fourteen studies


Quick History

The Right Question

The "14" Studies

Studies Ranked

Our Studies

Good Guys, Bad Guys

Now What?


About Us Study Analysis

"Lack of Association Between Measles Virus Vaccine and Autism with Enteropathy: A Case-Control Study"
PLoS One, Mady Hornig, Thomas Briese T, et al. (September 2008)


This study is intended to refute the Wakefield study mentioned above. However, it made one critical distinction from the Wakefield approach: it didn’t recruit for the subset of children with autism who regressed after MMR vaccination. That, combined with a very small sample size, renders the results nearly meaningless. At least the study concedes that children with autism suffer from gastrointestinal issues.

Actual Question This Study Asked & Answered:

Q: Do children with autism have a persistent measles virus RNA in their gastrointestinal tract [which they got from their MMR vaccine]?

A: No

Did the study look at unvaccinated children?


Conflict of Interest:

"This work was supported by CDC grant U50 CCU522351 to AAP [American Academy of Pediatrics] and by National Institutes of Health awards AI57158 (Northeast Biodefense Center-Lipkin), HL083850, and NS47537.

Role of Study Sponsors: Members of the funding organization (AAP) and its sponsor (CDC) participated along with experts in virology and neurovirology, autism pathogenesis, and vaccine design and safety; representatives of the autism advocacy community; and study collaborators in an Oversight Committee that reviewed and agreed to all aspects of study design prior to data collection."

Meaning: The CDC is in charge of the US vaccine program and engineered the study.

Ability to Generalize:

Per the above, the study only looked at 25 children with autism, and didn't screen those cases by children who had regressed after MMR vaccine. So, none whatsoever.

Post-Publication Criticism:

Very high, because the methodology of the study nearly guaranteed the outcome.

Scoring (Out of 40 possible points):

Asked the Right Question: 0

Ability to Generalize: 0

Conflict of Interest: 0

Post-Publication Criticism: 1

Total Score: 1

Guest Critic #1: Thoughtful House, Dr. Andrew Wakefield

Autism Researchers Comment on New Study and Welcome the Affirmation of Previous Measles Findings

A study published yesterday in the Public Library of Science One (PLOS1), an on-line journal, failed to find evidence of measles virus in the intestinal tissue of 24 children with autistic regression and gastrointestinal symptoms. The findings contrast with those published in 2002 in which researchers from Ireland and the UK found measles in 75 of 91 biopsies from autistic children with GI inflammation, and in only 5 of 70 samples from non-autistic children(1). The children with autism in the 2002 study developed gastrointestinal symptoms and autistic regression after the MMR vaccine.

In the study published yesterday, conducted by three independent laboratories, only 5 of the 25 children developed these symptoms after the MMR vaccine and therefore, only these five are comparable to the 2002 study. This new study confirmed that results from the laboratory of Professor John O'Leary (one of the collaborators on the new study, and senior author of the 2002 study) were correct, and identical to the results obtained by the laboratories of the Centers for Disease Control and Prevention (CDC) and Dr. Ian Lipkin of Columbia University.

In that this new study affirms the reliability of Professor O'Leary's laboratory and therefore of his previous findings, a major impact upon the current hearings in vaccine court is likely, wherein the government's defense relies largely on the claim that Professor O'Leary's finding of measles in the intestinal biopsy of Michelle Cedillo (a child with severe autism and epilepsy) was unreliable. The historical reliability of the measles assay used in Professor O'Leary's laboratory is now confirmed.

The authors of the PLOS1 study make the erroneous claim that epidemiological studies have not supported an MMR-autism link, when in fact the CDC's own study published in 2004 shows a significant association between autism and younger age at the time of MMR vaccination.(2)

We are pleased to see that this new study provides further confirmation that children with autism suffer from gastrointestinal problems that deserve to be addressed as a priority.

Dr. Andrew Wakefield, Executive Director of Thoughtful House Center for Children, whose work has focused on intestinal disease, and on the possible role of MMR vaccine in regressive autism in children with GI symptoms, welcomed these new findings. Dr. Wakefield was a co-author of the 2002 paper that, unlike yesterday's study, examined children in the majority of whom there was a clear temporal link between MMR exposure and regression. Dr. Wakefield comments, "The search for the 'footprints' of measles virus in the intestine is merited, based upon the previous findings and the intestinal disease that is commonly found in these children. This new study rules out only one possibility - that the measles virus must remain for the long term in the intestine. We need to consider that the MMR vaccine can cause autism as a hit-and-run injury, but not necessarily leave the measles virus behind."

While we welcome this study as a piece in the ever-growing body of evidence that illuminates the complexity of autism and the possible factors that cause it, it is clear that yesterday's study does not establish that the MMR vaccine is not associated with autism. This work examines one small part of a very complex equation, and in fact by affirming Professor O’Leary’s laboratory and assay methods, it inadvertently endorses the validity of his 2002 findings of vaccine-strain measles virus in the gut tissue of a group of children with autism.

Guest Critic #2: National Autism Association

CDC Misses Target With Flawed MMR/Autism Study
NAA says: Wrong Question Asked. Wrong Children Studied. Wrong Conclusions Reached.

Nixa, MO - A Centers for Disease Control and Prevention (CDC) study released today claims there is no link between the MMR vaccine and autism. The National Autism Association (NAA) says this study does nothing to dispel the growing public concern over a vaccine-autism connection and raises several questions concerning design and methodology.

For years, parents have claimed that MMR triggered their child’s subsequent GI (gastrointestinal) disease and autism. In a 2002 paper where the majority of autistic children were found to have measles in their intestines, the children examined showed a clear temporal link between MMR exposure and regression. The CDC's attempt to replicate the 2002 study fell far short of proving the safety of the MMR vaccine.

  • The CDC study was designed to detect persistent measles virus in autistic children with GI problems. The assumption being if there is no measles virus at the long delayed time of biopsy, there is no link between autism and MMR. But NAA says this underlying assumption is wrong. The questions should have been: Do normally developing children meeting all milestones have an MMR shot, develop GI problems and then regress into autism? Do they have evidence of measles and disease in their colons compared to non-vaccinated age and sex matched controls?
  • In the current CDC study, only a small subgroup of children was the correct phenotype to study. From page 7, "Only 5 of 25 subjects (20%) had received MMR before the onset of GI complaints and had also had onset of GI episodes before the onset of AUT (P=0.03)." The other 20 autistic children in the study had GI problems but the pathology developed before the MMR vaccine. Additionally, the controls all received the MMR vaccine and had gastrointestinal symptoms. The controls should have been free of exposure to vaccine measles in order to make a comparison relevant for purposes of causation.
  • Inflammatory bowel disease in the absence of MMR RNA does not mean that MMR shot didn't precipitate the GI disease and didn't precipitate autism. A similar example would be rheumatic fever where the infection is cleared quickly but damage to the heart and/or brain last a lifetime.

Public confidence in the safety of vaccines is at risk until safety studies are performed that are required by law, ethics, and science. NAA calls for a vaccinated vs. non-vaccinated study comparing all health outcomes including autism. The CDC is in charge of vaccine safety, owns patents to vaccines (according to a UPI Investigative Report from 2003) and is in charge of promoting vaccines. The public should demand that vaccine safety be taken away from an agency with such conflicts and support HR#1973, the Vaccine Safety and Public Confidence Assurance Act.

Guest Critic #3: SafeMinds

SafeMinds Statement on Measles Virus and Autism Study

A scientific study released today examined the hypothesis that measles virus persisting in the intestinal tract from the MMR vaccine causes or exacerbates autism. The study refuted this hypothesis for the majority of autism cases while validating the link between gastrointestinal (GI) disease, inflammation and autistic regression. The study design precluded assessment of a role for acute measles infection from MMR in a subset of children with autism and did not examine the role of other vaccines, vaccine components such as thimerosal, or other environmental exposures which can trigger gastrointestinal and immunological problems. The topic is of public health interest due to the increasing autism epidemic and parent and scientific reports connecting mercury and vaccines, including MMR, with autism onset.

The study, "Lack of an association between measles virus vaccine and autism with enteropathy: a case-control study" by Mady Hornig and colleagues, appears in this month's PloS One journal. Colon biopsies from 38 children presenting with gastrointestinal disorder, 25 with autism and 13 without neurological differences, were examined for presence of measles virus RNA by three laboratories to ensure validity. All children had been given the MMR vaccine when younger, and except for one subject, the vaccine was given more than 6 months prior to the biopsy, in order to determine persistence. The MMR is a live virus vaccine and failure to clear the attenuated measles virus is a known but rare occurrence after vaccination.

The persistent measles and autism hypothesis, linking bowel disease, autistic regression and MMR, was originally made by Andrew Wakefield and colleagues in 1998. One of the three labs involved in the Hornig study was led by John O'Leary who conducted the testing for the Wakefield study. The three Hornig study labs validated each other, confirming the rigorousness of Dr. O'Leary's work. Dr. O'Leary conducted the testing for one of the autism test cases now in the Federal Court for Vaccine Claims. The child, who regressed into autism and bowel disease after receiving the MMR, tested positive for measles virus. The Hornig study also substantiates the link between autistic regression and gastrointestinal disorder.

The Hornig study found only one autism patient with persistent measles virus. None was detected in the remaining 24 children. This finding differs from the Wakefield and more recent studies which reported a high percentage of children with regressive autism and bowel disease with detectable measles virus. The discrepancy was not explained but may be due to how and when the biopsies were taken or differences in the study samples.

The Hornig findings suggest that persistence may not be a factor but inadequately address whether measles vaccination may lead to an acute reaction that contributes to dysfunction. An acute or 'hit and run' mechanism means that the initial effect occurs and the virus is rapidly cleared. The effect would not require persistence and is how many biological disturbances arise from pathogens and toxins. The study sample was small, making characterization of subgroups difficult. Autism is considered a complex and heterogeneous disorder with multiple, interacting causal and exacerbating factors. The MMR vaccine may have led to dysfunction in a subset of children and other triggers may underlie other cases. While half the autism cases in the study had gastrointestinal or autism symptoms prior to receipt of the MMR, additional triggers such as other vaccines or environmental pollutants acting on the majority of cases would effectively wash out a positive MMR-autism association in a subset.

Larger studies are needed to tease out the role of the various contributors to autism onset and severity of symptoms, including GI problems. These studies need to examine multiple factors, not just one. In particular, a comparison of health outcomes in vaccinated and unvaccinated populations is warranted. The Hornig study has advanced our understanding of gastrointestinal inflammation and autism and casts doubt on measles persistence in most children with autism, but it does not rule out an acute MMR effect in a subset and does not absolve multiple vaccinations or mercury from playing a role in autism.

Guest Critic #4: CryShame



A new study by Hornig1 et al, which revisits the MMR – autism controversy, has failed to find measles virus in the bowel of autistic children, so contradicting Wakefield and O'Leary's earlier finding of measles virus in autistic children.2 The latest study fails to find a link between MMR vaccine and autism.

However the study inadvertently gives credence to Wakefield and O'Leary's previous work on measles virus and validates their earlier findings. It also substantiates the link between autistic regression and gastrointestinal disorder reported by Wakefield in his 1998 Lancet article.3

Whereas Wakefield and O'Leary in 2002 looked at bowel biopsies of 91 children whose autism and bowel disease followed the MMR vaccination, Hornig et al examined biopsies of only 5 children who had MMR before the onset of these symptoms. The remaining 20 children had MMR after onset. This is a very small sample from which to conclude that there is no link between MMR, autism and bowel disease. It is substantially smaller than Wakefield's earlier study.

Importantly, the centres that analysed the bowel biopsies arrived at similar findings despite blinded procedures - i.e. none of them knew which biopsies they were examining. One of these centres was that of Professor John O'Leary. Professor O'Leary found measles virus in the bowel of 75 children out of 91 in the earlier 2002 study and is a joint author of the present Hornig study, which used the same methods of analysis as O'Leary had used in 2002. The consistency of the findings between the three centres confirms the validity of O'Leary's methods - the same methods used in 2002 - and the accuracy of his finding of measles virus.

In the US, the government is the defendant in a key case before the Federal Court for Vaccine Claims brought by 5000 children, many autistic, claiming vaccine damage. In a lead case, Michelle Cedillo, who regressed into autism and bowel disease after receiving the MMR, was tested positive for measles virus by O'Leary. The new study substantially strengthens Cedillo's case.

Parents of autistic children want to know why their children suffer from these lifetime debilitating illnesses. In the 10 years since Wakefield's 1998 Lancet paper was published, there has been no proper attempt to replicate his studies. In the UK there is currently no research into the autism and bowel disease which is estimated to affect about half the children. Although autism is the largest and fastest growing developmental condition among UK children - affecting at least one in a hundred children - the government spends no more than 1 million pounds a year on autism research. How long before the government faces up to the epidemic proportions of this increasingly prevalent condition and to its cost on children, families and society?

Instead of addressing the causes of these illnesses, the government has enveloped a culture of fear around autism/bowel disease research. It is worthy of note that the study published this week reports clinical procedures and a study design which, here in the UK, has resulted in three doctors being accused of what amounts to child abuse. Whilst Wakefield, Murch and Walker-Smith have been subjected to a disgraceful attempt to discredit and publicly shame them, Hornig et al. are able to carry out these same procedures, at the behest of the CDC , and report their findings freely with no repercussions whatsoever. Are we to assume they will be hauled before their respective professional councils - or does that only happen if the results threaten the vaccination programme? The culture of fear engendered in the UK has meant that medical scientists refuse to address the issue, whilst our children suffer intolerable levels of pain and a future with no hope. It is contemptible.