VIDEO
Dr. Andrew Wakefield ~ BREAKING NEWS ~ MMR Vaccine / Autism Link Confirmed
What have studies found regarding the MMR vaccine and autism?
An epidemiologic study is a study of how often a disease occurs in different groups of people and why the disease occurs.
Epidemiologic studies do not focus on individuals, but rather look at the frequencies and types of diseases in whole populations of people. These studies are used when trying to learn the reason for increases or deceases in the rates of diseases. In the United States, the CDC is the main source of epidemiologic information. It has conducted many epidemiologic studies of autism and these studies have shown no relationship between MMR vaccination in children and an increased risk of autism. The following is a brief summary of some of the major studies on this topic:
● In 1997, the National Childhood Encephalopathy Study was examined to see if there was any link between measles vaccine and neurological events. The researchers found no indication that measles vaccine contributed to the development of long-term neurological damage, including educational and behavioral deficits (Miller et al., 1997).
● A study by Gillberg and Heijbel (1998) examined the prevalence of autism in children born in Sweden from 1975–1984. There was no difference in the prevalence of autism among children born before the introduction of the MMR vaccine in Sweden and those born after the vaccine was introduced.
● In 1999, the British Committee on Safety of Medicines convened a “Working Party on MMR Vaccine” to conduct a systematic review of reports of autism, gastrointestinal disease, and similar disorders after receipt of MMR or measles, mumps, rubella vaccine.
It was concluded that the available information did not support the posited associations between MMR and autism and other disorders.
● Taylor and colleagues (1999) studied 498 children with autism in the United Kingdom and found the age at which they were diagnosed was the same regardless of whether they received the MMR vaccine before or after 18 months of age or whether they were never vaccinated. Importantly, the first signs or diagnoses of autism were not more likely to occur within time periods following MMR vaccination than during other time periods. Also, there was no sudden increase in cases of autism after the introduction of MMR vaccine in the United Kingdom. Such a jump would have been expected if MMR vaccine was causing a substantial increase in autism.
● Kaye and colleagues (2001) assessed the relationship between the risk of autism among children in the United Kingdom and the MMR vaccine. Among a subgroup of boys aged 2–5 years, the risk of autism increased almost fourfold from 1988 to 1993, while MMR vaccination coverage remained constant at approximately 95 percent over these same years.
● Researchers in the United States found that among children born between 1980 and 1994 and enrolled in California kindergartens, there was a 373 percent relative increase in autism cases, though the relative increase in MMR vaccine coverage by the age of 24 months was only 14 percent (Dales et al., 2001).
● Researchers from the United Kingdom conducted a study to test the theory that a new form or new variant of inflammatory bowel disease (IBD) existed.
This new variant of IBD had been described as a combination of autism and gastrointestinal symptoms. The neurological and gastrointestinal symptoms seemed to occur shortly after the child received his MMR immunization. Further, the neurological component followed the developmental regression type of onset. To study this theory, the researchers gathered medical information on 96 children (95 immunized with MMR) who were born between 1992 and 1995 and who were diagnosed with pervasive developmental disorder. The data from this group of children were compared with data from two other groups of autistic patients. One group of 98 children were born before MMR was ever used, and one group of 68 children were likely to have received MMR vaccine. No evidence was found to support a new syndrome of MMR-induced IBD/autism. For instance, the researchers found that there were no differences between vaccinated and unvaccinated groups with regard to the time when their parents first became concerned about their child’s development. Similarly, the rate of developmental regression reported in the vaccinated and unvaccinated groups was not different; therefore, there was no suggestion that developmental regression had increased in frequency since MMR was introduced.
Of the 96 children in the first group, no IBD was reported. Furthermore, there was no association found between developmental regression and gastrointestinal symptoms.
● Another group of researchers in the United Kingdom (Taylor et al., 2002) also examined whether the MMR vaccination can be associated with bowel problems and developmental regression in children with autism. The study included 278 cases of children with autism and 195 with atypical autism (cases with many of the features of childhood autism but not quite meeting the required criteria for that diagnosis or with atypical features such as onset of symptoms after the age of 3 years). The cases included in this study were born between 1979 and 1998. The proportion of children with developmental regression or bowel symptoms did not change significantly from 1979 to 1988, a period that included the introduction of MMR vaccination in the United Kingdom (1988).
No significant difference was found in the rates of bowel problems or developmental regression in children who received the MMR vaccine. There was no difference between the 3 groups in the time to the parent’s recognition of developmental delays. The findings of this study do not support the existence of a new type of autism that is caused by the MMR vaccination. Additionally, it suggests that there is no link between autism and MMR vaccinations.
● Madsen and colleagues (2002) conducted a study of all children born in Denmark from January 1991 through December 1998. There were a total of 537,303 children in the study; 440,655 of the children were vaccinated with MMR and 96,648 were not. The researchers did not find a higher risk of autism in the vaccinated than in the unvaccinated groups of children. Furthermore, there was no association between the age at time of vaccination, the amount of time that had passed since vaccination, or the date of vaccination and the development of any autistic disorder. Although there were many more vaccinated than unvaccinated children in the study group, the sample was large enough to contain more statistical power than other MMR and autism studies. Therefore, this study provides strong evidence against the hypothesis that MMR vaccination causes autism.
● DeStefano and associates (2004) conducted a study to see if there was a difference in the age at which children with autism and those without autism received their first MMR vaccination. The study’s findings showed that children with autism received their first MMR vaccination at similar ages as children without autism. More information about this study can be found on the CDC’s research on vaccines and autism Web page: http://www.cdc.gov/nip/vacsafe/concerns/autism/autism-mmr.htm
Terms:
Prevalence – The proportion of people with a particular condition or disease within a given population at a given time.
Rubella – German measles.
Developmental regression – A form of autism in which infants, after apparently normal development, start to lose language and other skills. This condition is fairly rare and has not been well described nor does it have scientifically established standards for diagnosis.
