Thimerosal-Containing Flu Vaccine Given During Pregnancy Causes Tics, CDC Scientist Says

Senior CDC Scientist William Thompson was recorded stating that flu vaccines containing Thimerosal can cause tics in children if the vaccine is administered to their mothers during pregnancy. Though Thompson said in a statement that he was not aware that he was being recorded, he did admit that it was his voice in the recordings. He is still employed with the CDC and has acquired a lawyer that specialized in protecting whistleblowers.

“I can say confidently I do think, ah, Thimerosal causes tics,” the CDC scientist said in a conversation with Dr. Hooker that was recorded. “So, I don’t know why they still give it to pregnant women.”

The CDC states, “Flu shots have not been shown to cause harm to pregnant women or their babies. It is very important for pregnant women to get the flu shot.”

Thompson’s recorded statements about Thimerosal causing tics in children when given to pregnant women were his vocalized opinions. The CDC evidently feels at this time that he was entitled to his opinion, because he is still employed with the CDC. The statement leaves people wanting to know more about Thimerosal, pregnancy, and tics, though.

“TICs are movement disorders. And phonic TICs are disorders of the – movement of the tongue actually, so they are utterances that are abnormal,” Anne Schuchat, Director of the National Center for Immunization and Respiratory Diseases, said at a press conference in 2007, according to the CDC’s website. Thimerosal is a preservative used in a small number of vaccines, including multi-dose vials of the seasonal flu vaccine. It consists of almost half ethyl mercury. The CDC recommends that the flu vaccine be given every single year. So, while Thimerosal has been phased out of most vaccines, millions of people get one of the few remaining Thimerosal-containing vaccinations every single year.

According to the FDA, seasonal influenza virus vaccines are routinely recommended for all pregnant women. According to the FDA, Thimerosal in the flu vaccine is perfectly safe for use during pregnancy. As evidence of safety on the FDA’s “Thimerosal in Vaccines” page, the FDA offers only a few studies.

In one of the most applauded studies, researchers gave squirrels sodium ethylmercurithiosalicylate (Thimerosal) in their nostrils every day for six months to determine how much of it gets stored in tissue and where when given through the nasal passages. The researchers found no toxicity in any animals when it was put up their nose, but found that it did build up significantly in the kidney, moderately in liver, and slightly in brain and muscle. The researchers didn’t test what happens if the ethyl mercury based compound was injected in that study.

The FDA’s “Thimerosal in Vaccines” page said that it is also worth noting a more recent study from the University of Rochester and National Naval Medical Center. According to the FDA, those researchers checked blood levels of mercury after infant vaccination in their study and infant blood mercury levels never exceeded safety guidelines. The study also asserted that the “estimated blood half-life of ethyl mercury was 7 days.”

“The heavy metals mercury, lead, and cadmium are toxicants, which are well-known to cross the placenta and to accumulate in fetal tissues,” researchers at Institute of Medical Genetics at the Medical University of Vienna wrote. “Both metal-specific placental transfer and impairment of placental function can explain the relationships between prenatal metal exposures and adverse effects on intrauterine growth and (neuro)development.”

Mercury, even ethyl mercury, can cross the placenta.

According to a slideshow on the Institute of Medicine’s webpage, the other study the FDA used as evidence on the “Thimerosal in Vaccines” page might not be that supportive of Thimerosal safety in pregnancy either, because in the 1985 study cited by the FDA, higher levels of inorganic mercury were seen in brains of mice that had been treated by the “less toxic” ethyl mercury than the “more toxic” and more heavily studied methyl mercury. So, that study that the FDA linked to demonstrated that the kind of mercury used in vaccines leaves higher levels of inorganic mercury in the brain.

The FDA has a chart online that informs the public of the Thimerosal content in vaccines. Measurable quantities of Thimerosal is found in FluZone (multi-dose), Fluvirin (multi-dose), and Afluria (multi-dose). The single-dose versions, on the other hand, are all either completely mercury free or contain only trace amounts. The nasal flu vaccine FluMist is a live vaccine that contains no mercury at all; however, according to Medicine Net, this live flu vaccine should never be given to pregnant women.

Pregnant women who want to be vaccinated against the flu could consider making sure their flu shots come from the single-dose vials instead of the multi-dose vials.

Pregnant women should be aware that according to each of the flu vaccines’ manufacturers, none of them have been established as safe for pregnant women. Each of the following statements were taken directly from the manufacturers’ package inserts or prescribing information.

Safety and effectiveness of Fluzone has not been established in pregnant women.

Safety and effectiveness of FLUVIRIN® have not been established in pregnant women, nursing mothers or children less than 4 years of age.

Safety and effectiveness of AFLURIA have not been established in pregnant women or nursing mothers.

Safety and effectiveness of FluMist have not been established in pregnant women, nursing mothers, geriatric adults, or children less than 2 years of age.

Still, the FDA believes that enough pregnant women have used flu vaccines with Thimerosal for them to be considered safe at this time, even if the manufacturer can’t make that claim.

It shouldn’t be terribly surprising that Thompson believes that flu vaccines containing Thimerosal administered to pregnant women might cause tics in their offspring. Thompson himself was one of the co-authors of the research paper “Thimerosal exposure in early life and neuropsychological outcomes 7-10 years later” That article was published in the Journal of Pediatric Psychology and it showed a small, but statistically significant association between early Thimerosal exposure and the presence of tics in boys. The full article can be found online for free, and press conference transcripts about Thimerosal and tics can be found on the CDC’s website.

“Do you think that a pregnant mother would want to take a vaccine that they knew caused tics,” the CDC senior scientist William Thompson asked. Having stated his belief that Thimerosal in vaccines can cause tics when administered during pregnancy, Thompson answered his own question, “Absolutely not! I would never give my wife a vaccine that I thought caused tics.”