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Originally Posted by Clodfobble

Incorrect. There is enough evidence that thimerosal is dangerous that the CDC readily admits that babies under 6 months should not get the flu vaccine, or should get a non-thimerosal dose.

Wikipedia: (bold mine of course)

The FDA noted that while the vaccination schedule at that time might have exceeded EPA standards for mercury exposure during the first 6 months of life, it did not exceed those of the FDA, Agency for Toxic Substances and Disease Registry (ATSDR), or WHO. The FDA also noted difficulty interpreting toxicity of the ethylmercury in thiomersal because guidelines for mercury toxicity were based primarily on studies of methylmercury, a different mercury compound with different toxicologic properties. Despite the lack of convincing evidence of toxicity of thiomersal when used as a vaccine preservative, the USPHS and AAP determined that thiomersal should be removed from vaccines as a purely precautionary measure. This action was based on the precautionary principle, which assumes that there is no harm in exercising caution even if it later turns out to be unnecessary. The CDC and AAP reasoned that despite the lack of evidence of significant harm in the use of thiomersal in vaccines, the removal of this preservative would increase the public confidence in the safety of vaccines.

http://en.wikipedia.org/wiki/Thimerosal

Concerns based on extrapolations from methylmercury caused thiomersal to be removed from U.S. childhood vaccines, starting in 1999. Since then, it has been found that ethylmercury is cleared from the body and the brain significantly faster than methylmercury, so the late-1990s risk assessments turned out to be overly conservative. A 2008 study found that the half-life of blood mercury after vaccination averages 3.7 days for newborns and infants, much shorter than the 44 days for methylmercury.

Further detail:

To illustrate, researchers cite that infants in the 6-month-old group – who, in their lifetimes, had encountered more total ethyl mercury that any other group studied – still had the same pre-vaccination blood-mercury levels before their checkups as most 2-month-olds had before theirs. This suggests that, before each round of shots, the mercury has plenty of time to be cleared.

tl;dr: The ban was precautionary, not based on evidence of harm. Some of the considerations of harm were based on studies of the toxicology of methylmercury, even though the metabolite of Thimerosol is actually ethylmercury. Since the ban, ethylmercury has been found to be much less accumulative than methylmercury.

I thought you preferred evidence? There were studies linked earlier in this thread that showed that a decline in the number of flu vaccinations did not lead to an increase in the number of flu infections or deaths. Your entire argument is predicated on the idea that the flu vaccine actually does anything to stop the flu, and the evidence shows it doesn't do that.

http://www.cdc.gov/FLU/PROFESSIONALS...tivenessqa.htm



It's confusing, because the effectiveness varies from year to year as scientists to get the exact strain for that year. So a study of effectiveness should take into account overall effectiveness, not the effectiveness of one year. Overall:

Overall, in years when the vaccine and circulating viruses are well-matched, influenza vaccines can be expected to reduce laboratory-confirmed influenza by approximately 70% to 90% in healthy adults <65 years of age. Several studies have also found reductions in febrile illness, influenza-related work absenteeism, antibiotic use, and doctor visits.

In years when the vaccine strains are not well matched to circulating strains, vaccine effectiveness can be variably reduced. For example, in a study among persons 50-64 years during the 2003-04 season, when the vaccine strains were not optimally matched, inactivated influenza vaccine effectiveness against laboratory-confirmed influenza was 60% among persons without high-risk conditions, and 48% among those with high risk conditions, but it was 90% against laboratory-confirmed influenza hospitalization (Herrera, et al Vaccine 2006). A study in children during the same year found vaccine effectiveness of about 50% against medically diagnosed influenza and pneumonia without laboratory confirmation (Ritzwoller, Pediatrics 2005). However, in some years when vaccine and circulating strains were not well-matched, no vaccine effectiveness can be demonstrated in some studies, even in healthy adults (Bridges, JAMA 2000). It is not possible in advance of the influenza season to predict how well the vaccine and circulating strains will be matched, and how that match may affect the degree of vaccine effectiveness.