Over the past several years, there has been a great deal of information and misinformation in the press regarding alleged associations between vaccines, mercury content and autism. We would like to clarify the situation in order to dispel some common myths and fears about these issues.

The most widely publicized piece of misinformation came from the United Kingdom regarding a possible association between the MMR (measles, mumps and rubella) vaccine and autism. Autism is a developmental disorder that is most commonly identified between 18 and 30 months of age; the MMR vaccine is commonly given between 15-18 months of age. However, this does not by default mean that the MMR vaccine is the cause of autism. In fact, there is no scientifically valid evidence that the MMR vaccine causes autism. Both the American Academy of Pediatrics (AAP) and the Centers for Disease Control and Prevention (CDC) have found no association between the MMR vaccine and autism, as have numerous, reproduced studies from many other countries. It should also be noted that one of the lead authors of the original article purporting such a link has been found to have accepted financial reimbursement from an attorney representing several of the children included in his study.

Autism is a genetic, developmental disease that many experts believe begins before birth. Research has shown that some children with autism have brain abnormalities that can be identified prenatally. We have seen a rise in the number of children with autism because parents and doctors are becoming better at diagnosing the disorder. Forty years ago, only those children with severe autism were recognized, diagnosed and received any services for the disorder. Today, the criteria that we use to diagnose autism have become more inclusive and more children are appropriately receiving therapies targeted toward their symptoms.

The second piece of widely publicized MISinformation is the supposed link between thimerosal and autism. Thimerosal is a mercury based preservative previously used in several vaccines including Hepatitis B and Influenza. This preservative prolonged the shelf life of many vaccines, enabling a larger number of children to receive protection against many vaccine preventable diseases. It is well known that mercury ingestion in large quantities can result in kidney and brain damage. This led to the concern that thimerosal can cause autism. However, the amount of mercury in vaccines is very small; in fact, environmental exposures to mercury, such as eating certain fish (i.e. tilefish and swordfish) expose us to larger quantities of mercury than vaccines do. However, in response to public outcry, thimerosal has been removed from all routine vaccines. The influenza vaccine is the only common vaccine that still uses thimerosal as a preservative, and in trace amounts well below the limits set by the CDC and World Health Organization (WHO) (this is the case in the multidose vials of the flu vaccine only; the single dose vials are preservative free). Depending upon vaccine availability, we usually have flu vaccine without thimerosal.

If you would like more information about either of the above topics, please read this from the American Academy of Pediatrics, or this from the website of Centers for Disease Control and Prevention. While we are proponents of vaccines and the protection they afford children, the physicians at Kids First Pediatrics are vigilant about ensuring that all vaccines administered in our office are safe for your child.