The Centers for Disease Control and Prevention cited an unpublished study from India to justify its recommendation Tuesday that fully vaccinated people "wear a mask in public indoor settings in areas of substantial or high transmission" of COVID-19.
That study, which claimed the Delta variant produced an unusually large viral load in more than 100 vaccinated healthcare workers with "breakthrough infections," was listed as having failed peer review in the journal Nature when the CDC cited it.
Archives of the study's page on Research Square, a preprint server for unpublished research, show that it was marked "reject" on July 9 and remained so at least through the evening of July 26, Eastern Daylight Time.
The "reject" status and review notes were removed by mid-morning and replaced with "posted," suggesting Nature had approved the paper without revisions, which drew controversy on Twitter. The notes were quickly restored and status changed to "revise," bearing the same date — July 9 — as the original "reject" status.
Research Square addressed the confusion twice around noon Wednesday, blaming "a bug" and "a user interface error on our end." It said the paper was still under review "and the current editorial decision is 'Revise.'"
The review notes disappeared again from the "peer review timeline" later in the afternoon, leaving only a "current status" classification of the paper as "under review." Research Square also posted a revised header clarifying that the paper was being considered by "a Nature Portfolio Journal," not necessarily the flagship journal, and that it partners with the publisher on "a journal-integrated preprint deposition service."
The representations of Research Square would mean the CDC cited deficient research to back its finding that "emerging data suggest [COVID vaccines have] lower effectiveness against confirmed infection and symptomatic disease" caused by the Delta variant, which is "now predominant in the United States."
CDC Director Rachelle Walensky said fully vaccinated people "have just as much viral load as the unvaccinated, making it possible for them to spread the virus to others," which is why all children should wear masks in schools, NBC News reported. The White House announced it would start requiring masks in its buildings Wednesday.
Texas Republican Rep. Dan Crenshaw was among those calling out the CDC for the quality of research informing its policy decisions. "The 'game changer' data the CDC used for the mask mandate is from a single study from India," he tweeted. "The study was rejected in peer review. But CDC used it anyway."
Just the News contacted the CDC, Nature, Research Square and the study's authors to gain clarity on the chronology of the changes, the accuracy of the review notes, and the timing of any conversations among the U.S. agency, London-based publisher and researchers in the U.K. and India. None responded.
The research team submitted the paper to Nature June 18, and it was assigned an editor and distributed for peer review the same day, according to the original "peer review timeline" on Research Square.
The four reviewers turned in their assessments between June 20 and July 8. The day after the last came in, the editorial decision purportedly arrived from Nature: "Reject after peer review."
But the preprint study was already making waves before review was finished. Science News reported July 2 that "antibodies from both recovered and vaccinated people were less potent at stopping delta from infecting cells than alpha or the original version of the virus from Wuhan, China." The Indian healthcare workers had been given an AstraZeneca vaccine, which was not approved for use in the U.S.
Lead author Ravindra Gupta, a virologist at the Cambridge Institute of Therapeutic Immunology & Infectious Disease, told the publication that the Delta variant was not a serious threat to younger and healthier vaccinated people. But this strain is sending vaccinated people who are older and have underlying conditions to the hospital, and "we will see deaths."
Nature itself was more circumspect in a report Tuesday on the effect of vaccines on different COVID strains, claiming there was no "published data" on the Delta variant. It cited mid-July preprints from Israel and China but conspicuously left out the earlier India research.
"Studies from India with vaccines not authorized for use in the United States have noted relatively high viral loads and larger cluster sizes associated with infections with Delta, regardless of vaccination status," the CDC said in the "breakthrough infections" section of its updated science brief, citing Gupta's research.
"These early data suggest that breakthrough Delta infections are transmissible," which is consistent with unpublished data, the agency said. The brief specifies that it "synthesizes the scientific evidence supporting CDC's guidance for fully vaccinated people," which was updated the same day.
The CDC didn't stop at recommending masks in public indoor settings regardless of vaccination.
In light of the Delta variant, "fully vaccinated people might choose to wear a mask regardless of the level of transmission, particularly if they are immunocompromised or at increased risk for severe disease from COVID-19," or if anyone in their household is not vaccinated.
Even fully vaccinated people with a "known exposure to someone with suspected" COVID-19 should be tested within a few days of exposure and wear a mask indoors for two weeks or until they get a negative test result, the agency said.