The Centers for Disease Control and Prevention announced updated guidance on Tuesday which states that people living in areas with high COVID-19 transmission rates (which is a significant portion of the United States) should once again wear masks in indoor public settings, regardless of whether they've been vaccinated. 

The agency has faced criticism throughout the day for a variety of reasons, including the fact that some experts think the latest messaging is off-base when it comes to the cause of the latest wave of infections. For instance, Dr. Jonathan Reiner, a medical analyst for CNN, took issue with the CDC Director Rochelle Walensky's emphasis on the finding that "in rare occassions some vaccinated people infected with the Delta variant after vaccination may be contagious and spread the virus to others." Walensky said that "this new science is worrisome and unfortunately warrants an update to our recommendation."

But Reiner thinks the CDC is downplaying the real issue the U.S. is facing: the high number of unvaccinated adults. In other words, he's arguing the messaging should be centered around the need to get more people inoculated against the virus.

While Walensky flagged those reportedly rare instances of transmission, she did also make a call for an increase in vaccination rates, especially because she's concerned about the emergence of new mutations that could evade vaccines in their current form.