WASHINGTON | A Senate investigation has produced what may be the most significant domestic health transparency reckoning since the COVID-19 pandemic began. Senator Ron Johnson, Republican of Wisconsin and Chairman of the Permanent Subcommittee on Investigations, has released nearly 2,600 pages of internal government documents showing that Biden administration health officials were aware of serious COVID-19 vaccine safety signals as early as 2021, chose not to immediately warn the public, and in at least one case, actively discouraged a senior FDA scientist from using a more accurate method to detect those signals.
The hearing, held on April 29 and titled “Unmasked: How Biden Health Officials Purposely Turned a Blind Eye Toward COVID-19 Vaccine Safety Signals,” has drawn significant attention from health freedom advocates, independent journalists, and members of Congress on both sides who have called for accountability in pandemic-era public health decisions.
Here is what the documents actually show.
The Whistleblower at the Center of It All
The most striking figure in Johnson’s investigation is Dr. Ana Szarfman, a senior medical officer and safety data mining developer at the FDA who helped build the agency’s own adverse event detection system.
Within three months of the vaccines being rolled out, in March 2021, red flags were appearing in weekly data dumps from doctors and patients reporting health problems after the shots. When Dr. Szarfman, whose job was to monitor vaccine data for warning signs, repeatedly raised the alarm throughout 2021, she was ignored. Internal emails show her colleagues tried to stop her from using a newer, more accurate statistical methodology to investigate the data.
Szarfman used an updated data analysis technique that identified dozens of statistically significant safety signals for adverse events associated with the COVID-19 vaccines, and immediately shared her findings with other FDA officials responsible for COVID-19 vaccine safety surveillance.
According to Johnson’s report, rather than investigating her findings, senior FDA officials including Dr. Peter Marks, who led the FDA’s Center for Biologics Evaluation, were made aware and no formal action was taken. Dr. Szarfman’s more advanced method was not adopted. The older system, with its known limitations, remained in use.
What the Older System Was Hiding
The core technical issue at the heart of the investigation is a method called Empirical Bayesian data mining, which Johnson’s documents show Biden health officials acknowledged had significant statistical limitations in their ability to detect safety signals.
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Biden health officials continued to employ their older data mining method with known limitations that prevented the FDA from detecting adverse events, despite being aware in early 2021 of a newer state-of-the-art method that could better detect statistically significant safety signals.
The doctors advocating for the updated system uncovered approximately 25 statistically significant safety signals for adverse events associated with the COVID-19 vaccines that were not previously detected by the FDA’s current methodology. These included sudden cardiac death, Bell’s palsy, and pulmonary infarction.
To be clear: these are safety signals, meaning statistical patterns that warranted investigation, not confirmed proof that the vaccine caused each condition. But the question Johnson’s investigation raises is not whether every signal was real. It is whether the public was entitled to know these signals existed while they were being asked to take the vaccine and boosters.
The Stroke Cover-Up
Beyond the Szarfman case, Johnson’s March 2026 letter to HHS Secretary Robert F. Kennedy Jr. laid out a separate and specific instance involving ischemic stroke.
As early as November 2022, vaccine safety surveillance systems run by Biden health officials began detecting statistically significant safety signals for ischemic stroke among individuals aged 65 and older following receipt of the Pfizer-BioNTech COVID-19 bivalent booster. Rather than immediately issue a formal warning to the public, documents show that in December 2022, the Biden White House and HHS pushed to increase uptake of the booster for people 65 years and older.
Johnson released a January 2023 internal HHS communications plan that shows Biden officials editing the messaging around the stroke signal to downplay its significance, according to documents on his Senate website. The full extent of HHS’s awareness of that signal remains under investigation, with Johnson noting that key records are still missing.
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What the Biden White House Did in December 2022
The timeline here matters. In November 2022, internal surveillance systems flag a stroke signal in older adults taking the Pfizer bivalent booster. In December 2022, rather than issuing a warning, the White House and HHS coordinate a push to increase booster uptake in that same demographic. In January 2023, communications staff edit internal documents to soften the language around the stroke signal.
It was not until January 13, 2023, that the FDA and CDC issued a public safety communication acknowledging the signal, framed as something the agencies were monitoring. By that point, the booster push had already run its course.
What Johnson Is Calling For
Johnson called the conduct a grotesque abuse of power, stating that people died and were permanently disabled because they were denied fully informed consent on the COVID injections.
Johnson has sent the investigation findings to RFK Jr. at HHS and is requesting additional records. He has also raised the possibility of criminal accountability, though no charges have been filed or formally recommended at this stage. His investigation is ongoing.
The nearly 2,600 pages of documents released across his two major document drops are publicly available on his Senate website for anyone to review.
What the Other Side Says
Johnson is a polarising figure and his investigation has drawn predictable pushback. Critics argue that safety signals in the VAERS system are not the same as confirmed harms, that the older detection methodology was validated at the time, and that the communications edits reflected standard public health messaging strategy rather than a deliberate cover-up.
The Fulcrum, which covered the hearing, noted that the subcommittee hearing included allegations that FDA officials failed to adequately gather and analyze data on vaccine adverse effects, but also reported that several public health experts dispute the framing that the signal suppression amounted to intentional concealment.
None of the Biden-era officials named in the documents have publicly responded in detail to the specific allegations in Johnson’s report at the time of publication.
Why This Connects to the Pfizer Document Debate
If you have been following our coverage of the Pfizer 5.3.6 document that lists hantavirus among 1,233 monitored conditions, Johnson’s investigation adds important context. The Pfizer document showed what regulators agreed to watch for. Johnson’s investigation shows what happened when a government scientist actually detected signals within that surveillance system and tried to act on them.
Read our full breakdown here: Pfizer Document Lists Hantavirus Among 1,233 Monitored Conditions
Together, the two stories paint a more complete picture of the post-authorization safety landscape. The monitoring framework existed. The signals were detected. And according to Johnson’s documents, the response to those signals was to manage the messaging rather than inform the public.
Whether that constitutes a deliberate cover-up or a series of institutional failures is now a matter of active congressional investigation. The documents are public. Americans can read them and decide.
What Comes Next
Johnson has stated the investigation is not finished. More records have been requested from HHS. The question of whether any Biden-era officials will face formal accountability, through congressional referral, inspector general review, or other mechanisms, remains open.
Briefly USA will continue reporting on this story as it develops.
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