Fully vaccinated? Here’s why (and when) you should still wear a mask.

So, you got fully vaccinated - congratulations! You’re among a small group of people in the United States almost entirely protected from hospitalization and death related to COVID-19.

The great news? New CDC guidelines say that fully vaccinated people can safely spend time inside without masks with other vaccinated people. The guidelines also give vaccinated people clearance to hang out with low-risk, unvaccinated people from one other household. 

That said, even though you’re protected now, it is likely that you have family, friends, or colleagues who are not vaccinated yet. Because of the high number of COVID-19 cases, we recommend that vaccinated people continue to wear masks and maintain physical distance in public spaces and with unvaccinated people. This is a temporary recommendation until more people in the community get vaccinated. 

Here are five reasons why you should keep distancing from unvaccinated people from multiple other households and wearing masks in shared spaces after being vaccinated:

  1. Efficacy, or the protection vaccines offer against any COVID-19 infection in clinical trials, is estimated to be 94.1% for the Moderna vaccine, 95% for the Pfizer vaccine, and 66.9% for the Johnson & Johnson vaccine. That said, certain populations not represented in the trials--including pregnant women, people who are obese, and those living with cancer--may not be as well protected. 
  2. Immunity. After getting the second dose, it takes 2 to 3 weeks for your body’s immune response to fully develop. Once established, immunity may decline over time. The duration of vaccine immunity against COVID-19 is not certain: it could require an annual shot to protect against multiple strains or a booster after multiple years. 
  3. Transmissibility after inoculation, or whether someone who is vaccinated can be asymptomatic and spread the virus, seems to be somewhat limited. But we’re still studying just how common this is after a person gets vaccinated. New strains of COVID-19 might impact this transmission potential.
  4. Herd immunity is the percent of the population either infected or inoculated that is needed to control a pandemic. Experts estimate at least 70% of the population would need to be vaccinated against COVID-19. In the U.S. that would be over 200 million people. Until we are all vaccinated, the virus can continue to spread.
  5. Modelling safe practices is a good way to establish new social norms. Continuing to wear a mask and maintaining 6 feet of distance makes it easier for those still awaiting their vaccine to do the same.

What’s the bottom line?

We need more people to get vaccinated and scientists want to learn more about how the vaccine works in real world settings before we can entirely lift measures that prevent COVID-19 from spreading in the community. 

Last update: 9 March 2021, 11:30 EST

Science review: SKB, GSN