May 24, 2021 -- The Centers for Disease Control and Prevention's (CDC's) latest guidance on what fully vaccinated people can do safely — including not socially distancing and not wearing a mask indoors or outdoors unless other regulations require it — have been widely misinterpreted and caused confusion, said two infectious disease experts at a Thursday briefing hosted by the Infectious Diseases Society of America (IDSA).
The CDC did not ''lift" the mask mandate, but rather supplied guidance for those who are fully vaccinated. However, many questions and gray areas remain, and the experts addressed those. ''The CDC guidance is really directed at people who are fully vaccinated and who we know are likely to have a really solid response to the vaccine," said Jeanne Marrazzo, MD, MPH, director of infectious diseases at the University of Alabama at Birmingham and an IDSA board member.
That message was largely lost, said Marrazzo and Jeffrey Duchin, MD, health officer of public health for Seattle and King County, Washington, and also an IDSA board member. Duchin said many people mistakenly regarded the new guidance as a message that the pandemic is over.
Among their practical tips on how to interpret the guidance:
To Mask or Not?
To make the decision, people need to think about not only the numbers of vaccinated vs unvaccinated individuals in their community, but the local rates of disease, the experts said. And they need to know that the CDC guidance doesn't apply if regulations by federal or state authorities or businesses and workplace are in conflict.
Deciding on mask use sometimes depends on where you are going. What about going into grocery stores or large bin stores without a mask? "If you are fully vaccinated and have no other conditions that compromise your immune system and the rates of COVID are relatively low where you live and the vaccination rates are high, I would be 100% fine" without a mask, Marrazzo said. But it's important to think of all these factors in calculating your risk.
"I'm still wearing a mask when I go anywhere in public," she said, citing vaccination rates that have not yet reached 50% in her area.
If that rate reached 80%, the typical percentage talked about for herd immunity, and new cases were low, Marrazzo said she might shed the mask.
The CDC also continues to recommend masks on mass transit for all.
One population that also must be considered, and who must evaluate their risk, even if vaccinated, are the immunocompromised, Marrazzo said. While people think of the immunocompromised as those with HIV or organ transplants, the numbers are much larger.
"A study a couple of years ago indicated up to 3% of Americans may actually have been told by their physician they have some of level of being immunocompromised," she said. Among the examples are those who are on dialysis, on chemotherapy, or those taking any of the medications that modify the immune system.
"Millions of people fit this bill and we have literally little data on whether the vaccine works in them. We think it does," Marrazzo said.
Still, she said, it's a reason for these people to be cautious. For some other vaccines, the dose is modified for those who are immunocompromised. What's not known yet is whether additional doses of the COVID vaccines might boost protection for those who are immunocompromised.
Many people, even after vaccination, may choose to keep wearing a mask especially in indoor, crowded settings, Duchin said. "We need to expect, accept, and respect continued mask wearing by anyone at any time."
In most outdoor settings, he said, "I think masks are probably not necessary, vaccinated or not, regardless of age." One exception: close face-to-face contact, such as in certain sports.
How to Protect Toddlers and Infants
With masks not practical or recommended for infants and toddlers under 2 years old, Marrazzo said adults should remember that ''those very little kids don't do poorly at all [even if infected], although there is not a ton of data."
Adults should still treat young children as vulnerable, especially newborns. Adults not yet vaccinated should wear a mask when around them, she said.
J & J Vaccine Recipients
With less ''real world" data on the Johnson & Johnson vaccine, should those who got it think of themselves in a different risk group than those who got Moderna or Pfizer and adjust their behavior accordingly?
"The J&J vaccine, based on everything we know, does provide a great deal of protection," Marrazzo said. ''We don't know as much about prevention of transmission in the asymptomatic cases in the J&J."
Most of that data, she said, is from the mRNA vaccines Pfizer and Moderna. "I think it's an important area to study and learn about." But all three vaccines, overall, provide a high level of protection, she said.