The CDC's mask guidance change, explained

The CDC backtracked its stance on vaccinated people not needing to wear a mask in certain situations, following rising COVID-19 infections and the rapid spread of the delta variant.

Tuesday, the director of the Centers for Disease Control and Prevention Dr. Rochelle Walensky said vaccinated people are highly recommended to mask up in public indoor settings in high transmission areas and explained why in a phone call with news reporters.

"But unlike the alpha variant that we had back in May where we didn't believe that if you were vaccinated you could transmit further, this is different now with a delta variant," said Walensky. "We're seeing now that it's actually possible if you are a rare breakthrough infection that you can transmit further, which is the reason for the change.

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USF Health virologist Dr. Michael Teng said sometimes it's necessary to change health recommendations, but explaining the change to the public is crucial.

"Conditions on the ground are changing and they change often, right? So we are now seeing an increase in cases. Again, I think it behooves our public health officials to be flexible. You have to change with the time," said Teng.

The country is entering a fourth wave, and some public health experts said the CDC’s switch comes a bit late.

"This is the right thing to do. It would have been the right thing to do a couple of weeks ago. So, they're a little bit slow, but I really think the thing that I would say is that to make sure that people understand the vaccines are working," Teng said.

Data shows the vaccines are effective at protecting you from ending up in the hospital or dying even as the virus mutated into nastier strains. But as of July 27, the CDC reported only 49% of the country as fully vaccinated and 56% with at least one dose. Dr. Teng shares what the CDC changes could do to public confidence.

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"So, you know, I think explaining why they do things a little bit better than they have been doing would go a long way to retain some confidence," said Teng. "At least for me, the way that you inspire confidence is through transparency. Tell us why we're doing this rather than just saying, ‘Oh, we're going we're doing this and then now we're doing that.’" 

Doctors said unvaccinated people are fueling the spread right now and are also the ones mainly going into the hospital. Changing masking recommendations can help people understand just how contagious the virus can be, scientists said.

Public health experts said they hope businesses also take another look at their mask policies to help stop the spread, especially since many children can’t currently get the vaccine. They said they hope it will encourage more people to get the shot.