In addition to genetics and metabolism, mercury exposure and vaccines have been implicated as a possible cause of autism. My previous article covered studies about genetic and metabolism causes and this article continues with research regarding vaccines.

Old style DPT vaccines used to contain thimerosal, a 49 percent mercury compound. Some DTaP vaccines still contain small amounts of mercury, according to the CDC Pink Book. Other vaccines, such as Hepatitis B and flu shots contain the full amount of thimerosal.

Some researchers believe that the increasing number of vaccines given at one time to a developing infant are a cause of autism, particularly as the blood/brain barrier is not yet complete.

A study in the Annals of Epidemiology found that newborn boys who had received Hepatitis B vaccine were three times more likely to be diagnosed with an ASD compared with boys who hadn’t had the jab.

"Findings suggest that U.S. male neonates vaccinated with hepatitis B vaccine had a 3-fold greater risk of ASD; risk was greatest for non-white boys." (2)

Autism symptoms and mercury poisoning symptoms are virtually identical. The Journal of Immunotoxicology wrote:

"Autistic brains show neurotransmitter irregularities that are virtually identical to those arising from mercury exposure. Due to the extensive parallels between autism and mercury poisoning, the likelihood of a causal relationship is great."

These neurotransmitter irregularities may be the reason why some autistic children have sensory processing disorders. (1)

MMR Vaccine

MMR vaccine is considered a possible cause of autism. In 1998 a gastroenterologist called Andrew Wakefield and his team of clinicians identified 12 children, eight of whom suffered regressive autism and gastrointestinal disease. After publishing this case paper, concluding that it did NOT prove an association with MMR, Dr. Wakefield studied a further 161 children, 91 of whom had bowel disease and a further 70 who did not.

He found measles virus in the guts of 75 of the children with bowel disease and only in five of the healthy children. He called this condition "measles enterocolitis". It was already widely known that wild measles virus can cause colitis so theoretically a live virus vaccine like MMR could do the same. (3 and 4)

A further three children with regressive autism were found to have measles vaccine virus in their cerebrospinal fluid after a spinal tap had been performed.

"In light of encephalopathy presenting as autistic regression (autistic encephalopathy, AE) closely following measles-mumps rubella (MMR) vaccination, three children underwent cerebrospinal fluid (CSF) assessments including studies for measles virus (MV). All three children had concomitant onset of gastrointestinal (GI) symptoms and had already had MV genomic RNA detected ... None of the cases or controls had a history of measles exposure other than MMR vaccination."

They thought this raised the possibility of virally-driven brain damage resulting in some cases of regressive autism. (5)

Early life exposure to mercury and other metals, followed by exposure to live viruses could potentially tip the child into autoimmunity.

Fetal Tissue

Some vaccine viruses are cultured on fetal tissue cells obtained from aborted fetuses. Although it isn’t an added ingredient, trace amounts of fetal DNA will remain in the vaccine. Vaccines that contain fetal DNA include MMR, varicella, some Hepatitis B vaccines and Hepatitis A.

Children can produce antibodies to all components of vaccines and not merely the viruses or bacteria, so injecting fetal DNA can cause the child to develop antibodies to human tissue, another possible factor in autism.

Doctors in Portugal blood tested 171 autistic patients, 191 parents and 54 healthy people and found that the autistic patients had high levels of non-inherited antibodies to their own brain tissue. (6)

Spikes in the incidence of autism were seen in the UK in 1988 when the MMR was introduced and in the United States in 1995 when varicella vaccine was introduced, pointing to a possible link with fetal tissue in vaccines. (1)

It is important that research into the childhood vaccination schedule be continued, particularly while rates of autism show no sign of slowing down.

Sources:

1. Theoretical aspects of autism: Causes—A review, Journal of Immunotoxicology. Web. 8 September 2011.
http://www.cogforlife.org/ratajczakstudy.pdf

2. Hepatitis B Vaccination of Male Neonates and Autism, Annals of Epidemiology. Web. 8 September 2011.
http://www.annalsofepidemiology.org/issues

3. Measles study raises bowel disease link, BBC News (2002). Web. 8 September 2011.
http://news.bbc.co.uk/1/hi/health/1803005.stm

4. Enterocolitis, autism and measles virus, Molecular Psychiatry. Web. 8 September 2011.
http://www.ncbi.nlm.nih.gov/pubmed/12142948

5. Detection of Measles Virus Genomic RNA in Cerebrospinal Fluid of Children with Regressive Autism: a Report of Three Cases, Journal of American Physicians and Surgeons. Web. 8 September 2011. http://www.jpands.org/vol9no2/bradstreet.pdf

6. Autoantibody repertoires to brain tissue in autism nuclear families, Journal of Neuroimmunology. Web. 8 September 2011.
http://www.sciencedirect.com/science/article/pii/S0165572804001213

Joanna is a freelance health writer for The Mother magazine and Suite 101 with a column on infertility, http://infertility.suite101.com/. She is author of the book, 'Breast Milk: A Natural Immunisation,' and co-author of an educational resource on disabled parenting.

She is a mother of five who practised drug-free home birth, delayed cord clamping, full term breast feeding, co-sleeping, home schooling and flexi schooling and is an advocate of raising children on organic food.

Reviewed September 8, 2011
by Michele Blacksberg R.N.
Edited by Jody Smith