Another study shows vaccines do not cause autism

Quinn, an autistic boy, and the line of toys he made before falling asleep. Repeatedly stacking or lining up objects is a behavior commonly associated with autism. Credit: Wikipedia.

(Medical Xpress)—A team of researchers with affiliations to several institutions in the U.S., has conducted a study at the University of Texas Southwestern Medical Center in Dallas, Texas, looking into the possibility of vaccines or the preservative thimerosal causing autism spectrum disorders (ASDs) and has found no such link. In their paper published in Proceedings of the National Academy of Sciences, the team describes their study using Rhesus monkeys and what they found as a result of their work.

For several years parents and citizen groups have claimed that vaccinations (and/or a preservative used to keep them fresh) given to infants and children causes ASDs , despite the lack of evidence. Such suspicions got their start due to the onset of a disorder in many cases, shortly after a vaccination was given—most scientists believe such instances were merely coincidences. Over the same time span, many studies have been done to determine if such claims are true, and only one, by a now discredited doctor, found any validity to the argument. To pacify worried parents, the preservative thimerosal has been mostly phased out. In this new study the team ran an inoculation schedule on a large group of rhesus monkey infants to see if they developed any of the symptoms of an ASD.

The researchers inoculated 79 of the (whose brains and physiology are very similar to humans), varying the age at which they were given and a combination of vaccines, and of course with or without themersol. They also injected a control group with a . Some of the monkeys got the same regimen as children in the U.S. received during the 1990's or in 2008. Afterwards, all of the monkeys were monitored to see if they developed ASD type symptoms—none did. The researchers also killed some of the monkeys in order to perform brain autopsies, once again looking for hallmarks of an ASD, and once again, none were found.

The team reports that no evidence of any ASD was found in any of the monkeys, and thus rejects the hypothesis that vaccines alone or with thimerosal are the cause of a rise in the number of children diagnosed with such disorders over the past several decades.

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Another study finds no link between vaccine, autism

More information: Administration of thimerosal-containing vaccines to infant rhesus macaques does not result in autism-like behavior or neuropathology, Bharathi S. Gadad, DOI: 10.1073/pnas.1500968112

Autism spectrum disorder (ASD) is a complex neurodevelopmental disorder. Some anecdotal reports suggest that ASD is related to exposure to ethyl mercury, in the form of the vaccine preservative, thimerosal, and/or receiving the measles, mumps, rubella (MMR) vaccine. Using infant rhesus macaques receiving thimerosal-containing vaccines (TCVs) following the recommended pediatric vaccine schedules from the 1990s and 2008, we examined behavior, and neuropathology in three brain regions found to exhibit neuropathology in postmortem ASD brains. No neuronal cellular or protein changes in the cerebellum, hippocampus, or amygdala were observed in animals following the 1990s or 2008 vaccine schedules. Analysis of social behavior in juvenile animals indicated that there were no significant differences in negative behaviors between animals in the control and experimental groups. These data indicate that administration of TCVs and/or the MMR vaccine to rhesus macaques does not result in neuropathological abnormalities, or aberrant behaviors, like those observed in ASD.

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Sep 29, 2015
How useful is this study? Do rhesus monkeys develop autism spectrum disorder?

If you want to study if people develop ASD from vaccines, it seems that the subject population should be human.

Sep 29, 2015
While the scientific basis for vaccines is solid, the questions people have about the manufacture need to have valid apples to apples studies;
Vaccines are grown in stem cell strains derived from cell lines originally taken from human aborted tissues. While this growth medium eliminates some problems and side effects of using non human growth medium (animal tissue, duck eggs) can the human variable help trigger autoimmune reactions in those who are susceptible?
Not related to vaccines, the same question is being asked about what triggers the genetic link to cancer to wake up and become active.
As Dogbert said, and I add to, How do you diagnose autism in a monkey?
A parallel study could be done in monkeys if you had valid monkey vaccines grown in monkey stem cells for valid monkey diseases. Then you could determine if monkeys get adverse effects. But you would still have the non-valid human result. Only a suggestion that the same thing MIGHT happen in humans.

Sep 29, 2015
Vaccination in the best case is useless practice. At the worst can cause dead or severe damage to the organism. This is the most unnatural practice in the whole history of medicine and surrounds a natural human defense mechanisms. The result is boom autoimmune diseases. Immunity is not created by vaccination. Raising the immunity is natural process.

Sep 29, 2015
Autism aside, thousands of children suffer adverse side effects to vaccines every year. Pain, numbness, rash, fever and swelling and, in many cases, serious neurological problems and death. And, yet, the effectiveness or value is very limited. If vaccines provide any immunity (which is somewhat dubious since a majority of the people infected during an outbreak have, in fact, been vaccinated), it is fully diminished within 5 years. Whether there is a link to autism is unknown (since we don't know what causes or triggers autism, we can't conclusively rule anything out). I don't need a link to autism to determine that vaccines represent more risk than reward.

Sep 29, 2015
Vaccination is a statistical gamble. There is always a small chance that one will have an adverse reaction of some sort. However, the benefits strongly outweigh the risks, both from a population perspective as well as an individual perspective.

I've seen what happens with vaccinations that go awry. It isn't pleasant. However, the disease itself is at least as bad if not worse. The problem is that every time this happens, some creep comes out of the woodwork looking for a way to make money off of someone's misery. The problem is that ultimately we are gambling that the cure is not going to be worse than the disease. And for the vast majority, the cure is worth while. Let's not throw out all the good that comes of it just because we can't make this "perfectly safe."

Sep 30, 2015
Universities do not undertake research like this without outside funding. Without disclosing the ultimate source of that funding, it's impossible to know whether "confirmation bias" is in play. All studies of this nature should disclose the source of funding. NIDA research, for example, is the poster child for confirmation bias --- billions spent on marijuana research over 50 years and not one shred of evidence that cannabinoids have health benefits. What I'd like to see is vaccine research performed outside the pale of Big Pharma.

Note to editors: thimerisal is misspelled once in the article. Also the headline is too strong: not "shows" but "finds" would be more accurate, unless you are taking the editorial position that the science on vaccine safety is "settled" (if history tells us anything, it is that "settled science" is an oxymoron.)

Oct 02, 2015
With more and more bacteria etc developing more resistance to antibiotics, and with still-limited ways to tackle severe viral infections, vaccines are the only reliable way forwards.

Snag is uptake must be high to prevent 'Refuseniks' triggering epidemics.

The new HPV vaccine should prevent a swathe of cancers some decades down-the line, yet the anti-vaxxers are up in arms.

Remember TB ? The so-sad sanitoriums ? The BCG 'test' ? Yup, I've a scar on my arm, and proud of it.

Remember tetanus ? And the 'anti-tet' vaccination that prevented trivial injuries turning lethal ?

Remember small-pox ? And the way countries would close their borders, bar you if you didn't have a certificate ?

Remember polio ? Those crippled kids in their 'iron lungs' ? Okay, the vaccine must switch from 'attenuated' to 'dead' to prevent 'tribal area' outbreaks, and there's purblind preachers to tackle...


Oct 03, 2015

The new HPV vaccine should prevent a swathe of cancers some decades down-the line, yet the anti-vaxxers are up in arms.

And they try to force young women to be vaccinated while actively discouraging young men from getting the vaccine. Such policies make no sense whatsoever.

Remember TB ?

There is no vaccine for TB.

Remember small-pox ?

Yes. Vaccination no longer needed.

Remember polio ?

Yes. And it would have been eradicated by now except for a few countries which refuse to cooperate in its eradication.

Remember tetanus ?

Yep, a very bad disease which can be controlled safely and effectively with vaccination.

The problem is that we vaccinate for minor diseases, multiple doses to young children multiple times in an assault on their developing immune systems.

Oct 03, 2015
Nik_2233, continued...

We vaccinate millions of people every year for influenza with vaccines which are minimally effective or simply not effective. The last two years the vaccines have been a waste of time and money. Yet we continue to have to deal with calls for mandatory influenza vaccinations.

The sickest I have ever been was in the '80s or thereabouts when the swine influenza scare was the rage and everyone was encouraged to get vaccinated. I did and got influenza from the vaccination. Then a month later, I caught influenza again when I was going around. Yes, I know that we no longer use live viruses -- except we do with the nasal vaccination for children which we apply a few centimeters from your child's brain.

We don't have reasonable policies for vaccinations and we use scare mongering and outright coercion to compel compliance.

Oct 04, 2015
Mr D, the BCG vaccination is against TB. It's one of the classics, and I've the arm-scar from the challenge to prove it. Go check. One snag is an intestinal parasite load may suppress immunity developing, hence oft-indifferent results as-is in '3rd World'...

And, you cannot get 'flu from the 'flu vaccination. Go check. What you *can* get is a mild immune response, aka '3 day flu' showing you had some prior immunity to one or more components of that mix.

Sadly, 'flu mutates rapidly, hence the H5N1 etc codes, and the lead time on 'flu vaccine brewing is non-trivial, so the 'best guess' for the mix may fall short. Also, you can get two strains at once, which may recombine to something new and nastier.

Still, partial immunity is better than several weeks flat on your back due raging fever then exhaustion. Been there, done that. The hallucinations were *interesting*.

Sadly, each time I caught the 'flu was a week or two before I was due to have my annual vaccination...

Oct 05, 2015
you cannot get 'flu from the 'flu vaccination.Go check.

Actually, you should go check. When the swine influenza scare was on in the '80s, the influenza vaccine was an attenuated live virus. You could get influenza from the vaccination and I did.

Today, the influenza vaccines do not contain attenuated viruses except the nasal vaccine which is recommended for children but may also be administered to adults.

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