WASHINGTON — On Friday, U.S. Sen. Ron Johnson (R-Wis.), sent a letter to Director of Centers for Disease Control and Prevention (CDC) Dr. Rochelle P. Walensky, demanding all information and data the CDC used to create its leaked slide deck titled, “Improving communications around vaccine breakthrough and vaccine effectiveness.”  On Thursday, the Washington Post published leaked CDC slides relating to vaccine effectiveness and the Delta variant, but it is unclear whether this information or the underlying data were ever produced to Congress.

“Unfortunately, this leaked slide deck provides only minimal insights into what CDC allegedly knows about the effectiveness of vaccines against the Delta and other variants of the SARS-CoV-2 virus,” the senator wrote.  “It is also not clear whether CDC shared this information with Congress before it was leaked to the press.  In order to ensure the American people are fully informed about the effectiveness of the vaccines and the risks of the Delta and other SARS-CoV-2 variants, please provide the following information:

“1. All data and studies used by CDC to create the slide deck titled, ‘Improving communications around vaccine breakthrough and vaccine effectiveness’ including but not limited to all of the data cited in the slides; and

“2. All documents and data referring or relating to breakthrough cases and vaccine effectiveness.” 

A copy of the letter can be found here and below.

July 30, 2021

Rochelle P. Walensky, MD, MPH

Director

Centers for Disease Control and Prevention

Dear Director Walensky:

                On July 29, 2021, the Washington Post reported on a leaked Centers for Disease Control and Prevention (CDC) slide deck titled, “Improving communications around vaccine breakthrough and vaccine effectiveness.”[1]  The slides appear to present information and data that the CDC has collected related to vaccine effectiveness and the Delta variant of the SARS-CoV-2 virus.[2]  I write to request information and data related to this slide deck.

                According to the slides, CDC stated that vaccines are “less effective at preventing infection or transmission” against the Delta variant of the virus.[3]  For example, one slide comparing the effectiveness of the Pfizer 2-dose vaccine regimen against the Alpha and Delta variants seems to indicate the vaccine may be only 64 percent effective in stopping infection by the Delta variant.[4]  Further, another slide stated that “breakthrough infections [of the Delta variant] may be as transmissible as unvaccinated cases,” calling into question the overall effectiveness of the vaccines in limiting the spread of COVID-19.[5]

                Unfortunately, this leaked slide deck provides only minimal insights into what CDC allegedly knows about the effectiveness of vaccines against the Delta and other variants of the SARS-CoV-2 virus.  It is also not clear whether CDC shared this information with Congress before it was leaked to the press.  In order to ensure the American people are fully informed about the effectiveness of the vaccines and the risks of the Delta and other SARS-CoV-2 variants, please provide the following information:

1. All data and studies used by CDC to create the slide deck titled, “Improving communications around vaccine breakthrough and vaccine effectiveness” including but not limited to all of the data cited in the slides; and
2. All documents and data referring or relating to breakthrough cases and vaccine effectiveness.

In addition, I request that you provide a briefing to my staff on the information contained in CDC’s slide deck.  Please provide the requested information and briefing by no later than August 13, 2021 at 5:00 pm.

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