The connection between vaccines and autism has been a persistent myth, one that has fueled vaccine hesitancy for decades despite the science, experts said.
With the COVID-19 pandemic in the rearview mirror and a new administration heading for the White House with prominent vaccine skeptic Robert F. Kennedy Jr. as President-elect Donald Trump's pick to lead the Department of Health and Human Services, vaccine hesitancy is on the rise in the Garden State.
The national debate around vaccines has been reignited by Trump's nomination of Kennedy, who has repeatedly claimed a link between vaccines and autism that New Jersey vaccine and autism researchers say is not supported by the evidence.
One New Jersey expert wants to stress the importance of education to combat the harmful myth, which has been spreading in recent years.
"We're seeing numbers not just for people refusing the COVID vaccine but also refusing measles, mumps and rubella, and routine childhood vaccines," said David J. Cennimo, an infectious disease specialist at Rutgers New Jersey Medical School. "That's become a significant concern because it can lead to newer outbreaks, and you're seeing it right now across the country with measles. Numbers are up, so we are seeing this, unfortunately, a lot."
The idea of vaccines causing autism originated with a 1998 study published in the medical journal Lancet by Andrew Wakefield, who linked the measles, mumps and rubella vaccine to autism. The study was retracted, and Wakefield was discredited. Since then, numerous large-scale studies, including a 2019 Danish study of over 650,000 children and a 2014 analysis of 1.2 million children, have found no connection between vaccines and autism.
"There is conclusively no link between vaccination and autism," said Cennimo. "The original study was erroneous, and subsequent research has consistently shown that vaccines are safe."
"There are many causes of autism," including genetic and environmental factors, according to Autism Speaks, a research and advocacy group for people on the autism spectrum. But, the organization adds on its website, "scientists have conducted extensive research over the last two decades to determine there is no link between childhood vaccinations and autism. The results of this research is clear: Vaccines do not cause autism. Additionally, vaccination can protect children from many preventable diseases like measles."
New Jersey has the third-highest rate of autism among 8-year-olds in the U.S., with 2.9% diagnosed in 2020, according to Centers for Disease Control and Prevention data coauthored by researchers with the New Jersey Autism Study at Rutgers. California leads with 4.5%, driven by early diagnosis efforts in San Diego, and Minnesota ranks second at 3%.
For years, New Jersey had the highest autism rate in the nation, though it has been overtaken in recent years by California and Minnesota.
Rates have been rising for much of the last quarter-century in the U.S., says Autism New Jersey, a nonprofit that represents the autism community. But the reason is still unclear, fueling suspicions about a range of potential causes, substantiated or not.
It's "difficult to ascertain is why ASD prevalence continues to climb," researchers with the New Jersey Autism Study at Rutgers wrote last year, referring to autism spectrum disorder. "While there are known risk factors for autism, including age of parents, multiple-gestation birth, prematurity, C-section delivery and care in the intensive care unit after delivery, these perinatal factors have remained relatively stable even as the rate of ASD has continued to surge."
Cennimo, who was not part of the research group, attributed the state's rate to its robust medical and educational systems, which excel at early diagnosis.
"New Jersey has excellent medical resources and school systems," he said. "This likely contributes to higher autism diagnosis rates. Our schools are particularly adept at recognizing children who are at risk or showing signs of autism. From a pediatric perspective, early intervention is crucial, because many children with autism can benefit significantly from timely support services. This creates a strong incentive to diagnose as early as possible."
But Walter Zahorodny, director of the New Jersey Autism Study, disputed the idea that increased awareness and medical services were largely responsible for the increase. The scope and breadth of increase has been extensive across all subtypes of autism spectrum disorder, from mild to severe, and across all demographic groups, said a Rutgers statement about his research.
"This is not just a phenomenon of becoming more sensitive to subtly impaired kids," he said.
While vaccine hesitancy has existed for decades, it has grown more widespread since the COVID-19 pandemic.
In 2018, New Jersey reported a rate of 71.5% of school-age children receiving recommended vaccinations. By 2020, the rate dropped to 68.7%, state data shows.
"We're seeing hesitancy not just for COVID vaccines but also for routine childhood vaccines like MMR," said Cennimo. "This hesitancy has broadened significantly and is becoming a major public health concern."
Cennimo expects vaccination rates to decline or stagnate until the resurgence of infections that were relegated to history.
"We will see measles again, and we'll see chickenpox," he said.
Declining vaccination rates pose real risks to public health. Herd immunity -- having enough vaccinated people to prevent the spread of disease -- requires about 95% coverage in a community for illnesses like measles.
In some areas of New Jersey, vaccination rates have dropped below this threshold, leaving communities vulnerable to outbreaks, Cennimo said. Measles, for instance, remains highly contagious and can lead to severe complications, including death.
Measles has a fatality rate of about 1 in 1,000 cases and can cause severe complications like encephalitis or pneumonia, the World Health Organization says.
"Vaccines are so effective that people don't see these diseases anymore," Cennimo said, calling trust in vaccines a "victim of success."
"Our grandparents remember the horrors of polio or whooping cough, but younger generations have no frame of reference. That's why public health education is so critical," he said.
Misinformation on social media plays a significant role in fueling skepticism.
"People trust what they see in their social networks, even if it's false," Cennimo said. "Social media magnifies fear and misinformation, making it harder to reach individuals with accurate, evidence-based information."
Politicization has also exacerbated the problem, framing vaccines as an infringement on personal freedoms, he said.
Cennimo, while avoiding overt political commentary, acknowledges concern within the medical community about Kennedy's nomination as health secretary.
"We have to see how policies unfold, but the focus must remain on evidence-based science to protect public health. Misleading information about vaccines puts lives at risk," Cennimo said.
In a recent interview, Trump considered the connection between vaccinations and rising autism rates and said he would put Kennedy on the task.
The path forward requires a multifaceted approach: combating misinformation, strengthening public health infrastructure in underserved places and fostering trust through education and transparency across the board, Cennimo said. He remains optimistic about New Jersey's ability to lead the way in addressing vaccine hesitancy while continuing to support people with autism.
"Public health is a collective responsibility," he said. "Vaccination decisions might seem personal, but their impact is shared by everyone in the community. It's up to all of us to prioritize science and protect one another."
Gene Myers covers disability and mental health for NorthJersey.com and the USA TODAY Network. For unlimited access to the most important news from your local community, please subscribe or activate your digital account today.