Why Are Autism Rates Steadily Rising?
Stefania Sterling with her son Charlie, who was diagnosed at age 3 with autism.
Stefania Sterling was just 21 when she had her son, Charlie. She was young and healthy, with no genetic issues apparent in either her or her husband's family, so she expected Charlie to be typical.
"It is surprising that the prevalence of a significant disorder like autism has risen so consistently over a relatively brief period."
It wasn't until she went to a Mommy and Me music class when he was one, and she saw all the other one-year-olds walking, that she realized how different her son was. He could barely crawl, didn't speak, and made no eye contact. By the time he was three, he was diagnosed as being on the lower functioning end of the autism spectrum.
She isn't sure why it happened – and researchers, too, are still trying to understand the basis of the complex condition. Studies suggest that genes can act together with influences from the environment to affect development in ways that lead to Autism Spectrum Disorder (ASD). But rates of ASD are rising dramatically, making the need to figure out why it's happening all the more urgent.
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Indeed, the CDC's latest autism report, released last week, which uses 2016 data, found that the prevalence of ASD in four-year-old children was one in 64 children, or 15.6 affected children per 1,000. That's more than the 14.1 rate they found in 2014, for the 11 states included in the study. New Jersey, as in years past, was the highest, with 25.3 per 1,000, compared to Missouri, which had just 8.8 per 1,000.
The rate for eight-year-olds had risen as well. Researchers found the ASD prevalence nationwide was 18.5 per 1,000, or one in 54, about 10 percent higher than the 16.8 rate found in 2014. New Jersey, again, was the highest, at one in 32 kids, compared to Colorado, which had the lowest rate, at one in 76 kids. For New Jersey, that's a 175 percent rise from the baseline number taken in 2000, when the state had just one in 101 kids.
"It is surprising that the prevalence of a significant disorder like autism has risen so consistently over a relatively brief period," said Walter Zahorodny, an associate professor of pediatrics at Rutgers New Jersey Medical School, who was involved in collecting the data.
The study echoed the findings of a surprising 2011 study in South Korea that found 1 in every 38 students had ASD. That was the the first comprehensive study of autism prevalence using a total population sample: A team of investigators from the U.S., South Korea, and Canada looked at 55,000 children ages 7 to 12 living in a community in South Korea and found that 2.64 percent of them had some level of autism.
Searching for Answers
Scientists can't put their finger on why rates are rising. Some say it's better diagnosis. That is, it's not that more people have autism. It's that we're better at detecting it. Others attribute it to changes in the diagnostic criteria. Specifically, the May 2013 update of the Diagnostic and Statistical Manual of Mental Disorders-5 -- the standard classification of mental disorders -- removed the communication deficit from the autism definition, which made more children fall under that category. Cynical observers believe physicians and therapists are handing out the diagnosis more freely to allow access to services available only to children with autism, but that are also effective for other children.
Alycia Halladay, chief science officer for the Autism Science Foundation in New York, said she wishes there were just one answer, but there's not. While she believes the rising ASD numbers are due in part to factors like better diagnosis and a change in the definition, she does not believe that accounts for the entire rise in prevalence. As for the high numbers in New Jersey, she said the state has always had a higher prevalence of autism compared to other states. It is also one of the few states that does a good job at recording cases of autism in its educational records, meaning that children in New Jersey are more likely to be counted compared to kids in other states.
"Not every state is as good as New Jersey," she said. "That accounts for some of the difference compared to elsewhere, but we don't know if it's all of the difference in prevalence, or most of it, or what."
"What we do know is that vaccinations do not cause autism."
There is simply no defined proven reason for these increases, said Scott Badesch, outgoing president and CEO of the Autism Society of America.
"There are suggestions that it is based on better diagnosis, but there are also suggestions that the incidence of autism is in fact increasing due to reasons that have yet been determined," he said, adding, "What we do know is that vaccinations do not cause autism."
Zahorodny, the pediatrics professor, believes something is going on beyond better detection or evolving definitions.
"Changes in awareness and shifts in how children are identified or diagnosed are relevant, but they only take you so far in accounting for an increase of this magnitude," he said. "We don't know what is driving the surge in autism recorded by the ADDM Network and others."
He suggested that the increase in prevalence could be due to non-genetic environmental triggers or risk factors we do not yet know about, citing possibilities including parental age, prematurity, low birth rate, multiplicity, breech presentation, or C-section delivery. It may not be one, but rather several factors combined, he said.
"Increases in ASD prevalence have affected the whole population, so the triggers or risks must be very widely dispersed across all strata," he added.
There are studies that find new risk factors for ASD almost on a daily basis, said Idan Menashe, assistant professor in the Department of Health at Ben-Gurion University of the Negev, the fastest growing research university in Israel.
"There are plenty of studies that find new genetic variants (and new genes)," he said. In addition, various prenatal and perinatal risk factors are associated with a risk of ASD. He cited a study his university conducted last year on the relationship between C-section births and ASD, which found that exposure to general anesthesia may explain the association.
Whatever the cause, health practitioners are seeing the consequences in real time.
"People say rates are higher because of the changes in the diagnostic criteria," said Dr. Roseann Capanna-Hodge, a psychologist in Ridgefield, CT. "And they say it's easier for children to get identified. I say that's not the truth and that I've been doing this for 30 years, and that even 10 years ago, I did not see the level of autism that I do see today."
Sure, we're better at detecting autism, she added, but the detection improvements have largely occurred at the low- to mid- level part of the spectrum. The higher rates of autism are occurring at the more severe end, in her experience.
A Polarizing Theory
Among the more controversial risk factors scientists are exploring is the role environmental toxins may play in the development of autism. Some scientists, doctors and mental health experts suspect that toxins like heavy metals, pesticides, chemicals, or pollution may interrupt the way genes are expressed or the way endocrine systems function, manifesting in symptoms of autism. But others firmly resist such claims, at least until more evidence comes forth. To date, studies have been mixed and many have been more associative than causative.
"Today, scientists are still trying to figure out whether there are other environmental changes that can explain this rise, but studies of this question didn't provide any conclusive answer," said Menashe, who also serves as the scientific director of the National Autism Research Center at BGU.
"It's not everything that makes Charlie. He's just like any other kid."
That inconclusiveness has not dissuaded some doctors from taking the perspective that toxins do play a role. "Autism rates are rising because there is a mismatch between our genes and our environment," said Julia Getzelman, a pediatrician in San Francisco. "The majority of our evolution didn't include the kinds of toxic hits we are experiencing. The planet has changed drastically in just the last 75 years –- it has become more and more polluted with tens of thousands of unregulated chemicals being used by industry that are having effects on our most vulnerable."
She cites BPA, an industrial chemical that has been used since the 1960s to make certain plastics and resins. A large body of research, she says, has shown its impact on human health and the endocrine system. BPA binds to our own hormone receptors, so it may negatively impact the thyroid and brain. A study in 2015 was the first to identify a link between BPA and some children with autism, but the relationship was associative, not causative. Meanwhile, the Food and Drug Administration maintains that BPA is safe at the current levels occurring in food, based on its ongoing review of the available scientific evidence.
Michael Mooney, President of St. Louis-based Delta Genesis, a non-profit organization that treats children struggling with neurodevelopmental delays like autism, suspects a strong role for epigenetics, which refers to changes in how genes are expressed as a result of environmental influences, lifestyle behaviors, age, or disease states.
He believes some children are genetically predisposed to the disorder, and some unknown influence or combination of influences pushes them over the edge, triggering epigenetic changes that result in symptoms of autism.
For Stefania Sterling, it doesn't really matter how or why she had an autistic child. That's only one part of Charlie.
"It's not everything that makes Charlie," she said. "He's just like any other kid. He comes with happy moments. He comes with sad moments. Just like my other three kids."
Henrietta Lacks' Cells Enabled Medical Breakthroughs. Is It Time to Finally Retire Them?
Henrietta Lacks, (1920-1951) unknowingly had her cells cultured and used in medical research.
For Victoria Tokarz, a third-year PhD student at the University of Toronto, experimenting with cells is just part of a day's work. Tokarz, 26, is studying to be a cell biologist and spends her time inside the lab manipulating muscle cells sourced from rodents to try to figure out how they respond to insulin. She hopes this research could someday lead to a breakthrough in our understanding of diabetes.
"People like to use HeLa cells because they're easy to use."
But in all her research, there is one cell culture that Tokarz refuses to touch. The culture is called HeLa, short for Henrietta Lacks, named after the 31-year-old tobacco farmer the cells were stolen from during a tumor biopsy she underwent in 1951.
"In my opinion, there's no question or experiment I can think of that validates stealing from and profiting off of a black woman's body," Tokarz says. "We're not talking about a reagent we created in a lab, a mixture of some chemicals. We're talking about a human being who suffered indescribably so we could profit off of her misfortune."
Lacks' suffering is something that, until recently, was not widely known. Born to a poor family in Roanoke, VA, Lacks was sent to live with her grandfather on the family tobacco farm at age four, shortly after the death of her mother. She gave birth to her first child at just fourteen, and two years later had another child with profound developmental disabilities. Lacks married her first cousin, David, in 1941 and the family moved to Maryland where they had three additional children.
But the real misfortune came in 1951, when Lacks told her cousins that she felt a hard "knot" in her womb. When Lacks went to Johns Hopkins hospital to have the knot examined, doctors discovered that the hard lump Henrietta felt was a rapidly-growing cervical tumor.
Before the doctors treated the tumor – inserting radium tubes into her vagina, in the hopes they could kill the cancer, Lacks' doctors clipped two tissue samples from her cervix, without Lacks' knowledge or consent. While it's considered widely unethical today, taking tissue samples from patients was commonplace at the time. The samples were sent to a cancer researcher at Johns Hopkins and Lacks continued treatment unsuccessfully until she died a few months later of metastatic cancer.
Lacks' story was not over, however: When her tissue sample arrived at the lab of George Otto Gey, the Johns Hopkins cancer researcher, he noticed that the cancerous cells grew at a shocking pace. Unlike other cell cultures that would die within a day or two of arriving at the lab, Lacks' cells kept multiplying. They doubled every 24 hours, and to this day, have never stopped.
Scientists would later find out that this growth was due to an infection of Human Papilloma Virus, or HPV, which is known for causing aggressive cancers. Lacks' cells became the world's first-ever "immortalized" human cell line, meaning that as long as certain environmental conditions are met, the cells can replicate indefinitely. Although scientists have cultivated other immortalized cell lines since then, HeLa cells remain a favorite among scientists due to their resilience, Tokarz says.
"People like to use HeLa cells because they're easy to use," Tokarz says. "They're easy to manipulate, because they're very hardy, and they allow for transection, which means expressing a protein in a cell that's not normally there. Other cells, like endothelial cells, don't handle those manipulations well."
Once the doctors at Johns Hopkins discovered that Lacks' cells could replicate indefinitely, they started shipping them to labs around the world to promote medical research. As they were the only immortalized cell line available at the time, researchers used them for thousands of experiments — some of which resulted in life-saving treatments. Jonas Salk's polio vaccine, for example, was manufactured using HeLa cells. HeLa cell research was also used to develop a vaccine for HPV, and for the development of in vitro fertilization and gene mapping. Between 1951 and 2018, HeLa cells have been cited in over 110,000 publications, according to a review from the National Institutes of Health.
But while some scientists like Tokarz are thankful for the advances brought about by HeLa cells, they still believe it's well past time to stop using them in research.
"Am I thankful we have a polio vaccine? Absolutely. Do I resent the way we came to have that vaccine? Absolutely," Tokarz says. "We could have still arrived at those same advances by treating her as the human being she is, not just a specimen."
Ethical considerations aside, HeLa is no longer the world's only available cell line – nor, Tokarz argues, are her cells the most suitable for every type of research. "The closer you can get to the physiology of the thing you're studying, the better," she says. "Now we have the ability to use primary cells, which are isolated from a person and put right into the culture dish, and those don't have the same mutations as cells that have been growing for 20 years. We didn't have the expertise to do that initially, but now we do."
Raphael Valdivia, a professor of molecular genetics and microbiology at Duke University School of Medicine, agrees that HeLa cells are no longer optimal for most research. "A lot of scientists are moving away from HeLa cells because they're so unstable," he says. "They mutate, they rearrange chromosomes to become adaptive, and different batches of cells evolve separately from each other. The HeLa cells in my lab are very different than the ones down the hall, and that means sometimes we can't replicate our results. We have to go back to an earlier batch of cells in the freezer and re-test."
Still, the idea of retiring the cells completely doesn't make sense, Valdivia says: "To some extent, you're beholden to previous research. You need to be able to confirm findings that happen in earlier studies, and to do that you need to use the same cell line that other researchers have used."
"Ethics is not black and white, and sometimes there's no such thing as a straightforward ethical or unethical choice."
"The way in which the cells were taken – without patient consent – is completely inappropriate," says Yann Joly, associate professor at the Faculty of Medicine in Toronto and Research Director at the Centre of Genomics and Policy. "The question now becomes, what can we do about it now? What are our options?"
While scientists are not able to erase what was done to Henrietta Lacks, Joly argues that retiring her cells is also non-consensual, assuming – maybe incorrectly – what Henrietta would have wanted, without her input. Additionally, Joly points out that other immortalized human cell lines are fraught with what some people consider to be ethical concerns as well, such as the human embryonic kidney cell line, commonly referred to as HEK-293, that was derived from an aborted female fetus. "Just because you're using another kind of cell doesn't mean it's devoid of ethical issue," he says.
Seemingly, the one thing scientists can agree on is that Henrietta Lacks was mistreated by the medical community. But even so, retiring her cells from medical research is not an obvious solution. Scientists are now using HeLa cells to better understand how the novel coronavirus affects humans, and this knowledge will inform how researchers develop a COVID-19 vaccine.
"Ethics is not black and white, and sometimes there's no such thing as a straightforward ethical or unethical choice," Joly says. "If [ethics] were that easy, nobody would need to teach it."
An intergalactic explorer on a hypothetical mission to Mars.
Social isolation. Strange pathogens outside. Strategic resource planning. Our Earthbound pandemic-driven social distancing could be mistaken for adapting to another, foreign planet. After all, we're donning all our protective apparel to go on an airplane or to the grocery store, nevertheless to just open our front door. Perhaps this is training for the world galactic visionaries Elon Musk, Jeff Bezos, and Richard Branson see in our future.
"There are parallels to the individual psychological experience, but from an operational standpoint, it is too different."
Ready to go live on Mars or something? Not so fast, experts say. The experience of shelter in place isn't parallel to being a space settler, or even an astronaut.
"Certain aspects are similar, but still, honestly, there are too many differences to say it preps us," says Angelo Vermeulen, co-founder of the art-science collective SEADS (Space Ecologies Art and Design) Network. In 2013, he served as a NASA crew commander for a four-month Mars-on-Earth mission, isolated in a geometric biodome with five others. "There are parallels to the individual psychological experience, but from an operational standpoint, it is too different. You don't need a spacesuit, aren't threatened by a thin atmosphere or worried about being overpowered by radiation."
Outside threats aside, we have a bigger experience gap: Most of us didn't see this pandemic coming and weren't trained to survive the current new normal. NASA astronauts get at least two years of basic training. We received none. Intergalactic explorers understand gravity, air pressure, and other important criteria based on decades of space knowledge. Alternatively, new novel coronavirus data is coming in real time, changing the threats, precautions, and needs dramatically. Things feel a little different when you're winging it.
Lastly, with respect to Apollo 13, space travelers have a timeline for when their experience will be over. There are mishaps, challenges and adjustments, but every well-supported journeyperson leaves Earth with an agenda (and a team back home to help keep them on track).
The pandemic, on the other hand, has no definitive end. It is unclear when a reliable vaccine will be readily available. It is also not known how long we should shelter-in-place, as pulling the trigger too early could bring another wave of illness. We are missing definitive milestones, which, Vermeulen says, would make our isolation experience easier to navigate. "When you're on a mission, the end date is always on the horizon. You can celebrate the midpoint and check off major milestones, which helps."
Also, unlike a kid pretending to be in a rocket, most of us didn't dream of one day being socially isolated for an indeterminate amount of time. "If you're ambitious and working in the field, then it is your goal in life to experience [space and the related isolation]," he says. "With the pandemic, though, nobody chose to do this."
[Editor's Note: This article was originally published on June 8th, 2020 as part of a standalone magazine called GOOD10: The Pandemic Issue. Produced as a partnership among LeapsMag, The Aspen Institute, and GOOD, the magazine is available for free online.]