Thorsen vaccine fraud plea doesn't sink the MMR study

An anti-vaccine narrative gaining steam online this week treats a Danish researcher's guilty plea as the collapse of a landmark vaccine study. The Thorsen vaccine fraud case is real. Poul Thorsen, 65, a former visiting scientist at the U.S. Centers for Disease Control and Prevention, admitted in federal court to stealing research grant money. Federal prosecutors say the fraud concerned the grant money. A Reuters fact check published this week adds that the plea agreement contains no charges tied to the research itself.

On Sept. 1, prosecutors announced that Thorsen pleaded guilty to one count of wire fraud for a scheme that ran from February 2004 through June 2008 and diverted more than $1 million in research funds granted to Danish institutions. In a statement, the U.S. Attorney's Office said the money was supposed to support studies on autism, cerebral palsy and fetal development, and that Thorsen redirected it to himself through forged paperwork.

The case is older than the plea. A federal warrant was issued in 2011, and Thorsen stayed outside the United States for nearly fourteen years. He was arrested in Germany in June 2025 and extradited to the U.S. in May 2026. Prosecutors said he had been the principal investigator for more than eleven million dollars in CDC grants awarded to two Danish agencies between 2000 and 2009, covering autism and vaccine exposure, cerebral palsy and prenatal infection, and fetal alcohol exposure.

Disability Scoop reported the mechanics of the scheme this month. Between 2004 and 2008, prosecutors said, Thorsen submitted fraudulent invoices carrying the forged signature of a CDC laboratory section chief to Danish authorities, a university and a hospital involved in the research. Aarhus University transferred hundreds of thousands of dollars into accounts it believed belonged to the CDC that were actually controlled by Thorsen. He spent the money on a house in Atlanta, a Harley-Davidson motorcycle, cars, credit card payments and cash withdrawals.

The posts jump from the money to the science

The guilty plea quickly became a talking point in vaccine-skeptic corners of the internet. A Sept. 3 Instagram post declared that "the man behind one of the most cited vaccine safety studies in history just pleaded guilty to fraud," and claimed Thorsen had run the CDC-funded study that was used for more than two decades to dismiss parents who questioned vaccines. Comments under an X post resurfacing news reports about the case linked the financial fraud directly to the study itself, with one commenter writing that Thorsen had a financial reason to say vaccines do not cause autism.

The leap is what fact-checkers are pushing back on. Thorsen co-authored a 2002 paper in the New England Journal of Medicine, "A Population-Based Study of Measles, Mumps, and Rubella Vaccination and Autism," which reported no association between the MMR vaccine and autism in a Danish cohort. He also co-authored a 2003 paper in Pediatrics on thimerosal-containing vaccines. Eight researchers wrote the 2002 paper, and the lead author, Kreesten Madsen, told Reuters that Thorsen's main contribution was connecting the team with the CDC, that he had no access to the study data, and that Madsen stood behind the data, the analyses and the published findings.

Madsen stressed that he carried out the data acquisition and the initial analyses independently of Thorsen, according to Reuters. The Thorsen vaccine fraud case has also drawn remarks from podcast host Joe Rogan, which circulated as a widely shared image in September, Reuters reported. A representative for Rogan did not respond to a request for comment, and the CDC did not respond either. The episode follows the pattern of conspiracy rumors that outrun their corrections, where a real document or event becomes raw material for claims far beyond what it shows.

The plea says nothing about the research

Reuters gave the viral claims its "missing context" verdict. The indictment and the plea agreement cover wire fraud tied to grant money, and neither contains fraud charges or criminal charges tied to his scientific research. The wire fraud charge was about stealing grant money from the CDC, not about faking data. Separately, multiple scientific studies have found no link between MMR vaccines and autism, so the consensus never rested on the 2002 paper alone. The New England Journal of Medicine did not respond to a request for comment, and Thorsen's legal representative did not respond either. Thorsen is scheduled for sentencing in December.