Senate Probe: Biden FDA, CDC Knew of Pfizer Bivalent Booster Stroke Risk in Seniors, Kept Public in Dark

A Senate investigation alleges that federal health officials under the Biden administration identified a significant stroke risk linked to Pfizer's COVID-19 bivalent booster for seniors in late 2022—and deliberately withheld that information from the American public. According to a formal letter from Senator Ron Johnson (R-WI), chairman of the Senate's Permanent Subcommittee on Investigations, a review of roughly 2,000 pages of federal records reveals that officials at the FDA and CDC were aware of the potential safety signal for months without issuing any public warning.

The evidence centers on a potential connection between the Pfizer-BioNTech bivalent booster and ischemic stroke, a blockage of blood flow to the brain, in individuals over 65. Senator Johnson's letter to HHS Secretary Xavier Becerra cites internal records showing that, as early as October 2022, officials had identified this concern. Crucially, the investigation found that between November 2022 and March 2023, seven separate analyses of incoming safety data repeatedly flagged the same elevated risk, indicating a persistent internal alert that never translated into public communication.

The allegations, if substantiated, point to a profound failure in the government's duty to ensure transparent vaccine safety monitoring. The core tension lies not in the existence of a rare adverse event—which is a known aspect of mass vaccination—but in the alleged decision by regulatory bodies to withhold a known, specific risk from the very population most vulnerable to it. This places the Biden administration's FDA and CDC under intense scrutiny for potentially prioritizing policy continuity over informed public consent, a breach that could severely damage institutional trust in future public health emergencies.