The Centers for Disease Control and Prevention's new guidance on indoor mask wearing may help some, but it's unlikely to make a huge difference, according to Dr. Ashish Jha, dean of Brown University’s School of Public Health.
The CDC announced Tuesday that it was recommending fully vaccinated people begin wearing masks indoors again in places with high COVID transmission rates, a reversal of previous guidance. The agency is also recommending that school children wear masks this fall, though the guidance is not a mandate, and decisions will be left to the state and local level.
Jha took to Twitter late Tuesday to talk about the new guidelines and what really needs to be done to improve the current situation.
"Changing guidance in response to new evidence isn't flip-flopping," he said. "It's what we should always do. CDC said in May that vaccinated people are largely safe (they rarely get infected, they don't spread). That was correct. At the time. Before Delta showed up."
But with infections up four times nationally over the past month, and even more in some areas of the U.S., he said the new CDC guidance is "reasonable" and will help, but only a little.
"So is this policy change based on data?" Jha said. Yes. Will it help a lot? Not really."
The only things that will make a big difference are reducing indoor gatherings, which is not really tenable or sustainable, and vaccinating more people, which is what he said needs to happen.