Someone a while ago posted a statistic about the fraction of flu vaccines containing thimerosol still. This came up in another thread on these boards a few weeks ago. I tried to track down the 90% number which many anti-vaccination sites quote, but can only find it on anti-vaccination sites (as I explain below).
This is the full thread:
I'll copy one of my posts from there:
It could be seen as misleading to cite these new autism numbers as "proving" and increase in autism is continuing despite the removal of thimerosol in vaccines. The dates do seem a bit tight, and unless I'm missing something I do think reporting the results in this way is doing a disservice to our intelligence. However, my facts (with references) do differ somewhat from the ones previously posted:
Since 2001 no new vaccine licensed by FDA for use in children has contained thimerosol, and all vaccines routinely recommended by CDC for children younger than 6 years of age have been thimerosal–free, or contain only trace amounts of thimerosal, except for multi–dose formulations of influenza vaccine.(http://www.cdc.gov/flu/protect/vaccine/thimerosal.htm). The original suggestions to start removing/reducing thimerosol seems to have come in 1999 (http://www.fda.gov/BiologicsBloodVaccines/SafetyAvailability/VaccineSafety/UCM096228#act)
In 2011-2012, out of 13 flu vaccination formulations, 4 contain thimerosol (which is 30% of them; and is only those sold in multi-dose vials where risk of infection is high and therefore the antibacterial properties of thimerosol are needed). http://www.cdc.gov/flu/protect/vaccine/vaccines.htm
I have yet to find information on the usage rates of the different vaccination formulations, but I cannot find any suggestion that 90% contain thimerosol. What I did find was a press release from "Put Children First" from 2006 which claimed the 90% figure, but gave no data, and NVIC also claim 80-90% on their "Mercury in Vaccines" page, but again no data.
Recent media news about autism rates were based on data collected on 8 year olds in 2008 - and therefore they were indeed born in 2000, receiving most childhood vaccines presumably in 2000 or 2001 just around the time thimerosal was being removed from all childhood vaccines. http://www.cdc.gov/ncbddd/autism/data.html
Interestingly the rates in boys and girls were drastically different (as they have been in all previous reports). Autism rates are 5 times higher in boys than girls, while vaccination rates I assume are similar (for that I have found no data I admit!).
If the autism study dates follow the pattern in the table here http://www.cdc.gov/ncbddd/autism/data.html the next report will be published in 2014 based on data collected in 2010, before any change to the ASD diagnosis information, and based on children born in 2002, after thimerosol was removed from all childhood vaccines. It will be interesting to see the outcome of that. A study based on new guidelines if they are implemented this year would not be published until 2016 (if it continues to be 4 years between data collection and study publication.
Independent studies show no link between thimerosol containing vaccines and autism, for example:
" In our study of MCO (managed care organization) members, prenatal and early-life exposure to ethylmercury from thimerosal-containing vaccines and immunoglobulin preparations was not related to increased risk of ASDs (autism spectrum disorders)."
I also should reference the wikipedia page on Thimerosol: http://en.wikipedia.org/wiki/Thiomersal. If you think they have their facts wrong you can try to edit it following their rules for properly referencing the source of your facts.