It’s challenging to report on an illness such as autism, which scientists and doctors are only beginning to understand (the disease was described in the 1940s) and over which there is so much debate.

There is even disagreement around the question of whether or not there has been a real increase in the number of children being diagnosed with autism in California. In our TV segment, we interview psychologist Ron Huff, director of clinical services at the Alta California Regional Center in Sacramento. In the mid-1990s, Huff sounded the alarm about an increase in the number of reported cases of autism in California. (Through California’s 21 regional centers the state’s Department of Developmental Services offers services to children and adults with developmental disabilities).

“In 1996 I asked the Department of Developmental Services to pull some raw data off of their statewide electronic information system. And when I saw that data it was obvious that there were a lot more kids in our system with autism than anyone else had expected,”Huff told QUEST. “By 1999 the (California) legislature decided to have the department do a formal study of the number of people who were entering the system with autism. So we looked at about 11 years of data and recognized that there was a 300 plus percent increase in the number of kids coming in with autism.”

Since then, researchers have vigorously been debating whether or not there is a true increase in the number of cases. Huff believes that at least part of the increase is a true increase, in other words, that not all of the increase can be explained by factors such as more accurate diagnosis of autism, increased awareness or better availability of services. But other researchers like Kaiser Permanente epidemiologist Lisa Croen feel there isn’t enough information to conclude that even part of the cases are due to a true increase.

“Unfortunately, I don’t think we really have the data, and no one really has the data right now to answer that question adequately,” she told QUEST. But in her view, whether or not there’s a true increase, there is indeed a crisis afoot. “It goes without question that there are definitely more people being diagnosed with autism today than ever before and that is a really big public health crisis. Estimates across the country are that one in 150 children at about 8 years of age will have a diagnosis of autism. So whether or not the increase, or how much of this increase, is really due to a true increase in occurrence, the question now is what’s causing this and what are the risk factors and that’s what we really have to concentrate on.”

The research looking into factors other than genes is just beginning. The Centers for Disease Control have launched a large epidemiological study called SEED that seeks to answer the question of what the environmental causes of autism are. When researchers talk about “environmental factors” they mean this very broadly. These factors include, for example, the age of the parents. For our TV story we filmed Meghan Wallace, a four-year-old with an autism diagnosis who is participating in SEED. In Northern California, Kaiser Permanente is overseeing the research. Both children with and without autism are being enrolled. “There really has never been a large, robust, well-designed epidemiologic study that can adequately study the many possible risk factors for autism spectrum disorders,” said Lisa Croen, who is one of the principal investigators on SEED.

At the same time, U.C. Davis’ M.I.N.D. Institute is carrying out a smaller study into the causes of autism. It’s called MARBLES and it’s funded by the EPA and the National Institute of Environmental Health Sciences. By studying pregnant women, MARBLES principal investigator Irva Hertz-Picciotto hopes to find out if there are any risk factors for autism that happen during pregnancy. In our TV story, we followed M.I.N.D. Institute personnel as they visited one of the families in the study. They had followed the mother through her pregnancy and delivery and were now taking samples from her six-month-old boy. The researchers collected everything from his dirty diapers to dust from the family’s rug. In between, they asked the mom about her family’s use of pesticides and cleaning products.

Hertz-Picciotto’s research stemming from another M.I.N.D. Institute study has already pointed to a connection between autism and pesticides. In May of 2008, she and her colleagues reported at the International Meeting for Autism Research in London that mothers of autistic children were twice as likely as mothers of children who didn’t develop autism to report that they had used household insecticides and pet shampoos for fleas or ticks. They reported using these products during a period between three months before conception and the first year of the child’s life. Other risk factors are also starting to emerge. A study by Lisa Croen and colleagues reported that paternal and maternal age are risk factors for autism. “What we found was for every 10 years of increase in the age of a mother or a father, the risk of autism went up by about 20 or 30%,” Croen told QUEST.

Both the SEED and the MARBLES studies are looking at the question of whether or not childhood vaccination is a risk factor for autism. This is another issue that we talk about in our TV story. Concerned about guaranteeing that infectious diseases don’t reemerge, public health officials at agencies like the CDCs state that research doesn’t bear out an autism-vaccine connection. But UC Davis’ M.I.N.D. Institute is taking a more nuanced approach to the question. Based on new findings by their researchers showing that the immune systems of autistic children are different than those of typically developing children, the Institute suggests that a small number of children may respond to vaccines in an atypical way. They quickly add that there isn’t yet a way to determine who those children might be. Studies like SEED and MARBLES might help elucidate this and other questions about what remains a mysterious disease.

Producer’s Notes: Autism: Searching for Causes 12 March,2016Gabriela Quirós
  • Matt

    Your statement
    “Based on new findings by their researchers showing that the immune systems of autistic children are different than those of typically developing children, the Institute suggests that a small number of children may respond to vaccines in an atypical way.”

    includes a link to a MIND institute page. As part of the evidence for the idea that some people may respond differently to vaccines, they include the study on mice by Dr. Hornig. Included in the webpage is the statement, “These findings will, of course, need to be independently replicated.”

    MIND Institute researchers tried to replicate those results, even using 10 times the thimerosal exposure as did Dr. Hornig. That attempt at replication failed–there were no behavioral or physical changes noted in the study by Berman et al.

    The MIND Institute should update that page, and make statements based on the current understanding rather than this older data.

  • Gabriela Quiros

    Hi Matt,

    Thank you for your post. When I say in my post that there is new research showing that the immune system of children with autism is different than the immune system of typically developing children I am referencing a 2008 paper titled “Gene expression changes in children with autism,” by Jeffrey P. Gregg and others.

    The authors of this study, who are affiliated with UC Davis’ M.I.N.D. Institute and Kaiser Permanente’s Division of Research, identified eleven genes that act differently in autistic children. These genes are found in the children’s natural killer cells, which are part of their immune system.

    Gabriela Quiros
    QUEST Segment Producer

  • Thank you for a great piece. I was surprised that Kaiser is cooperative in this venture given that I’ve had a very negative experience with them as regards my son; however, I hope their involvement will result in better treatment of those on the spectrum.

    For awhile I’ve tried to explain to others how I am not at either “extreme” of issues such as the vaccination one: I believe vaccines are miraculous and “herd immunity” is vital, but I also believe that those who are (genetically predisposed to be) sensitive to environmental triggers are best treated with caution.

    I am glad that your program raised this as a possibility. Rather than assuming everyone is a cookie-cutter, it makes sense that some of us might be more sensitive to particular stimuli than others. This goes for pesticides, food additives, and other factors that shouldn’t universally be considered “bad” but may just be an unfortunate trigger for a sensitive kid.

    The more the media can show that it is perfectly acceptable to have “many causes, many cures,” the better: less proclamations that parents of those on the spectrum are “bad” or that we are “crazy” for trying to “blame” our kids’ sensitivities on exterior factors. Again, thank you!

  • Pingback: Minnesota Has the Highest Autism Rate?: Depends on How You Count It()

  • Good job on this story. I am down in Los Angeles with two kids on the spectrum 12, 13. We have been in studies.

  • admin

    Hi Everyone:

    We’ve just updated the post with a link to the M.I.N.D. Institute study outlining new findings that the immune systems of autistic children are different than those of typically developing children.

  • Tatiana

    Since I am debating on vaccinations for my baby, I found your programm quite informative. Thank you.
    I was wondering if it is possible to share the schedule of vaccinations that the mother in the piece and her son’s pediatrician created. There was something mentioned about getting all the vaccinations completed by the time her son is 4 year old vs standard 2 years.

  • CS

    Autism is not an illness. I don’t have an illness. Please could you at least have interviewed some folks with credibility? The Mind Institute is funded by a mercury mom. If the man in interview wondering where all the autistic adults are, I’m one. Tell him to go to an autism support group, check the group homes in his community or simply go to Autscape. This report seems to have been generated by someone with a very clear agenda. Why were no autistic adults interviewed? There are plenty out there, if the producer would like to find some, I’d be happy to direct them in the proper direction.


Gabriela Quirós

Gabriela Quirós is a video producer for KQED Science and the coordinating producer for Deep Look. She started her journalism career 25 years ago as a newspaper reporter in Costa Rica, where she grew up. She won two national reporting awards there for series on C-sections and organic agriculture, and developed a life-long interest in health reporting. She moved to the Bay Area in 1996 to study documentary filmmaking at the University of California-Berkeley, where she received master’s degrees in journalism and Latin American studies. She joined KQED as a TV producer when its science series QUEST started in 2006 and has covered everything from Alzheimer’s to bee die-offs to dark energy. She has won five regional Emmys and has shared awards from the Jackson Hole Wildlife Film Festival, the Society of Professional Journalists and the Society of Environmental Journalists. Independent from her work in KQED's science unit, she produced and directed the hour-long documentary Beautiful Sin, about the surprising story of how Costa Rica became the only country in the world to outlaw in vitro fertilization. The film aired nationally on public television stations in 2015.

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