Folllow up on Vaccine Post: Is Thimerosal really gone?

Today I was reading this post on Mom's Speak Up, about one mom's struggle with her daughter's serious reactions to vaccines, and an awful doctor who threatened, belittled and bullied her into a chickenpox vaccination on her child. You can read the post here. This mama ultimately decided to vaccinate her child, but with some thoughtful adjustments to the regular schedule (and other ideas to decrease her child's chance of a reaction).

One thing she did say in the article that made me pause was this: "Thimerosal (mercury) is not 100% removed from vaccines. Even doctors in the American Academy of Pediatrics admit it is usually 90% removed, not 100%." And she cited this article from Reuters, which explains that Thimerosal has been phased out of most vaccines, but is still in flu vaccines (along with many other potentially toxic substances such as aluminum). That certainly got my attention since I have been assured that there is no thimerosal in the vaccines given in my pediatrician's office, and by a doctor on the news clip I cited in my recent post on vaccines.

Here is a quote from the American Academy of Pediatrics about the safety and use of thimerosal:

"Some parents have expressed concerns about a potential link between health problems, particularly autism, and vaccines containing thimerosal. Thimerosal is a preservative that contains a form of mercury (organomercurial). Beginning in the 1930s, thimerosal was used in very small amounts as a preservative in vaccines. Thimerosal is effective in preventing bacterial and fungal contamination, particularly in opened multi-dose vaccine containers. In 1999, the Public Health Service agencies and the AAP recommended that thimerosal be taken out of vaccines as a precautionary measure. By the end of 2001, all routine pediatric vaccines contained no thimerosal or only trace amounts (some influenza and Td vaccines). There is no convincing evidence of harm caused by the small amounts of thimerosal in vaccines, except for minor effects like swelling and redness at the injection site due to sensitivity to thimerosal."

This is in stark contrast to the Reuters article about the same topic. The main difference I see is the language of there being "trace" amounts of thimerosal in vaccines, so let's explore this further. The Centers for Disease Control and the American Academy of Pediatrics say that all vaccines (accept the flu vaccine) have either no thimerosal or only trace amounts. The flu vaccine, for whatever reasons, has a higher rate of thimersol present (although still considered safe, according to the CDC and the AAP).

Here is a more through explanation from the CDC:

"Today, all routinely recommended licensed pediatric vaccines that are currently being manufactured for the U.S. market, with the exception of influenza vaccine, contain no thimerosal or only trace amounts. Thimerosal preservative-free influenza vaccines are available, but in limited quantities. The total amount of inactivated influenza vaccine available without thimerosal as a preservative will continue to increase as manufacturing capabilities are expanded."

Read the rest of the CDC article here, which goes on to cite the studies indicating the use of thimerosal in vaccines presents no harm. The short of it is that regular flu vaccines can still contain thimerosal, and you can request one without it for your child. This seems like the best choice to me, but I do worry about the parents who do not know about this choice or do not have this (albeit confusing) information.

There have been recent studies disproving the link between thimerosal and autism. Read a recent article on this from Science Daily here. Here is a roundup of the prevailing medical opinion about the relationship between thimerosal and autism, from ABC news.

The Centers for Disease Control says "There is no convincing scientific evidence of harm caused by the low doses of thimerosal in vaccines, except for minor reactions like redness and swelling at the injection site."

The American Academy of Pediatrics says"No scientific data link thimerosal used as a preservative in vaccines with any pediatric neurologic disorder, including autism."

The Food and Drug Administration conducted a review in 1999 -- the year thimerosal was ordered to be removed from most vaccines -- and said that it "found no evidence of harm from the use of thimerosal as a vaccine preservative, other than local hypersensitivity reactions."

The Institute of Medicine’s Immunization Safety Review Committee concluded "that the body of epidemiological evidence favors rejection of a causal relationship between thimerosal-containing vaccines and autism."

And a study of California Department of Developmental Services data published last month indicated that there was "an increase in autism in California despite the removal of thimerosal from most vaccines."

So is thimerosal gone from vaccines? The best answer I can give from this research is: mostly (which is not very satisfying, I know). I would encourage you to discuss this more with your child's pediatrician if you are concerned or want more information.

It is truly my goal to provide readers with balanced, thoughtful information, with links to the sources for parents to read and consider. I am not a doctor, only a concerned parent and writer. I want what is best for all of our kids. Please take this post and others as simply more information for you as you and your child's doctor make important decisions about your child's health.


Sources: American Academy of Pediatrics, Centers for Disease Control, ABC news, Science Daily