July 21, 2021: Since this article was originally published, new variants of the SARS-CoV-2 virus have become prevalent. Vaccination continues to be highly protective against serious illness, hospitalization, and death, even with the more transmissible Delta variant. But we’ve changed some of our recommendations about masking and other precautions for vaccinated individuals in certain situations, even when precautions are not required. Read more.
MIT Medical answers your COVID-19 questions. Got a question about COVID-19? Send it to us at CovidQ@mit.edu, and we’ll do our best to provide an answer.
I’m fully vaccinated and confused about what the CDC is saying is safe for me and for others.
A year ago, the CDC told us we should all wear masks to protect others. Now they are saying that vaccinated people can take their masks off, but unvaccinated people should continue wearing masks to protect themselves.
I’d love to take off my mask, but after a year of being nervous, I’m just not sure how much risk I still have. Is the CDC saying that vaccinated people are so well protected that they are not at risk, even if unvaccinated people don’t wear masks? That if I were in an indoor space with unvaccinated people, they would be the ones at risk and not me?
Yes, that is exactly what the CDC is saying. As a fully vaccinated person, you are very well protected. If you are exposed to the virus, your risk of developing symptoms is very low. Your risk of becoming severely ill or dying is lower still.
That sense of safety for vaccinated individuals is reflected in the CDC’s guidance for choosing safer activities, a webpage that gives examples of safe indoor and outdoor activities for vaccinated and unvaccinated individuals.
Unfortunately, if you’re not fully vaccinated, there’s not much you can do “safely.” You can feel free to unmask outdoors with members of your own household or in a gathering of fully vaccinated people, or mask up and join an outdoor gathering that includes other unvaccinated people. Your face covering will provide you with some protection in any situation, but even with a mask, other outdoor activities carry some risk, and no indoor activity can be considered “safe.”
The situation is quite different if you’re fully vaccinated. The CDC notes that vaccinated individuals should continue to follow local or site-specific requirements for face coverings, such as those still in effect at MIT or at other locations in Massachusetts. However, the public health agency is quite clear that unmasked, fully vaccinated people are quite safe in any environment and while participating in any activity — everything from being part of the crowd at a full-capacity sporting event to participating in an indoor, high-intensity exercise class.
Study after study has demonstrated vaccine effectiveness. A comprehensive CDC review of the evidence concludes that “COVID-19 vaccines currently authorized in the United States have been shown to be efficacious and effective against SARS-CoV-2 infections, including asymptomatic infection, symptomatic disease, severe disease, and death.” The report cites more than 40 studies demonstrating that currently authorized COVID-19 vaccines offer protection against known emerging variants. While there is a real but relatively small possibility that vaccinated people can still become infected and transmit the virus — MIT has identified such cases in its own testing program — the report points to evidence for reduced viral load in these so-called “breakthrough cases.” This makes these individuals less likely to be symptomatic or seriously ill and less likely to transmit the virus.
It’s now more dangerous than ever to remain unvaccinated. Even after a year and a half, SARS-CoV-2 is still a novel virus, and humans haven’t gotten any better at fending it off or fighting an infection. On the other hand, the virus has continued to evolve, becoming both more transmissible and more deadly. The Alpha variant, formerly known as B.1.1.7 and first reported in Britain, is now the most prevalent form of the virus in the United States. Compared to the original form of the virus, the Alpha variant is estimated to be about 50 percent more transmissible and between 40 and 70 percent more lethal.
But if you thought Alpha was bad, meet Delta. This variant, formerly known as B.1.617.2 and first identified in India, is thought to be 60 percent more transmissible than Alpha and is even more likely to lead to severe illness and hospitalization.
The Delta variant may be relatively new to the US, but it’s been running rampant elsewhere for several months. Overtaking Alpha quickly, Public Health England estimates that Delta now accounts for more than 90 percent of new COVID-19 illness in the United Kingdom, leading England to delay its full reopening by a month. In the US, the Delta variant comprised only about 10 percent of all sequenced cases when the CDC labeled it a variant of concern earlier this week, but it’s doubling every seven to 10 days, putting it on track to become the dominant variant in this country within about three weeks.
The good news is that vaccination appears to protect against even this newest variant of concern. While studies have so far examined the effectiveness of only Pfizer, Moderna, and AstraZeneca vaccines against the Delta variant, it’s likely that other COVID-19 vaccines will be similarly protective. For example, a just-published study of the J&J vaccine showed it to be highly protective against the Alpha variant, as well as variants first discovered in Brazil (Gamma), South Africa (Beta), and Southern California (Epsilon), primarily due to a robust T-cell response.
All that said, “reentry anxiety” is real. After, as you put it, “a year of being nervous,” it can be difficult to feel safe, even if the science assures you that you are. And you’re not alone; in a survey done by the American Psychological Association, roughly half of the more than 3,000 respondents reported feeling uneasy about resuming in-person interaction, regardless of vaccination status. So, while it’s important to start taking some first steps back into a more normal life, give yourself permission to take it slow. Keep moving forward, but do so at the pace that works for you.