The CDC intends to award a no-bid contract to Rensselaer Polytechnic Institute (RPI) to examine the association between vaccinations and autism prevalence, despite widespread evidence showing no link between the two. 

The move, made public September 11, sparked concern among autism experts who questioned the need for additional research on an issue widely consider settled. 

“Dozens of studies with millions and millions of kids have demonstrated neither the vaccines themselves, the timing of the vaccines, nor how many we give are associated with autism,” David S. Mandell, ScD, a member of the Coalition of Autism Scientists executive committee and professor of psychiatry and director of the Center for Mental Health at the University of Pennsylvania Perelman School of Medicine in Philadelphia, told Medscape Medical News. 

The news of the contract comes shortly before the expected release of a report on the causes of autism, which was commissioned earlier this year by US Health and Human Services Secretary Robert F. Kennedy Jr, a longtime vaccine critic. 

Sole-Source Contract Questioned

Although the agency’s plans to study vaccines and autism risk were first reported in March, the announcement of a sole-source contract to RPI raised eyebrows since government contracts are usually competitive unless the awarding agency can demonstrate that a service can only be provided by a single source.

In the notice of intent announcement, the CDC cited RPI’s “unique ability to link children to maternal cohorts using proprietary databases and de-identified data sets, enabling advanced statistical analyses within the project’s timeframe.” 

RPI is a well-known and reputable university “so that part was not concerning for me,” Mandell said. However, many institutions nationwide can conduct this kind of research, so the claim that RPI has a unique ability to do so gave him pause, Mandell added.

A spokesperson for RPI told Medscape Medical News that the project would be led by Juergen Hahn, PhD, director of the RPI Jackson Center for Biotechnology and Interdisciplinary Studies, Troy, New York. Hahn did not respond to requests for comment. 

RPI “is aware of and appreciates the Center for Disease Control’s intent to award the grant,” the spokesperson stated. “Professor Juergen Hahn is a biomedical engineer and data science expert who has conducted extensive research focused on autism risk factors. He is renowned for the quality and rigor of his research. If this project is awarded, he intends to publish the results of his work at the conclusion of the project.”

Mandell said Hahn had done interesting work in autism. However, he added, “there is nothing in his portfolio or his publications that would suggest that he has the whole skill set, or the team he is putting together has the full skill set, to do the kind of analysis you need to answer these complicated questions.”

‘Settled Science’

Following publication of a 2012 Institute of Medicine report, a 2013 CDC study, and a highly-cited 2014 meta-analysis, the CDC has generally indicated that the autism-vaccine link is “settled science,” Zachary J. Williams, MD, PhD, resident physician in psychiatry, research track, at UCLA Semel Institute for Neuroscience and Human Behavior in Los Angeles, told Medscape Medical News. 

“In fact, the CDC website discussing autism and vaccines, which has not been updated since late 2024, still very much gives this impression to readers,” added Williams, who is also a fellow and advisory board member of the Frist Center for Autism and Innovation at Vanderbilt University School of Engineering in Nashville and co-founder and administrator of Autism PROMnet, a group formed to promote valid and meaningful outcome measurement in autism research and clinical practice. 

“By ‘unsettling’ the science on this topic, the CDC is in essence legitimizing the possibility that the narrative on autism and vaccines could be wrong,” added Williams, who has autism himself. 

“The decision to fund yet another study on the association between autism and vaccines appears largely driven by Secretary Kennedy’s personal — and extremely heterodox — beliefs about autism causality and vaccine safety,” he added.

Limitations of Observational Research 

Because conducting randomized trials of vaccines with proven efficacy would be unethical, Mandell said, it’s likely Hahn and any colleagues will rely on observational data. Potential limitations with these studies include multiple confounders that could skew results and an inability to show causation even if an association is found.

No matter the results, “we’ve already seen all it takes is leadership within the government raising the question about vaccinations to reduce the rates at which kids get vaccinated,” Mandell said.

Williams agreed. 

“Combined with the new wave of vaccine-hesitancy we saw during COVID, I fully expect this work to further drive down vaccination rates among the American public,” he said.

“In the same way that Andrew Wakefield’s ‘vaccines cause autism’ claim manages to live on long after his paper was found to be fraudulent and retracted, there is a clear possibility of permanent damage to the public’s trust in vaccines as a vehicle for disease prevention,” Williams added. 

The notice of intent announced last week comes with a 15-day waiting period, after which the CDC could finalize the contract.

Mandell reported no relevant financial relationships. Williams previously received consulting fees from Roche on projects related to autism, specifically making clinical trials more participant-friendly and developing novel outcome measures.