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American Education Becomes Special Education

Oral Microbiota and Autism

Saliva kidsBy Teresa Conrick

I am a big believer that an altered gut microbiota is associated with autism spectrum disorders and so do many others.  Recently, a group of scientists reported that it may be possible to diagnose autism, not on behaviors, eye contact, or repetitive movements, but instead on SALIVA!

The growing evidence of gut bacterial, viral and fungal abnormalities as a key to autism,  is not a crazy concept.  To think that a MEDICAL test rather than simply an OBSERVATIONAL one, could show a BIOLOGICAL mechanism, would be helpful in diagnosing and treating autism. 

Here is that study: Alterations of oral microbiota distinguish children with autism spectrum disorders from healthy controls  

 ....we demonstrated that the salivary and dental microbiota of ASD patients were highly distinct from those of healthy individuals. Lower bacterial diversity was observed in ASD children compared to controls, especially in dental samples.....pathogens such as Haemophilus in saliva and Streptococcus in plaques showed significantly higher abundance in ASD patients, whereas commensals such as Prevotella, Selenomonas, Actinomyces, Porphyromonas, and Fusobacterium were reduced....The distinguishable bacteria were also correlated with clinical indices, reflecting disease severity and the oral health status

Available twin studies showed that environmental factors are more important than genetic predisposition6. Among such factors, microbial dysbiosis is of increasing interest, with accumulating reports in animal models and human epidemiologic studies linking disruptive alterations in the gut microbiota to ASD symptomology7,8,9,10,11,12. 

The enrolled ASD subjects were between 7 and 14 years of age, with no previous medical treatment (except for rehabilitation training) or antibiotic/antifungal use within 3 months of sample collection.  Stopping here to say that I wondered if antibiotics could affect the results, as the controls did not have antibiotics (or antifungals), so did some research and it looks like the oral microbiome is not altered like the gut when it comes to antibiotics.

ASD was associated with increased abundance rates of Streptococcus (FDR Q = 0.02 in plaques) and Haemophilus (FDR Q = 0.007 in saliva), and decreased rates of Prevotella(FDR Q = 0.009 in plaques), Selenomonas (FDR Q = 0.042 in plaques), Actinomyces (FDR Q = 0.002 in saliva), Porphyromonas (FDR Q = 0.03 in saliva), and Fusobacterium (FDR Q = 0.011 and 0.025 in plaques and saliva, respectively). ...

 ASD was not only associated with decreased richness of commensals, but also related to reduced mutual effects within these bacteria. Among these commensals, an interesting finding was the obvious reduction of Prevotellaceae co-occurrence network patterns in dental samples, including Prevotella and Alloprevotella clusters (Fig. 4b). In contrast, the OTUs in ASD groups formed smaller clusters and were less interconnected. Two ASD-enriched shared OTUs, including OTU139 (Rothia aeria) and OTU285 (Streptococcus mutans), and saliva-specific OTUs, i.e. OTU159, OTU189, and OTU361, which were all annotated to Haemophilus, were negatively correlated with control-enriched OTUs, suggesting unknown antagonistic or mutually exclusive relationships. Moreover, clusters containing 9 OTUs belonging to Actinomyces, Solobacterium, Alloprevotella, Leptotrichia, Peptostreptococcus and Peptostreptococcacea [XI][G-1], were all enriched in both salivary and dental samples from healthy controls but not in the ASD groups....A separation was found between control- and ASD-enriched OTUs based on ABC scores, which are used to preliminarily determine the severity of ASD27. Notably, most ASD-enriched phylotypes, such as Haemophilus sp. (OTU159, R = 0.445, p < 0.001) and Rothia aeria (OTU139, R = 0.381, P = 0.004), were positively correlated to the ABC score...

The family Prevotellaceae, including the genera Prevotella and Alloprevotella, also showed a relatively low abundance in children with ASD. This was evident in dental samples as demonstrated in the co-occurrence network (Fig. 4). In agreement with these findings, Finegold et al. recorded a depletion of Prevotella in the gut of autistic patients compared to sibling controls38.  Meanwhile, Kang et al. reported that Prevotella, as the most significantly altered genus between autistic and neurotypical subjects, decreases dramatically in abundance in stool samples from autistic patients12.   A low abundance of Prevotella was also detected in feces from patients with Parkinson’s disease and untreated Multiple Sclerosis, supporting the relevance of this bacterium in CNS disorders 40, 41.  Prevotella is a commensal microorganism in multiple human habitats, including the intestine and oral cavity; it does not only interact with the immune system but also plays a key role in degrading a broad spectrum of saccharides42,43.44.  Interestingly, it was reported that autistic children may have deficiencies in saccharide metabolism and impaired carbohydrate digestion36,45.  Prevotella species also have essential genes for the biosynthesis of vitamins44, which were reported to mitigate ASD symptoms46.47.  Future studies are warranted to further interrogate the role of Prevotellaceae, also evaluating its therapeutic potential for ASD.

This finding is interesting and pertinent for my daughter and probably many more as PANDAS , also on the rise, with or without an autism diagnosis, has its epicenter with STREP infections.  The authors here report : Another putative pathogen showing overgrowth in dental samples was Streptococcus, a potent immunogenic trigger that was reported to affect the risk of CNS dysfunction such as Tourette Syndrome (another neurodevelopmental illness), Sydenham chorea and bacterial meningitis 55,56.  Indeed, Streptococcus was recorded to cause neurological damage by producing neurotoxins such as streptomycin, streptodornase, and streptokinase57. Studies of the intestinal microbiota indicated that Streptococcus might be responsible for bacterial infection in Parkinson’s disease and liver cirrhosis, probably originating from the mouth57,58,59. This finding indicated that specific oral bacteria could invade the gut and subsequently influence remote organs.

Connecting some more dots here related to TREATMENT as we look at bacterial infections.  I recently reported this important and pertinent study.  STREPTOCOCCUS  seems to be an important factor in these increasing neuropsychiatric, medical disorders.  Knowing that it can be in both the gut and in saliva may help in treatments.

The conclusion of this saliva study - In the present study, the MIA ["microbial index of ASD"] diagnosis model based on oral microbial biomarkers was proposed and achieved 96.3% accuracy, showing a great potential for improved diagnostic sensitivity and specificity. Compared to the gut microbiota usually collected from feces or biopsies, the oral microbiota is easier to sample and potentially mirrors the ASD-associated microbiota profile in situ. 

To sum up - 

    • A new test to diagnose autism is being discussed based on saliva.
    • Research shows that the oral microbiome of those diagnosed with autism, seems to mirror the gut of those diagnosed with autism.  Both show many pathogenic bacteria and less beneficial bacteria.
    • Streptococcus bacteria showed up in "significantly higher abundance" in the ASD group.
    • Prevotella, a commensal microorganism found in both the intestine and oral cavity, is lacking in ASD individuals.
    • The more pathogens and less commensals indicated a more severe autism in the child based on an ABC score (Aberrant Behavior Checklist).

The importance of this type of research can't be stressed enough, in both diagnosing and treating individuals. As far as prevention, especially as we see the physical and emotional pain of severe autism , the studies are indeed showing that the influence of the microbiome on the human body is significant. Knowing the factors that can disturb the microbiome is then key, as it is known that both the typical age of an asd diagnosis and the age in which the gut microbiome is developed, do seem to overlap:

"Human microbial colonization begins at birth and continues to develop and modulate in species abundance for about 3 years, until the microbiota becomes adult-like. During the same time period, children experience significant developmental changes that influence their health status as well as their immune system....Modern changes in lifestyle, including improved sanitization, cesarean sections, antibiotic usage, and immunizations are among some of the factors that can shift the microbiota, and are being studied as potential drivers of the sudden increase in immune-mediated diseases in the developed world.....

Teresa Conrick is Science Editor for Age of Autism.


Angus Files

Cant get more natural..

Mother's science experiment comparing how breast milk and formula fight bacteria goes viral after it proves 'boobs are magical' - and sparks a furious debate

Pharma For Prison



In my biology course, we are learning a lot about genetics. What my teachers have stressed is that environment plays a bigger role than genetics when it comes to displaying traits. And, while I have not had the chance to ask specifics, what makes any scientist so sure that 'vaccines do not cause autism' and apply it so broadly? That is definitely does not fit with the information we are learning. As an example, how many of you know how a plant may be white in one soil, but yet turn pink in another soil? Or how temperature can skew the male and female ratio of a sea turtle? These are examples of how the environment can visibly play a part in the expression and/or determination of traits.

I would be curious to know if there might be a relationship with contact allegies, IgG and microbiotia.


Teresa -
This is great info! Aside from the vaccine connection, it makes me wonder if it could account for the random cases of parents saying their children's symptoms improved after switching to organic food. I can't fathom pesticides not affecting the mouth microbiome, even if antibiotic don't. Antibiotics get swallowed down without chewing, I think, maybe not affecting plaques & saliva as much.

I absolutely don't want to detract from the excellent discussion of the strep involvement, but !!!! when they are referring to Haemophilus, what's up with that? According to medline:
"Haemophilus is the name of a group of bacteria. There are several types of Haemophilus. They can cause different types of illnesses involving breathing, bones and joints, and the nervous system.

One common type, Hib (Haemophilus influenzae type b), causes serious disease. It usually strikes children under 5 years old. Your child can get Hib disease by being around other children or adults who may have the bacteria and not know it. The germs spread from person to person. If the germs stay in the child's nose and throat, the child probably will not get sick. But sometimes the germs spread into the lungs or the bloodstream, and then Hib can cause serious problems such as meningitis and pneumonia.

Treatment is with antibiotics. There is a vaccine to prevent Hib disease."

Have they typed it? Was it b type? Is it wild type or vaccine strain, given the age of the children tested, they would have been vaccinated for that, no? Given that we know certain children can't seem to "clear" vaccine strains from the body after vaccination, as seen in measles in guts, bordatella in dogs for instance, viral shedding after flu vaccines, etc . . . is this indicating the Hib vaccine may be significantly contributing to the onset of autism symptoms?

I sense a promising new direction for the future of gynecology and obstetrics here. Because couldn't the microbiome in the vagina contribute good information here? How easy would it be to swab women at the same time they are getting their PAP test? It certainly raises some excellent questions:
How does the vaginal microbiome contribute to dna expression in the womb?
Can improving the vaginal microbiome prior to pregnancy improve health outcomes in children?
Does the vaginal microbiome shift in response to a transvaginal ultrasound during pregnancy?
Are toxins, whether injected or ingested, excreted at all in the vagina or uterine lining, and if yes, how does that affect their microbiome balances? (i.e. we used to think the placenta was a foolproof barrier, until we found out different)
What do pitocin and epidural chemicals during delivery do to the vaginal microbiome and their chemical secretions?
Does the oral microbiome of children match the microbiome found in the appendix, since the vaginal microbiome contributes to early oral microbiome exposure?
Could the vaginal microbiome, and thus also the oral microbiome, be affecting the expression of testosterone or estrogen both in utero and postnatally, affecting susceptibility to toxins?

To john -- Teresa  Conrick

Thanks for all of your comments.

john - People get can get their gut bacteria checked. Here are some sites and more developing I am sure-

Regarding breast milk -


Formula does produce a very different microbiome than human milk. The former is dead (although these days may have added probiotics), that latter has almost as many live cells as blood, and is loaded with beneficial bacteria. Many other differences where human milk develops all organ systems. Benefits last through one's life. One should only formula feed if there is absolutely no other choice.

Grace Green

I don't agree that without autistic behaviour there is no autism. Your argument is circular, because that is just the definition we have at the moment. For example, many fewer females are currently diagnosed with autism, and when they are they're usually at the severe end of the spectrum. Some believe this is because girls' behaviour is already different because they're girls. They, like me, may be experience all the internal symptoms fo vaccine injury/mercury poisoning but not showing it in their behaviour because society has a greater expectation of our good behaviour. This research is very promising in giving us an objective test for autism.

Angus Files

John I remember when we looked into it we seen an article from Mercola but on checking hes updated it as below

And then recently Prof Exley who were paying attention to now as we were more mercury driven in the past and were following his high silica content waters for aluminium removal.

The gut there are loads of tests for and various practitioners who can help with testing.Along the lines of the site below although I haven't used the site but its the sort of advise I have had from various practitioners over the past 17 years...

Pharma For Prison



how does one get there gut bacteria tested? where can i learn more about this? any help would be appreciated, thanks


woundering if formula rather than breastmilk could mess with gut health? is there too much sugar in formula?

Angus Files

" Transplanting “good” bacteria to guts of autistic persons may only give a temporary benefit, if their poisoned tissues continue to release mercury to blood and gut. The only way to prevent it is to stop vaccinations with toxic vaccines. "

That`s what we have experienced with all our treatments a temporary gain then gone and all the treatments work on others.I`m not a scientist far from it but I have been of the mind for a year or two now that unless the body is free from the metals your just treading water,which is great,if you have a regressive diagnosis but we always wish for more.

Pharma For Prison


Teresa  Conrick


Not arguing but my post is on science- not what people want to dissect as science-

Your comment- "Most likely it is, but autism is defined by abnormal behavior which obviously is determined by many pathobiological factors. You can’t randomly take a group of people, test their microbiota and decide based on the results who is autistic."

Actually, what happens in the gut from the pathogens cause those behaviors---- and yes, the point of this study is to distinguish the autism behaviors from the gut bacteria the children have - so yes, who develops autism or is "autistic."


@ Teresa,
I am not arguing the fact that microbiota is altered in autism. Most likely it is, but autism is defined by abnormal behavior which obviously is determined by many pathobiological factors. You can’t randomly take a group of people, test their microbiota and decide based on the results who is autistic. Without autistic behavior there no autism. I think most important question is - how vaccines full of toxins dramatically change human physiology and cause various pathologies, including pathological microbiota. I believe mercury from vaccines in the gut and liver kills certain types of sensitive bacteria, allowing colonization of the gut with mercury resistant bacteria. Transplanting “good” bacteria to guts of autistic persons may only give a temporary benefit, if their poisoned tissues continue to release mercury to blood and gut. The only way to prevent it is to stop vaccinations with toxic vaccines.

Angus Files

Great article Teresa very much appreciated. Wouldn’t it be great if they did a test before Pharma interference with vaccines etc of the babies and saliva after vaccination test? Then we could see how the gut has been destroyed. I suppose we could expand to all vaccinations, saliva before and saliva after. The HPV would interest me .Young girls going for it should insist on a before and after test surely government’s would agree after all they have nothing to hide, just ask Chop (below)….

Also gratefully forwarded to me by a friend today,another test below.Again saliva before and after above applies.
“New test can detect autism in children, scientists say
Blood and urine test, believed to be first of its kind, could lead to earlier diagnosis of autism spectrum disorders”

Pharma For Prison



I also think the evidence is solidifying regarding the role that vaccines play in autism. Rather than focusing on the cumulative effect of mercury and/or aluminum, I think it makes much more sense to focus on the TIMING of exposure. Very small amounts of thimerosal, if delivered to the infant during pregnancy or in the first seven months of life, would put males in particular at great risk, because of the testosterone surge that takes place in male infants during that time period. It is conceivable that 25 mcg of mercury, in combination with a total testosterone of 400 in males, which they can achieve during their "mini-puberty" during the first seven months of life, could be the equivalent of getting large doses of many different types of antibiotics simultaneously -- effectively poisoning the microbiome from that point forward. So, I hope that researchers will begin to focus more on the timing of these poisons, rather than just the cumulative totals. I call this the 3Ts of mercury poisoning: Timing, Type, Testosterone.

Teresa  Conrick

"Autism can't be diagnosed based on microbiota"-

No Vac- I disagree. That is the point of this article and what the science has been increasingly showing for years. The microbiome IS being changed, damaged and yes, vaccination is being reported and studied for that.

Why do so many people not seem to understand that the gut can cause brain damage.......

"here is a growing emphasis on the relationship between the complexity and diversity of the microorganisms that inhabit our gut (human gastrointestinal microbiota) and health/disease, including brain health and disorders of the central nervous system. The microbiota-gut-brain axis is a dynamic matrix of tissues and organs including the brain, ......
"Aberrant regulation of neuroendocrine, and immune responses are believed to play a key role in the precipitation, maintenance, and/or exacerbation of a number of neuroinflammatory- and stress-related disorders including anxiety, depression, Alzheimer's disease, multiple sclerosis, arthritis and autism amongst others......a delicate balance between pro-inflammatory or anti-inflammatory alterations needs to be tightly regulated, as an uncontrolled and sustained response can have significant inflammatory collateral damage and detrimental effects on mood and behaviour....chronic, dysregulated activation of microglia can lead to increased inflammatory tone ultimately resulting in malfunction and damage of brain cells.


And as the study that Teresa linked to here shows, fecal transplants appear to offer the greatest hope for curing all of these conditions.


Thank you for this post, Teresa. I am following this line of research with great interest. Scientists have observed the same thing with schizophrenics:


Vaccines contain mercury, aluminum and many other toxic metals, including nanoparticles, antibiotics, detergents and plethora of microbial and viral material, which can easily alter the microbiota in a vaccinated person. Since mercury and probably other metals stay in different tissues for years or decades they will permanently alter the microbiota. IMO, this is a secondary effect to child poisoning with toxic vaccines. Autism can't be diagnosed based on microbiota (it would be nonspecific), it must always be diagnosed based on behavioral observations, although doing additional testing for microbiota certainly won't harm and may aid the treatment. Vaccines are multifactorial poisons and remember - no vaccines no autism.

Teresa  Conrick


Not sure what you are asking? Are vaccines capable of causing autism?

John Stone


As a medical person you ought to be able to understand that medical interventions can have many unintended consequences including disrupting the gut. Autistic people have neurological impairment, they have a complex of GI problems, but I am not sure how that would absolve vaccines necessarily from being a catalyst. Your non-sarcastic comment the other day was very welcome (if it was non-sarcastic).

Frederic Chopin

I thought it was vaccines.


Finally! Love this article, great study. However, because the colonies complete their growth and are adult-like by 3 years of age, does that mean that this can't be "fixed" in children older than 3? Would love to know. Thank you!

bob moffit

"The growing evidence of gut bacterial, viral and fungal abnormalities as a key to autism, is not a crazy concept. To think that a MEDICAL test rather than simply an OBSERVATIONAL one, could show a BIOLOGICAL mechanism, would be helpful in diagnosing and treating autism."

Just curious .. would it be implausible to "think that a MEDICAL test rather than simply an OBSERVATIONAL one could show a BIOLOGICAL mechanism that would be helpful in diagnosing and treating impaired mental health?

Is anyone going to conduct medical tests on the latest school shooter in Florida .. to ascertain if he shows obvious evidence of "gut bacterial, viral and fungal abnormalities" as a key to understanding his mental health behaviors?

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