Doctors’ Notes


Vaccines & Preservatives

As a parent, you have questions and concerns regarding the health and care of your child — as you should! As providers, we want to be sure your children receive the best possible care.

One of the concerns many parents have is about the preservatives used in vaccines — which are some of the best possible care we give. This note, which includes lots of great information from the Centers for Disease Control and Prevention (CDC) and the Food and Drug Administration (FDA), will address those concerns.

Why are Preservatives Used?

vaccinationsPreservatives are used in vaccines, quite simply, to keep your child safe. They prevent contamination of the vaccines with bacteria or fungi. Prior to preservatives in vaccines, there was a tragic incident in 1928 in which many children were infected by a contamination of staph in a vaccine to protect against diphtheria. That contamination led to multiple fatalities.

Preservatives were added and implemented to prevent occurrences like this. Multi-dose vials (like flu vaccines) may contain preservatives,  because of the recurrent introduction of needles into the vial.

What About Thimerosal?

Today, thimerosal — the most commonly known and frequently talked about preservative — is used in a select few vaccines, and only in very small amounts. (The vast majority of vaccines never contained it.) Many, many studies have been done that indicate thimerosal is safe.

How Do I Know It’s Safe?

To cite the CDC: “Thimerosal use in medical products has a record of being very safe. Data from many studies show no evidence of harm caused by the low dose of thimerosal in vaccines.”  The FDA Modernization Act of 1997 found that using thimerosal as a preservative in vaccines showed no evidence of harm.

The Council on Foreign Relations (CFR) notes that preservatives in vaccines are required to be “sufficiently non-toxic so that the amount present in the recommended dose of the product will not be toxic to the recipient.”

In short, as with any ingredient: it’s all about the dose. Thimerosal, upon entering the body, quickly breaks down into two byproducts that are quickly eliminated from the body and do not build up to a level of concern.

What About a Link to Autism?

Despite many claims and Facebook posts to the contrary, no study has ever proven, or even suggested, a link between thimerosal and autism. In fact, once thimerosal was removed from the majority of vaccines as a preservative, the rate of autism continued to increase, which is exactly the opposite of what should have happened if if thimerosal were a cause of autism.

What Vaccines at Kids Plus Contain Preservatives?

All of the vaccines we use at Kids Plus are free of thimerosal except for the multi-dose Fluzone injectable flu vaccine, which contains a concentration of just 0.01%. All other vaccines we give do not contain preservatives.

For more information about all of the vaccines we provide, see the Vaccine Information Statements page of our web site.

The web site has a wonderful resource page, with a table that addresses all of the vaccines, and whether they contain (or ever contained) thimerosal. You can see that here.

As always, if you have any questions or concerns, just let us know, and we’ll be happy to help.

Alyssa Mathews, a certified Physician Assistant, joined Kids Plus in June 2012.