shop around. When you have the opportunity to get the vaccine, get whichever one is offered,” Maniar says.

For those reluctant to get the Johnson & Johnson vaccine, Dionne puts it into perspective: “If you’re gathering with your friends, and everyone is fully vaccinated, even if you have the misfortune of getting COVID-19 from someone you gathered with, it doesn’t matter which vaccine you got, because all three vaccines protect you from the worst possible outcomes.”

All three vaccines prevent hospitalization and COVID-19-related deaths in the vast majority of cases.

Plus, vaccinated people seem to be less likely to become infected with the virus, including asymptomatic infections, which means they’re less likely to transmit the disease, regardless of which vaccine they received.

Another pro that far outweighs the con of receiving a slightly less effective vaccine is that as the population comes closer to herd immunity, restrictions will become more relaxed, and the things that people miss so dearly—eating out, seeing friends, even just seeing other people’s faces—will become safer, Dionne says.

“People are starting to see the light at the end of the tunnel,” he says. “Hopefully it’s enough to incentivize people to get a vaccine, any vaccine.”

For more information regarding COVID-19 vaccine protocols, visit the CDC’s guideline page

For media inquiries, please contact Jessica Hair at or 617-373-5718.