Dr. David Geier  Robert F. Kennedy
Dr. David Geier and HHS Secretary Robert F. Kennedy
David Geier, long-time vaccine researcher, is helping rebuild access to CDC-linked datasets as critics question his credentials and past.

Health and Human Services Secretary Robert F. Kennedy Jr. announced that David Geier, a senior data analyst at the agency, is leading efforts to recover missing datasets from a federal vaccine safety system. The project involves the Vaccine Safety Datalink (VSD), a Centers for Disease Control and Prevention (CDC)-run program used for analyzing adverse effects of vaccines.

According to Kennedy's statement posted on social media platform X, Geier is working alongside other scientists to reassemble and depersonalize the so-called "lost" VSD data, which the CDC has acknowledged are missing or incomplete. Kennedy said the goal is to publish the data on a public-facing website to allow outside researchers access for replication and scrutiny.

"HHS has now contracted Geier to advise other scientists on how to find the 'lost' data and reaggregate the VSD datasets," Kennedy wrote. "All future HHS studies on vaccine safety and effectiveness will be replicable."

The CDC has not commented on the project or clarified which data are missing. The VSD, a collaboration between the CDC and 13 health care systems including six Kaiser Permanente groups, regularly informs peer-reviewed studies on vaccine safety. A recent publication using VSD data found no link between COVID-19 vaccination and miscarriage.

Geier's involvement has drawn sharp criticism. In a public letter, Sen. Maggie Hassan (D-N.H.) called him a "fraudster," alleging he lacks the qualifications to lead such a task. Hassan cited a 2012 Maryland case in which Geier was fined $10,000 for practicing medicine without a license at his late father's clinic. The Maryland State Board of Physicians pursued disciplinary action, which Geier later challenged in court.

While a lower court initially ruled in Geier's favor, awarding him damages on the grounds of agency overreach, an appeals court reversed that decision in part, citing legal immunity for state board members. The court did not dispute findings of possible malice in the board's conduct.

Despite the controversy, Geier has spent decades researching vaccine safety alongside his father, including several appearances before the Institute of Medicine — now the National Academy of Medicine. In 2005, the organization recommended broader access to VSD data, but Kennedy said the CDC has resisted outside examination.

"As a result of CDC's efforts, David Geier is the only living independent researcher to have had access to the VSD," Kennedy stated.

Geier's current role, listed in the HHS directory as a senior data analyst, has become a flashpoint in the broader debate over transparency in vaccine research. During a May congressional hearing, Kennedy defended Geier's hiring in the face of Sen. Hassan's public calls for his dismissal, citing what he described as "monkey business with the VSD, including allegations of fraud."

Kennedy emphasized that future studies will include mechanisms for third-party replication, ensuring public transparency and data accessibility. The HHS initiative marks a significant shift in vaccine safety oversight amid long-standing criticism that federal agencies have restricted access to underlying data.