“Outside scientists” are asking the Centers for Disease Control and Prevention (CDC) to release the “new data” behind their announcement to revise mask mandates in areas that are hot spots for COVID-19 transmission.
The Washington Post reported on Thursday that Republican legislators and commentators noted that the CDC did not provide an explicit scientific rationale for reintroducing the indoor masking policy, despite the group’s director, Dr. Rochelle Walensky, citing “new data” in her press conference announcing the change.
Experts noted that the report only cites the “CDC COVID-19 Response Team, unpublished data, 2021,” as the agency’s justification for directing the public, even those who are fully vaccinated, to wear masks indoors if they are in a region where high rates of the delta variant of COVID-19 is prevalent.
The Post noted that the CDC justified its revised mandate by saying that “[p]eople who have had their shots and become infected with the delta variant of the coronavirus can harbor large amounts of virus just like unvaccinated people. That means they could become spreaders of the disease and should return to wearing masks indoors in certain situations, including when vulnerable people are present.”
But the CDC did not publish the new research and now “outside scientists” who spoke to the Post are curious.
“They’re making a claim that people with delta who are vaccinated and unvaccinated have similar levels of viral load, but nobody knows what that means,” Gregg Gonsalves, an associate professor at the Yale School of Public Health, told the outlet. “It’s meaningless unless we see the data.”
“When CDC Director Rochelle Walensky spoke to reporters Tuesday, she cited the ‘new scientific data’ but provided limited details about how the research was done,” the Post added. “She said the data comes from outbreak investigations in which researchers compared delta infections among vaccinated and unvaccinated people.”
A “federal official” told the outlet that the data will be “published immediately,” and said it was convincing enough that the CDC “saw the data and thought it was urgent enough to act,” even without publishing the information.
“Three senior administration officials who spoke on the condition of anonymity to describe internal discussions said the new research convinced health officials that it was time to update the agency’s guidance. When scientists compared viral loads in vaccinated and unvaccinated individuals infected with an earlier variant of the virus — the alpha variant, which was dominant in the spring — there were considerable differences in the amount of virus each carried,” the Post wrote.
It is unclear if the CDC is relying on peer-reviewed studies, or its own collected data, leaving many experts concerned.
The CDC’s updated guidance states that individuals should wear masks indoors if they are in areas hard-hit by the delta variant. It also states that individuals in a K-12 institutional setting should mask up, regardless of vaccination status.