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Controversy MMR Vacsine that Cause Autism
JUNIANI NIANDINI
030.08.133
JAKARTA, 14 JUL 2011
TRISAKTI UNIVERSITY of MEDICINE
Contents :
Contents .......................................................................................................................ii
Abstract ........................................................................................................................1
Introduction ..................................................................................................................2
MMR Vaccine...............................................................................................................3
Autism...........................................................................................................................5
Controversy MMR Vacsine that Cause Autism............................................................8
Conclusion ..................................................................................................................14
References ..................................................................................................................15
Abstract
The publication of Dr. Wakefield’s study in 1998, along with profuse media coverage
of immunizations and Autism, has lead to an enormous amount of research studies examining
whether a link between the MMR vaccination and Autism actually exists but One
populational study, centered in Yokohama, Japan in 2005, is heralded as one of the most
decisive studies proving no connection between the MMR vaccine and Autism. Particularly,
this study examined the rate of development of Autism Spectrum Disorders (ASD) during an
MMR vaccination program and after the MMR vaccination program had been discontinued
Although child vaccination rates remain high, some parental concern persists that
vaccines might cause autism. Three specific hypotheses have been proposed: (1) the
combination measles-mumps-rubella vaccine causes autism by damaging the intestinal lining,
which allows the entrance of encephalopathic proteins; (2) thimerosal, an ethylmercury-
containing preservative in some vaccines, is toxic to the central nervous system; and (3) the
simultaneous administration of multiple vaccines overwhelms or weakens the immune
system. We will discuss the genesis of each of these theories and review the relevant
epidemiological evidence.
Introduction
The MMR vaccine controversy refers to claims that autism is caused by the MMR
vaccine against measles, mumps, and rubella. Particularly, the childhood Measles, Mumps
and Rubella (MMR) vaccine has been connected to the appearance of Autism in children, and
has led to the formation of anti-vaccination groups and increased rates of vaccination
exemption within schools. The scientific consensus is that no credible scientific evidence
links the vaccine to autism, and that the vaccine's benefits greatly outweigh its risks.
Claims of a connection between the vaccine and autism were initially raised in a 1998
paper in the respected British medical journal The Lancet. After it was discovered that
Andrew Wakefield, the paper's lead author, had received major funding from British trial
lawyers seeking evidence, ten of the paper's twelve coauthors retracted its interpretation of an
association between MMR vaccine and autism. Why are vaccinations such as the MMR
seemingly necessary? What are the popular beliefs driving the rejection of vaccines? Finally,
is there really a link between vaccinations and Autism? The following sections will review
both common information surrounding vaccinations and scientific research specifically
studying the correlation of the MMR vaccine and Autism.
MMR Vaccine
Vaccine
Firstly, vaccinations are preparations used as preventative measures to develop
immunity against a specific disease through the injection of an innocuous form of the disease
agent, or through injection of a weakened bacteria or virus to stimulate antibody production.
Vaccinations, according to the Centers for Disease Control and Prevention, are crucial in
helping protect the population and individuals from disease and the subsequent spread of
disease. Vaccinations are responsible for eliminating many of the infectious diseases no
longer common today, and children are especially at risk for infectious diseases because their
immune systems are not as strong as adults, leading to higher mortality rates if infected.
MMR Vaccine
The Measles, Mumps and Rubella Immunization, better known as the MMR
immunization, is a 3-in-1 vaccine that protects against measles, mumps and rubella, all of
which are potentially dangerous childhood illnesses. This immunization first released in 1988
is a shot composed of freeze-dried live attenuated measles, mumps and rubella viruses. The
immunization causes a 90% protection rate against measles and mumps, and 95% protection
rate against rubella. Measles - this can cause ear infections, pneumonia, fits and encephalitis
(inflammation of the brain). Sometimes it can be fatal.
- Mumps - this can cause meningitis, which can result in deafness. It may cause
inflammation of the pancreas, leading to pain, nausea and vomiting. In boys it can
damage the testicles and cause infertility.
- Rubella - this is also known as German measles and is usually a minor illness.
However, it's harmful to pregnant women. If you become infected during the first 10
weeks of pregnancy, it's very likely to cause problems in your unborn baby. These
include heart damage, blindness, deafness and brain damage. It can also lead to
miscarriage. If you become infected with rubella between 10 and 16 weeks, your baby
may still be harmed but the risk is smaller.
The MMR vaccination is a recommended childhood immunization that is typically required
for school entry. The immunization consists of two shots, one of which is to be given at 14-
15 months old, and the other between 4-6 years old. The vaccine is sold by Merck as M-M-R
II, GlaxoSmithKline Biologicals as Priorix, Serum Institute of India as Tresivac, and sanofi
pasteur as Trimovax. Although children usually recover from measles, mumps or rubella,
each illness can be unpleasant and have serious consequences.
Immunization Schedule in Indonesia1
Autism
Definition
Autism is a complex disorder of the central nervous system that has the following 3
defining core features:
- Problems with social interactions
- Impaired verbal and nonverbal communication
- A pattern of repetitive behavior with narrow, restricted interests
A number of other associated symptoms frequently coexist with autism. Most people with
autism have problems using language, forming relationships, and appropriately interpreting
and responding to the external world around them.5
Autism is a behaviorally defined neurodevelopmental disorder that begins in early
childhood. Although the diagnosis of autism may not be made until a child reaches preschool
or school age, the signs and symptoms of autism may be apparent by the time the child is
aged 12-18 months, and the behavioral characteristics of autism are almost always evident by
the time the child is aged 3 years. Language delay in the preschool years (younger than 5
years) is typically the presenting problem for more severely affected children with autism.
Higher functioning children with autism are generally identified with behavioral problems
when they are aged approximately 4-5 years or with social problems later in childhood9
Causes of Autism3
Although autism is the result of a neurologic abnormality, the cause of these problems
with the nervous system is unknown in most cases. Research findings indicate a strong
genetic component. Most likely, environmental, immunologic, and metabolic factors also
influence the development of the disorder.
- G enetic defect that is responsible for autism. Researchers suspect that there are a
number of different genes that, when combined together, increase the risk of getting
autism. In families with one child with autism, the risk of having another child with
autism is 3-8%. The concordance of autism in monozygotic twins is 30%. A number
of studies have found that first-degree relatives of children with autism also have an
increased risk of autism spectrum disorders.
- Neurobiology. Recent development in brain imaging techniques allow for much more
sophisticated investigation of the neurological definicts underlying ASD. Various
abnormalities have been identified(in the fusiform gyrus, amygdala, cerebellum,
cerebral cortex and in overall brain size). Postmortem and neuroimaging studies also
suggest that decreased functional connectivity may play a significant role. However,
the sample size in these studies is typically very small, the diagnostic criteria are often
unclear, intellectual impairment or language level is rarely assessed.
- Environmental factors and exposures may interact with genetic factors to cause an
increased risk of autism in some families.
- Emotional trauma . Some believed that emotional trauma at an early age, especially
bad parenting, was to blame. This theory has been rejected.
- Vaccines Although the mercury preservative used in some vaccines is known to be
neurotoxic, the most recent research on this subject does not suggest a specific link
between vaccines and autism.
Risk Factor of Autism4
Autism affects children of all races and nationalities, but certain factors are known to
increase a child's risk. They include:
- Your child's sex. Studies show that boys are three to four times more likely to develop
autism than girls are.
- Family history. Families who have one child with autism have an increased risk of
having another child with the disorder. It's also not uncommon for the parents or
relatives of an autistic child to have minor problems with social or communication
skills themselves or to engage in certain autistic behaviors.
- Other disorders. Children with certain medical conditions have a higher than normal
risk of having autism. These conditions include fragile X syndrome, an inherited
disorder that causes intellectual impairment; tuberous sclerosis, a condition in which
benign tumors develop in the brain; the neurological disorder.
- Paternal age. Research increasingly suggests that having an older father may increase
a child's risk of autism. One large study showed that children born to men 40 years or
older were almost six times more likely to have autism spectrum disorder than were
children born to men younger than 30 years. Maternal age, on the other hand, seems
to have little effect on autism risk.
Controversy MMR Vacsine that Cause Autism
In February 1998, the Lancet published an article titled “Illeal-Lymphoid-Nodular
Hyperplasia, Non-Specific Colitis and Pervasive Developmental Disorder in Children,”
which suggested that MMR vaccine could contribute to the development of autism. Intense
media coverage of the article followed its publication, and many parents, particularly in the
UK,refuse MMR vaccination of their children. Dr. Andrew Wakefield, a doctor in
experimental gastroenterology at London’s Royal Free Hospital. He published a description
of 12 cases in which toddler patients receiving the MMR vaccine developed gastrointestinal
disorders that led to an increased risk in developing developmental disorders, such as Autism2
Finally, many parents believe the MMR vaccine causes Autism because of the timing
of the proximity in injection/development of the MMR immunization and onset symptoms of
Autism. Controversy MMR Vaccine that cause autism make many people to study and
research The MMR Immunization and Autism: Does correlation mean causation?
MMR Vaccine controversy case study5,6,7,8
1. Study in UK
- The goal of this case-control, community-based study was to test the hypothesis that
measles vaccination was involved in the pathogenesis of ASD.
- Evidence for that hypothesis was defined a priori as signs of a persistent measles
infection or abnormally persistent immune response shown by circulating measles
virus or raised antibody titers in MMR-vaccinated children with ASD and with a
history of regression vs controls.
- Based on these findings, the investigators concluded that there was no association
demonstrated between measles vaccination and ASD.
- Limitations of the study include subjects in the typical development group not
randomly selected from the whole population; parents being informed that the study
was about MMR vaccination may have led to response bias; satisfactory blood
samples not obtained in 100 children, both ASD cases and control group with special
educational needs; and lack of gut mucosal samples for ethical reasons.
- After diagnosis of a developmental problem, children were less likely to receive the
MMR2, which the investigators suggested may reflect parental concern about
vaccination after a diagnosis of a developmental abnormality.
- Both ASD cases and the control group with special educational needs had lower
uptake of MMR2 and, hence, less exposure to the measles virus.
2. Study from The Lancet
- Methods : We did a matched case-control study using the UK General Practice
Research Database. Cases were people born in 1973 or later who had first recorded
diagnosis of pervasive developmental disorder while registered with a contributing
general practice between 1987 and 2001. Controls were matched on age, sex, and
general practice.
- Findings : 1294 cases and 4469 controls were included. 1010 cases (78·1%) had
MMR vaccination recorded before diagnosis, compared with 3671 controls (82·1%)
before the age at which their matched case was diagnosed. After adjustment for age at
joining the database, the odds ratio for association between MMR and pervasive
developmental disorder was 0·86 (95% CI 0·68—1·09). Findings were similar when
restricted to children with a diagnosis of autism, to those vaccinated with MMR
before the third birthday, or to the period before media coverage of the hypothesis
linking MMR with autism.
- Interpretation : Our findings suggest that MMR vaccination is not associated with an
increased risk of pervasive developmental disorders.
3. Study in Denmark
A 2002 retrospective cohort study of all 537,303 children born in Denmark from
January 1991 through December 1998 found no statistically significant difference in
risk of autism among the 440,655 who were vaccinated with MMR. This study
provided strong evidence against the hypothesis that MMR vaccination causes autism.
4. Report from ScienceDaily
Scientists at Columbia University Mailman School of Public Health's Center
for Infection and Immunity and researchers at the Centers for Disease Control and
Prevention, Massachusetts General Hospital, and Trinity College Dublin, evaluated
bowel tissues from 25 children with autism and GI disturbances and 13 children with
GI disturbances alone (controls) by real-time reverse transcription (RT)-PCR for the
presence of measles virus RNA. Samples were analyzed in three laboratories blinded
to diagnosis, including one wherein the original findings suggesting a link between
measles virus and autism had been reported.
"The work reported here eliminates the remaining support for the hypothesis
that autism with GI complaints is related to MMR vaccine exposure. We found no
relationship between the timing of MMR vaccine and the onset of either GI
complaints or autism."
5. 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.
Conclusion
Reviewing both general information found on the scientific literature, it is evident that
there is no proven link between Autism and the receipt of the MMR immunization. The
multiple scientific studies researched in different countries have shown that a global increase
in Autism has occurred even with the decrease and elimination of thimerosal and the MMR
vaccination.
The number of reports on neurologic disorders is very small, other than evidence for
an association between a form of the MMR vaccine containing the Urabe mumps strain and
rare adverse events of aseptic meningitis, a transient mild form of viral meningitis. Evidence
suggests that almost everyone who has had a successful immunisation is protected against
these diseases for life.
References :
1. Ikatan Dokter Anak Indonesia. Jadwal Imunisasi. Available at
http://dranak.blogspot.com/2007/03/jadwal-imunisasi.html. Accessed January
17,2010.
2. Immunization Action Coalition. MMR Vaccine Does Not Cause Autism. Available at
http://www.immunize.org/catg.d/p4026.pdf. Accessed January 17, 2010.
3. Cynthia R Ellis. Autism. Available at
http://www.emedicinehealth.com/autism/page18_em.htm. Accessed January 17, 2010.
4. Mayo Clinic. Autism Risk Factors. Available at
http://www.mayoclinic.com/health/autism/DS00348/DSECTION=risk-factors.
Accessed January 17, 2010.
5. Marlene Busko. MMR Vaccine Not Linked to Autism in Virologic Case Control
Study. Available at http://www.medscape.com/viewarticle/569974. Accessed January
23, 2010.
6. The Lancet. MMR Vaccination and Pervasive Developmental Disorder: a Case-
Control Study. Available at
http://www.thelancet.com/journals/lancet/article/PIIS0140-6736(04)17020-7/abstract.
Accessed January 23, 2010.
7. MMR Vaccine Controversy. Available at http://www.answers.com/topic/mmr-
vaccine-controversy. Accessed January 30, 2010.
8. ScienceDaily. No Connection Between Mumps, Measles, Rubella (MMR) Vaccine
and Autism, Study Suggest. Available at
http://www.sciencedaily.com/releases/2008/09/080904145218.htm. Accessed January
30,2010.
9. F. Weems, Carl. Journal of Autism and Developmental Disorders. 2010