Since autism was first added to the psychiatric literature fifty years ago, there have been numerous studies and theories about its cause. Researchers still have not reached agreement regarding its specific causes. First, it must be recognized that autism is a set of a wide variety of symptoms and may have many causes. This concept is not unusual in medicine. For instance, the set of symptoms that we perceive of as a “cold” can be caused by literally hundreds of different viruses, bacteria, and even our own immune system. Autism is, undoubtedly, a biologically-based disorder. In the past, some researchers had suggested that autism was the result of poor attachment skills on the part of the mother. This belief has caused a great deal of unnecessary pain and guilt on the part of the parents of autistic children, when in fact, the inability of the individual with autism to interact appropriately is one of the key symptoms of this developmental disorder.

In support of a biological theory of autism, several known neurological disorders are associated with autistic features. Autism is one of the symptoms of these disorders. These conditions include tuberous sclerosis (an inherited disorder), the fragile X syndrome, cerebral dysgenesis (abnormal development of the brain), Rett syndrome, and some of the inborn errors of metabolism (biochemical defects). Autism, in short, seems to be the end result or “final common pathway” of numerous disorders that affect brain development. In general, however, when clinicians make the diagnosis of autism, they are excluding the known causes of autistic behaviors. However, as the knowledge of conditions that cause autism advances, fewer and fewer cases will be thought of as being “pure” autism and more individuals will be identified as having autism due to specific causes.

There is a strong association between autism and seizures. This association works in two ways: First, many patients (20% to 30%) with autism develop seizures. Second, patients with seizures, which are probably due to other causes, may develop autistic-like behaviors. One special and often misunderstood association between autism and seizures is the Landau-Kleffner Syndrome. This syndrome is also known as acquired epileptic aphasia. Some children with epilepsy develop a sudden loss of language skills–especially receptive language (the ability to understand). Many often also develop the symptoms of autism.

These children often, but not always, have a characteristic pattern of electrical brain activity seen on EEG (electroencephalogram) during deep sleep called electrographic status epilepticus during sleep (ESES). The usual age of onset of language loss or regression is around four years of age, which makes the Landau-Kleffner syndrome distinguishable from autism on these grounds, in that autism usually is first exhibited in younger children. However, in recent years, some children (very, very few) who did not exhibit overt (observable) seizures were found to have Landau-Kleffner syndrome.

The importance of these findings is that, although rare, the Landau-Kleffner syndrome can resolve spontaneously and in some cases can be treatable with prednisone, a steroid medication related to cortisone. This association between the Landau-Kleffner syndrome and autism has led many clinicians and families to search for the typical EEG pattern (ESES) in autistic individuals. This unusual EEG pattern is seen only in deep sleep, which usually requires prolonged recordings of up to 12 hours. Many, many autistic children and adults will display some abnormalities on their sleep EEG, but probably very few have true Landau-Kleffner syndrome that will respond to treatment.

It must also be noted that prednisone, in the very high doses used to treat Landau-Kleffner syndrome, almost invariably produces side effects, which may include weight gain, high blood pressure, diabetes, growth failure, stomach ulcers, irritability, destruction of the hip joint, and susceptibility to infectious disease (suppressed immune system). While most of these side effects are reversible, some of the complications of high dose prednisone therapy can be irreversible and even fatal.

Other treatments ranging from common anticonvulsant therapy to surgery have been proposed and are being tried for Landau-Kleffner syndrome. It is difficult to evaluate the true effects of any treatment for Landau-Kleffner syndrome due to the high rate of spontaneous resolution of symptoms (remission).

Hours after a baby is born, her parents are told it’s best that she receive her first shot before she leaves the hospital. And that’s just the beginning. By the child’s sixth birthday, she’ll have had at least 35 vaccinations—if she goes by government recommendations. Meanwhile, during those six years, her parents are likely to see hundreds of media reports and online message-board debates about which vaccines are necessary or even safe. It’s confusing, to say the least.

To sort through the onslaught of information and misinformation about childhood immunizations, we asked Austin, Texas-based pediatrician Ari Brown, coauthor of “Baby 411: Clear Answers and Smart Advice for your Baby’s First Year,” to debunk some of the most common vaccination myths.

Myth 1: It’s not necessary to vaccinate kids against diseases that have been largely eradicated in the United States.
Reality: Although some diseases like polio and diphtheria aren’t often seen in America (in large part because of the success of the vaccination efforts), they can be quite common in other parts of the world. The Centers for Disease Control and Prevention warns that travelers can unknowingly bring these diseases into the United States, and if we were not protected by vaccinations, these diseases could quickly spread throughout the population. At the same time, the relatively few cases currently in the U.S. could very quickly become tens or hundreds of thousands of cases without the protection we get from vaccines. Brown warns that these diseases haven’t disappeared, “they are merely smoldering under the surface.”

Most parents do follow government recommendations: U.S. national immunization rates are high, ranging from 85 percent to 93 percent, depending on the vaccine, according to the CDC. But according to a 2006 study in the Journal of the American Medical Association, the 20 states that allow personal-belief opt outs in addition to religious exemptions saw exemptions grow by 61 percent, to 2.54 percent between 1991 and 2004.

Brown is concerned that parents who opt out or stagger the vaccine schedule can end up having to deal with confusing follow-up care, which could produce an increase in disease outbreaks like last summer’s measles epidemic. A 2008 study in the American Journal of Epidemiology reported that when there are more exemptions, children are at an increased risk of contracting and transmitting vaccine-preventable diseases.

Myth 2: Mercury is still in kids’ vaccines.
Reality: At the center of this issue is a preservative called thimerosal compound containing mercury) that once was a common component in many vaccines because it allowed manufacturers to make drugs more cheaply and in multidose formulations. But public concern, new innovations and FDA recommendations led to its removal from almost all children’s vaccines manufactured after 2001. Since flu vaccines are not just for children, manufacturers still put thimerosal in some flu-shot formulations. You can ask your pediatrician for the thimerosal-free version, says Brown.

If your child does not have asthma and is at least 2 years old, Brown recommends the FluMist nasal-spray vaccination over the flu shot. “It seems to have better immune protection and it could help your child avoid another shot,” she says. (Caveat: the spray does contain a live version of the virus, which can result in a slight increase in flulike symptoms).

Myth 3: Childhood vaccines cause autism.
Reality: There is no scientific evidence that this link exists. Groups of experts, including the American Academy of Pediatrics and the Institute of Medicine (IOM), agree that vaccines are not responsible for the growing number of children now recognized to have autism.

Earlier this month, the law supported scientists’ conclusions in this arena with three rulings from a section of the U.S. Court of Federal Claims, which stated that vaccines were not the likely cause of autism in three unrelated children. The U.S. Department of Health and Human Services said in an online statement following the ruling, “The medical and scientific communities have carefully and thoroughly reviewed the evidence concerning the vaccine-autism theory and have found no association between vaccines and autism.” Noting the volume of scientific evidence disproving this link, an executive member of one of the nation’s foremost autism advocacy groups, Autism Speaks, recently stepped down from her position because she disagrees with the group’s continued position that there is a connection between the vaccines and autism.

Myth 4: Getting too many vaccines can overwhelm the immune system and cause adverse reactions or even serious illness.
Reality: Children’s immune systems are capable of combating far more antigens (weak or killed viruses) than they encounter via immunizations. In fact, the jury is still out on if there’s an actual limit on how many the body can handle—though one study puts the number around a theoretical 10,000 vaccines in one day.(Visit the American Academy of Pediatrics’ site or the Network for Immunization Information for more information)

Currently, “There is even less of a burden on the immune system [via vaccines] today than 40 years ago,” says Edgar Marcuse, a professor of pediatrics at the University of Washington who works on immunization policy and vaccines. He points to the whooping-cough vaccine as an example where there are far fewer antigens in the shot than the earlier version administered decades ago. Brown says she supports following the recommended schedule for vaccinations, which outlines getting as many as five shots in one day at a couple check-ups.

The CDC reports that most vaccine adverse events are minor and temporary, such as a sore arm or mild fever and “so few deaths can plausibly be attributed to vaccines that it is hard to assess the risk statistically.” Of all deaths reported to the Health and Human Services’ Vaccine Adverse Events Reporting site between 1990 and 1992, only one is believed to be even possibly associated with a vaccine. The Vaccine Safety Datalink Project, an initiative of the CDC and eight health-care organizations, looks for patterns in these reports and determines if a vaccine is causing a side effect or if symptoms are largely coincidental.

If you have concerns about following the recommended vaccination, schedules don’t wait until a check-up. Set up a consultation appointment with your pediatrician, or even outline a strategy for care with your doctor during your pregnancy.

Myth 5: It’s better to let my kid get chickenpox “naturally.”
Reality: Before the chickenpox vaccine was licensed in 1995, parents sometimes brought their child to a party or playground hoping that their child might brush up against a pox-laden kid to get their dose of chickenpox over since cases were usually less severe for children than adults. But pediatricians say severe complications are possible with chickenpox—including bacterial infections that could result in a child’s hospitalization or death.

Now that there’s a vaccine for chickenpox, more than 45 states require the shots (unless your child already had the chicken pox or can prove natural immunity). Two shots usually guarantees your child a way out of being bedecked in calamine lotion for two feverish weeks, but some individuals do still come down with a milder form of the pox. Most pediatricians recommend getting the shot.

Myth 6: The flu shot causes the flu.
Reality: The flu shot does not contain a live virus, so your child can’t get the flu from this shot. But, after the shot, it’s not uncommon to feel a bit achy while the immune system mounts its response. Remember that for two weeks following the shot, your child can still get the flu, so be sure to help your child avoid that feverish kid next door.

Like many people in London on that bleak February day in 1998, biochemist Nicholas Chadwick was eager to hear what the scientists would say. The Royal Free Hospital, where he was a graduate student in the lab of gastroenterologist Andrew Wakefield, had called a press conference to unveil the results of a new study. With flashbulbs popping, Wakefield stepped up to the bank of microphones: he and his colleagues, he said, had discovered a new syndrome that they believed was triggered by the MMR (measles, mumps, rubella) vaccine. In eight of the 12 children in their study, being published that day in the respected journal The Lancet, they had found severe intestinal inflammation, with the symptoms striking six days, on average, after the children received the MMR. But hospitals don’t hold elaborate press conferences for studies of gut problems. The reason for all the hoopla was that nine of the children in the study also had autism, and the tragic disease had seized them between one and 14 days after their MMR jab. The vaccine, Wakefield suggested, had damaged the intestine—in particular, the measles part had caused serious inflammation—allowing harmful proteins to leak from the gut into the bloodstream and from there to the brain, where they damaged neurons in a way that triggered autism. Although in their paper the scientists noted that “we did not prove an association” between the MMR and autism, Wakefield was adamant. “It’s a moral issue for me,” he said, “and I can’t support the continued use of [the MMR] until this issue has been resolved.”

That’s strange, thought Chadwick. For months he had been extracting genetic material from children’s gut biopsies, looking for evidence of measles from the MMR. That was the crucial first link in the chain of argument connecting the MMR to autism: the measles virus infects the gut, causing inflammation and leakage, then gut leakage lets neurotoxin compounds into the blood and brain. Yet Chadwick kept coming up empty-handed. “There were a few cases of false positives, [but] essentially all the samples tested were negative,” he later told a judicial hearing. When he explained the negative results, he told NEWSWEEK, Wakefield “tended to shrug his shoulders. Even in lab meetings he would only talk about data that supported his hypothesis. Once he had his theory, he stuck to it no matter what.” Chadwick was more disappointed than upset, figuring little would come from the Lancet study. “Not many people thought [Wakefield] would be taken that seriously,” Chadwick recalls. “We thought most people would see the Lancet paper for what it was—a very preliminary collection of [only 12] case reports. How wrong we were.”

The next day, headlines in the British press screamed, DOCTORS LINK AUTISM TO MMR VACCINE AND BAN THREE-IN-ONE JAB, URGE DOCTORS AFTER NEW FEARS. That was mild compared with what followed. Hysteria over childhood vaccinations built to such a crescendo that Wakefield’s nuanced warning—that it was specifically the triple vaccine, not single-disease vaccines (even measles), that posed a threat—was drowned out. In 2001, Prime Minister Tony Blair and his wife, Cherie, refused to say whether their son, then 19 months old, had received the MMR; rumors swirled that they had gone to France so the child could receive the measles vaccine alone. In 2003, a docudrama about Wakefield ran on British TV, depicting him as having his files stolen and his phone tapped by evil pharmaceutical companies intent on protecting their vaccines. As one reviewer described the show: “The MMR vaccine is coming to get our kids.”

vaccines (of which U.S. health officials recommend 35 by age 6) started a backlash in the United States, too, fueled in no small part by the fact that the incidence of autism was rising for reasons scientists could not fully explain. In California, for instance, the incidence of autism had risen from 6.2 per 10,000 births in 1990 to 42.5 in 2001. Groups of parents began refusing vaccines for their children. Within a few years of Wakefield’s announcement, rates of MMR vaccinations in Britain fell from 92 percent to below 80 percent. Although there was no comparable nationwide decrease in the United States, pockets of resistance to vaccination appeared throughout the country, laying the groundwork for a sevenfold increase in measles outbreaks. Looking back from the perspective of 11 years, the panic seems both inevitable and inexplicable. Inevitable, because legitimate scientists publishing in respected journals produced evidence of a link between vaccines and autism, and because the press as well as politicians and even public-health officials stoked the mounting hysteria. Inexplicable because, by the early 2000s, scientific support for that link had evaporated as completely as the red dot on a baby’s vaccinated thigh.

Scientists and government officials who defended the safety of childhood vaccines were not shy about attributing the fears to the science illiteracy of the public and the fear mongering of the press. In truth, however, after Wakefield’s announcement there was a steady drumbeat of studies—not from kooks in basement labs but from real scientists working at real institutions and publishing in real, peer-reviewed journals—that backed him up. In 2002, pathologist John O’Leary of Coombe Women’s Hospital in Dublin reported that he had found RNA from the measles virus in 7 percent of normal children—but in 82 percent of those with autism, suggesting that some children are unable to clear the vaccinated virus from their systems, resulting in autism. That same year, a Utah State University biologist reported finding high levels of antibodies against the measles virus in the blood and spinal fluid of autistic children; the MMR, he postulated, had triggered a hyper immune response that attacked the children’s brains. In 2003, gastroenterologist Arthur Krigsman, then at New York University School of Medicine, reported finding what Wakefield had: that the guts of 40 autistic children were severely inflamed, lending support to the idea that leaks allowed pernicious compounds to make a beeline for the brain.

But these studies and others supporting the link between autism and the MMR were nothing compared with an extraordinary step that had been taken by the U.S. government and by one of the country’s leading medical organizations. On July 7, 1999, the American Academy of Pediatrics (AAP) and the U.S. Public Health Service issued a warning about the preservative in many vaccines. Called thimerosal, it contains 49.6 percent ethyl mercury by weight and had been used in vaccines since the 1930s, including the diphtheria/tetanus/pertussis (DTP) and Haemophilus influenzae (Hib) vaccines (but not the MMR). The experts tried to be reassuring, saying in a statement there are “no data or evidence of any harm” from thimerosal. But, they continued, children’s cumulative exposure to mercury from vaccines “exceeds one of the federal safety guidelines” for mercury. (By 2003, most childhood vaccines did not contain thimerosal, though flu vaccines still did.) The AAP statement did not mention autism

What is Rett Syndrome

Rett syndrome is a relatively rare condition that almost exclusively affects females. It occurs in one out of every 10,000 to 15,000 people.

Rett syndrome is part of a category of disorders known as pervasive developmental disorders (PDD), which are more commonly known as autism spectrum disorders. All of these disorders are characterized by varying degrees of:

• Impairment in communication skills and social interactions
• Restricted, repetitive, and stereotyped patterns of behavior.

Symptoms of Rett Syndrome

People who develop Rett syndrome initially go through a period of normal development that lasts between 6 and 18 months. After that, autism-like symptoms begin to appear. The little girl’s mental and social development regresses — she no longer responds to her parents and pulls away from any social contact. If she has been talking, she stops; she cannot control her feet; she wrings her hands. Some of the problems associated with Rett syndrome can be treated. Physical, occupational, and speech therapy can help with problems of coordination, movement, and speech.

Causes of Rett Syndrome

Scientists have discovered that a mutation in the sequence of a single gene can cause Rett syndrome. This discovery may help doctors slow or stop the progression of the syndrome. It may also lead to methods of screening for Rett syndrome. This would enable doctors to treat — and thus improve the quality of life of — these children much sooner.