CDC did not say vaccines are failing or vaccinated people are superspreaders

Call it the domino effect: First, the Centers for Disease Control and Prevention changed its mask-wearing recommendations for vaccinated people. Next, a leaked report from the agency suggested that COVID-19 might be transmitted by vaccinated people as easily as the unvaccinated.

Then, misinformation began to spread on social media. 

"CDC confesses: Vaccines are failing, and the vaxxed can be superspreaders," read one viral Instagram post. It was a screenshot of Natural News, an anti-vaccine website that has promoted conspiracy theories. 

The post continued, "Via the words of the CDC’s own director Dr. Rochelle Walensky, vaccines are now failing, and vaccinated people may now carry higher viral loads than unvaccinated people, contributing to the spread of COVID." 

The post was flagged as part of Facebook’s efforts to combat false news and misinformation on its News Feed. (Read more about our partnership with Facebook.)

We could not find any evidence — published or broadcast interviews, or CDC news releases  — to support the claim that Walenksy said vaccines are failing. And she did not say vaccinated people carry "higher" viral loads than unvaccinated people. She said vaccinated and unvaccinated people have "similarly high" viral loads.

The CDC released updated guidance on July 27 for vaccinated people, recommending they wear masks indoors in geographic areas that have "substantial and high transmission" of COVID-19. On that date, 46% of U.S. counties had high transmission and 17% had substantial transmission, CNN reported. 

Walensky said the changes were needed because the agency had new scientific data showing that the delta variant behaves differently from past strains of the virus. The agency did not immediately release the data being referenced, though.

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A few days later, news organizations published a leaked internal report from the CDC that suggested that vaccinated people who have breakthrough infections from the delta variant might be able to transmit COVID-19 as easily as the unvaccinated, and also have viral loads similar to the unvaccinated who are infected with the variant. 

Viral load is "a measure of the density of viral particles in the body," according to the journal Nature. Walensky said higher viral loads "suggest an increased risk of transmission and raised concern that, unlike with other variants, vaccinated people infected with delta can transmit the virus." 

The finding was based in part on a cluster infection on Cape Cod in Massachusetts that so far has been associated with 900 COVID-19 cases, most of which are from the delta variant. About three-quarters of those infected had been vaccinated. Though the total number of cases was high, serious cases were rare: there were seven hospitalizations and zero deaths. 

The internal CDC document noted that breakthrough cases continue to be rare and a small percentage of cases.

NBC News collected data from 38 states and found 125,682 breakthrough cases, representing less than .08 percent of those who have been fully vaccinated, or one in 1,300. Kaiser Family Foundation also analyzed breakthrough cases from 25 states that report data on them and found that in more than 9 in 10 COVID-19 cases, hospitalizations and deaths have been among the unvaccinated or not yet fully vaccinated. 

An Instagram post said, "CDC confesses: Vaccines are failing, and the vaxxed can be superspreaders." The post said this was "via the words of the CDC’s own director Dr. Rochelle Walensky."

We could not identify any instance in published or broadcast accounts, or CDC news releases, where Walensky said vaccines are failing. And she did not say vaccinated people are superspreaders; she said vaccinated people infected with the delta variant have similarly high viral loads as unvaccinated people. 

We rate this claim False.