Measles, mumps, rubella vaccine, inflammatory bowel disease and autism
MMR is a combination vaccine that protects against measles, mumps, and
rubella (German measles). It is given to children at 12 months and again
at 4 years of age. A link between the MMR vaccine and development of bowel
inflammation (IBD) and autism has been suggested by some researchers.
However, numerous carefully performed studies and reviews have now been
done that have found no relationship between MMR vaccine and autism or
IBD.
This fact sheet answers the following commonly asked questions. More general
information on the MMR vaccine is also available by following the links
in Further reading below.
• What is the MMR vaccine?
• What is autism and what is inflammatory bowel disease
(IBD)?
• Does the MMR vaccine cause autism and why was this
suggested?
• What about the studies that suggested a link between
MMR and IBD /autism?
• What studies show that autism and IBD are not related
to the MMR vaccine?
• What have expert reviews concluded?
• Is there any benefit in giving each of the component
vaccines separately?
• What about reports of a link between autism and thiomersal
(a preservative in some vaccines)?
• Further reading
What is MMR vaccine?
Measles, mumps, rubella (MMR) vaccine is a live virus vaccine that contains
measles, mumps and rubella viruses that have been modified (or attenuated)
to produce an immune response that protects children against natural infection
without causing the diseases themselves. The Australian National Health
& Medical Research Council (NHMRC) recommends MMR for all children
at 12 months of age and again at 4 years of age.
Since the introduction of vaccination against these diseases, measles,
mumps and rubella have become rare in Australia. However, it is extremely
important that children continue to be immunized because these diseases
remain very common in other parts of the world, and even slight decreases
in the number of immunized children can result in major epidemics of measles,
mumps or rubella (including the congenital rubella syndrome which seriously
affects unborn children).
What is autism and what is inflammatory bowel
disease (IBD)?
Autism is a disorder of normal development that is usually diagnosed between
18 months and three years of age. Children and adults with autism typically
have difficulties in verbal and non-verbal communication, social interactions,
and leisure or play activities. Autism is four times more common in boys
than girls and occurs in all racial and social groups. Many children have
some of the features of autism but do not have all the diagnostic criteria
in which case terms such as Pervasive Developmental Disorder (PDD) and
Autism Spectrum Disorder (ASD) are used. A single cause of autism has
not been identified, but current research links it to developmental, genetic
and environmental factors.
IBD is a group of chronic inflammatory disorders of the small and large
bowel, the commonest being ulcerative colitis and Crohn's disease. IBD
is relatively rare, and usually occurs between 15 to 30 years, but can
also occur in children. Common symptoms include diarrhoea, fever, stomach
pain and weight loss. The cause of IBD is not understood, but immune mechanisms
and a genetic predisposition are likely involved.
Does the MMR vaccine cause autism or IBD, and why was this suggested?
Numerous studies and expert panel reviews that have concluded that there
is no link between MMR vaccine and autism or IBD.
The possibility of a link between the MMR vaccine and autism/IBD was suggested
primarily by one group of researchers led by Dr Andrew Wakefield in the
United Kingdom. Dr Wakefield’s studies suggested that measles virus
in the gut caused a new syndrome of IBD which resulted in decreased absorption
of essential vitamins and nutrients through the intestinal tract. It was
suggested that this in turn caused developmental disorders such as autism,
or worsening of symptoms in children already diagnosed with autism, so-called
“regressive autism”. Although this theory generated a lot
of media attention, the studies on which it is based have many significant
weaknesses. Over 20 subsequent studies and many expert reviews that have
shown no association between MMR and these diseases (see below).
What about the studies that suggested
a link between MMR and IBD /autism?
Medical and scientific experts who have reviewed the few studies suggesting
a relationship between measles or MMR vaccine and autism/IBD have found
them to have many significant weaknesses.
In 1993 the first of Dr Wakefield’s studies suggested an association
between both the natural and vaccine types of measles virus and IBD based
on a study of bowel specimens from children with IBD. However, other groups
of researchers using sensitive laboratory methods have shown that there
is no evidence of measles virus in the blood or bowel of children with
IBD. In 1998 Dr Wakefield and others reported 12 children with an apparently
new syndrome of IBD in association with developmental disorders like autism.
However, this study was conducted on highly selected patients, and there
were too few patients and no control patients. These errors significantly
affected the credibility of the study findings. If IBD causes autism,
IBD would be expected to occur first, however, in at least 4 cases, autism
preceded the bowel symptoms, and in most of the other cases the date of
onset of bowel symptoms was unknown.
In 2002 Uhlmann, Wakefield and others published a study showing a higher
rate of measles virus in the bowel of autistic children with bowel symptoms,
compared to a group of children without autism. However, key information
on the characteristics and the method of selection of the cases and control
patients, on vaccination status, and on laboratory methods were not given,
and the control subjects were not matched for gender or age.
In 2004, 10 of the original 13 authors of Dr Wakefield’s 1998 study
published a statement retracting the paper's interpretation, stating that
the data were insufficient to establish a causal link between MMR vaccine
and autism.
What studies show that autism and IBD
are not related to the MMR vaccine?
A large number of independent researchers from around the world, using
many different techniques ranging from molecular biology studies to population
based epidemiology, have now shown that there is no evidence of a link
between MMR vaccine and autism or IBD.
The following are summaries of some of the studies performed:
• In 1999, a large population-based study in England looked at the
vaccination status of 498 children with autism and control subjects without
autism and found no link between the timing of vaccination with MMR and
the onset of autism.
• In 2004 another English study looked at the rates of autism in
5,500 children who attended GPs and were immunized with MMR, and found
no evidence to suggest a link between the vaccine and autism.
• A study of more than 440,000 Danish children vaccinated in the
1990's compared with 96,000 unvaccinated children provided strong evidence
against the hypothesis that MMR causes autism or autistic spectrum disorder.
• A large study in Finland followed almost 600,000 children for
20 years after MMR vaccination and found no evidence for MMR vaccine-associated
autism or other neurological disorders.
• A study of the rates of IBD and autism among 6100 French school-aged
children found no association between MMR and these diseases.
• A study in Sweden in 1998 looking at the prevalence of autism
over 10 years found no change after the introduction of MMR vaccine.
• Two independent groups of researchers in the UK performed epidemiologic
studies to determine if there was an association between bowel symptoms
/autism, and MMR. Both studies found no evidence for gastrointestinal
problems being linked to developmental regression or to MMR vaccination.
• Additional studies in the US and UK found no correlation between
trends in early childhood MMR immunisation rates and trends in autism
diagnosis. For example, a study done in California, showed that although
rates of autism have gone up by 373% over 15 years, the increase in the
number of children immunized with MMR has only increased by 14% in that
time.
• A study in the United States looked at patients with IBD born
over a 32 year period, found that vaccination with MMR or other measles-containing
vaccines, or the timing of vaccination early in life, did not increase
the risk for IBD.
• At least 3 laboratory-based studies by different research groups
using technical methods similar to those in the Uhlmann study, found no
evidence of measles virus in the bowel specimens of patients with IBD.
What have expert reviews concluded?
A review by the World Health Organization concluded that current scientific
data do not permit a causal link to be drawn between the measles virus
and autism or IBD. An extensive review published in 2004 by the Institute
of Medicine, an independent expert body in the United States, has concluded
that there is no association between the MMR vaccine and the development
of autism.
Reviews by the American Academy of Pediatrics, The British Chief Medical
Officer, the UK Medical Research Council, Canadian experts, and numerous
other scientific experts have stated that there is there is no link between
autism or IBD and the measles vaccine.
Is there any benefit in giving each of the vaccine
components separately?
No, there is no evidence that giving each vaccine component of MMR separately
over time is of any benefit. In fact, giving each component separately
may be harmful because children and their contacts would be exposed to
serious diseases over a longer period of time. In addition, many extra
needles and immunisation visits would be required. National and international
expert bodies, including the NHMRC, the World Health Organization, the
Institute of Medicine, the American Academy of Pediatrics, and The United
Kingdom Department of Health all recommend that MMR should continue to
be used. At present, only the rubella vaccine is available separately
in Australia; it is given to women of child-bearing age who are susceptible
to rubella, to prevent the Congenital Rubella Syndrome.
One of the serious consequences of a decrease in the number of children
immunized with MMR vaccine is an increase in the number of children and
susceptible adults who will get rubella (German measles). Rubella infection
of susceptible women during pregnancy can cause the Congenital Rubella
Syndrome in the developing fetus, which may result in miscarriage, brain
damage, blindness, deafness and other serious problems, including autism
spectrum disorder.
What about reports of a link between autism
and thiomersal (a preservative in some vaccines)?
Thiomersal (also known as thimerosal) is a preservative used in some vaccines
to prevent bacterial contamination of the vaccine vial. Since it is a
mercury-based substance, theoretical concerns regarding its use in vaccines
have been raised, and it has been removed from many vaccines as a precautionary
measure. However, all the scientific evidence available to date suggests
that thimerosal in vaccines has never caused any harm. Although a study
published by Geier and Geier in 2003 suggested links between thiomersal
in vaccines and the rates of autism and heart disease in the United States,
these findings have been dismissed because of numerous errors in the study’s
methods. A recent review published in the journal Pediatrics assessed
all the published studies regarding thiomersal and autism and concluded
that there was no link between thiomersal-containing vaccines and autism
spectrum disorder. The Institute of Medicine recently conducted a wide
ranging expert review that concluded that there is no link between thiomersal
in vaccines and autism.
MMR vaccine does not contain thiomersal, and has never contained thiomersal.
For further information on vaccines and thiomersal see the NCIRS Thiomersal
Fact Sheet. (link).
Further reading
More general information regarding the MMR vaccine is available for immunisation
providers online from the Australian Immunisation Handbook,
found here,
and for parents at the Immunisation Website of the Australian Government
Department of Health found here.
This editorial in the Medical Journal of Australia also discusses MMR, autism and inflammatory bowel disease.
Additional Web-based information
1. Institute of Medicine. Press Release: MMR Vaccine and Thimerosal-Containing
Vaccines Are Not Associated With Autism. May18, 2004. Link
(accessed October 09, 2008).
2. Does MMR vaccine cause autism? Examine the evidence. Immunisation Action
Coalition. Link. (accessed
November 22, 2004).
3. MMR The Facts, The United Kingdom. Link
(accessed November 22, 2004).
4. United Kingdom Immunisation Information website. Link
(accessed November 22, 2004).
5. Vaccines and autism theory. Centers for Disease Control and Prevention.
Link. (accessed
November 22, 2004).
6. Inflammatory Bowel Disease (IBD) and vaccines. Link
(accessed November 22, 2004).
7. World Health Organisation Web site. Link.
(accessed November 22, 2004).
8. Commonwealth Department of Health and Aged Care. Immunisation myths
and realities: responding to arguments against immunisation. 4th ed. Canberra:
Australian Government Publishing Service, 2007. Link.
(accessed October 09, 2008)
Scientific papers
9. Smeeth L, Cook C, Fombonne E, Heavey L, Rodrigues LC, Smith PG, Hall
AJ. MMR vaccination and pervasive developmental disorders: a case-control
study. Lancet. 2004 Sep 11;364(9438):963-9.
10. Chen, W, Landau, S. Sham, P, and Fombonne, E. No evidence for links
between autism, MMR and measles virus. Psychological Medicine, 2004. 34:543-553
11. Parker SK, Schwartz B, Todd J, Pickering LK. Thimerosal-containing
vaccines and autistic spectrum disorder: a critical review of published
original data. Pediatrics. 2004 Sep;114(3):793-804.
12. Offit PA, Coffin SE. Communicating Science to the Public: MMR Vaccine
and Autism Vaccine, December 8, 2003, Vol. 22(1):1-6
13. Wilson K, Mills E, Ross C, et al. Association of autistic spectrum
disorder and the measles, mumps and rubella vaccine. A systematic review
of current epidemiological evidence. Archives of Pediatrics and Adolescent
Medicine 2003;157:628-634.
14. Madsen KM, Hviid A, Vestergaard M, et al. A population-based study
of measles, mumps, and rubella vaccination and autism. New England Journal
of Medicine 2002;347:1477-82.
15. Taylor B, Miller E, Lingam R, et al. Measles, mumps, and rubella vaccination
and bowel problems or developmental regression in children with autism:
population study. British Medical Journal 2002; 324:393-6.
16. Andrews N, Miller E, Taylor B, et al. Recall bias, MMR, and autism.
Archives of Disease in Childhood 2002;87:493-4.
17. Mäkelä A, Nuorti P, Peltola H. Neurologic disorders after
measles-mumps-rubella vaccination. Pediatrics 2002;110:957-63.
18. Uhlmann V, Martin CM, Sheils O, et al. Potential viral pathogenic
mechanism for new variant inflammatory bowel disease. Molecular Pathology
2002;55:84-90.
19. Kaye JA, del Mar Melero-Montes M, Jick H. Mumps, measles, and rubella
vaccine and the incidence of autism recorded by general practitioners:
a time trend analysis. British Medical Journal 2001;322:460-3. Link.
(accessed September 29, 2004)
20. Fombonne E, Chakrabarti S. No evidence for a new variant of measles-mumps-rubella-induced
autism. Pediatrics 2001;108:58-9
21. Dales L, Hammer SJ, Smith NJ. Time trends in autism and in MMR immunization
coverage in California. Journal of the American Medical Association 2001;
285:1183-5.
22. Iizuka M, Chiba M, Yukawa M, Nakagomi T, Fukushima T, Watanabe S,
Nakagomi O. Immunohistochemical analysis of the distribution of measles
related antigen in the intestinal mucosa in inflammatory bowel disease.
Gut. 2000 Feb 46(2):163-9.
23. Patja A, Davidkin I, Kurki T, Kallio MJ, Valle M, Peltola H. Serious
adverse events after measles-mumps-rubella vaccination during a fourteen-year
prospective follow-up. Pediatric Infectious Disease Journal 2000;19:1127-34.
24. DeStefano F, Chen RT. Autism and measles, mumps, and rubella vaccine:
No epidemiological evidence for a causal association. Journal of Pediatrics
2000; 136:125-126.
25. Taylor B, Miller E, Farrington CP, et al. Autism and measles, mumps,
and rubella vaccine: no epidemiological evidence for a causal association.
Lancet 1999;353:2026-9.
26. Peltola H, Patja A, Leinikki P, Valle M, Davidkin I, Paunio M. No
evidence for measles, mumps, and rubella vaccine-associated inflammatory
bowel disease or autism in a 14-year prospective study. Lancet. 1998 May
2;351(9112):1327-8.
27. Wakefield AJ, Murch SH, Anthony A, et al. Ileal-lymphoid-nodular hyperplasia,
non-specific colitis, and pervasive developmental disorder in children.
Lancet 1998;351:637-41.
28. Feeney M, Ciegg A, Winwood P, Snook J. A case-control study of measles
vaccination and inflammatory bowel disease. The East Dorset Gastroenterology
Group. Lancet 1997;350:764-6.
29. Fombonne E, Du Mazauabrun C, Cans C, Grandjean H. Autism and associated
medical disorders in a French epidemiological survey. Am Acad Child Adolesc
Psychiatry 1997;36:1561-9.
30. Haga Y, Funakoshi O, Kuroe K, et al. Absence of measles viral genomic
sequence in intestinal tissues from Crohn's disease by nested polymerase
chain reaction. Gut 1996;38:211-5.
This document was prepared by the National Centre for Immunisation Research
and Surveillance of Vaccine Preventable Diseases. Updated November, 2004
This document was written by A/Professor Raina
MacIntyre, Dr Kristine Macartney and A/Professor Peter McIntyre of the
National Centre for Immunisation Research and Surveillance of Vaccine
Preventable Diseases.
Updated 23 November 2004