Dr. Scott Gottlieb: New CDC mask guidance is 'confusing,' will have 'negligible impact' on Delta surge

Dr. Scott Gottlieb, former Food and Drug Administration commissioner, said Wednesday that he thinks the Centers for Disease Control and Prevention's new guidance recommending that vaccinated people wear masks will have a "negligible" effect on reducing COVID spread.

"I don't think things have shifted, I think they've gotten more confusing for the average consumer because of the shifting advice from CDC," Gottlieb said during an interview on CNBC News.

The CDC issued new guidance Tuesday recommending that vaccinated people wear masks indoors in public if they are in an area with substantial or high transmission of COVID-19. Increased COVID-19 cases among the unvaccinated caused by the highly transmissible Delta variant and instances of breakthrough infections motivated the CDC to insist that people mask up again, including everyone in K-12 schools, in order to reduce viral spread.

"The bottom line is ... the vaccine doesn't make you impervious to infection. There are some people who are developing mild and asymptomatic infections even after vaccination," explained Gottlieb, who sits on the board of Pfizer. He said those who live in a "high prevalence area" should be aware that even if they are vaccinated a transmissible strain like the Delta variant could spread to elderly people or children who are vulnerable to infection, especially if they are unvaccinated.

But he doesn't think that risk requires widespread masking for everyone in America who's been vaccinated.

"Whether or not that should then translate into general guidance for the entire population that if you're vaccinated you should wear a mask, I don't think that that's the case," he said. "I don't think we're going to get enough bang for our buck by telling vaccinated people they have to wear masks at all times to make it worth our while."

The reason new guidance isn't worthwhile, according to Gottlieb, is that it appears the surge in COVID-19 cases caused by the Delta variant is nearing a peak. He predicted that in "another two or three weeks" the surge of COVID-19 cases will begin to subside.

"This new guidance will have a negligible impact on that," he said.

Instead of telling all vaccinated people to wear masks indoors, Gottlieb says the CDC should tell people who live in areas at high risk of COVID spread that if they experience symptoms of COVID or come into contact with someone who has it, they should get tested and consider wearing a mask.

People should also be aware that not all masks offer equal protection from contracting the virus or from spreading it.

"The physical properties of the virus as best we know haven't changed. The reason why this Delta strain is more transmissible is because there's just more of it, you develop more virus early in the course of your infection," Gottlieb said.

"If you as an individual want to protect yourself from this virus, mask quality does matter. Wearing a higher quality N95 or KN05 mask is going to afford you more protection. In the setting of a more transmissible strain, you need to be mindful of the quality of the mask that you're wearing."

Wearing a cloth mask or procedure mask will decrease the likelihood of spreading the virus to others, Gottlieb added, but is unlikely to offer protection from other people around you.