Someone did perform safety studies the U.S. Centers for Disease Control and Prevention (CDC) and the U.S. Food and Drug Administration (FDA) should have mandated be performed and vetted BEFORE numerous vaccines were released into the public sector for mass vaccinations.
Lead investigator Laura Hewitson, PhD, probably dropped a bombshell when she and her colleagues completed a macaque monkey (primates) study of the very same vaccines given to children during 1994-1999, i.e., the Measles-Mumps-Rubella (MMR) vaccine and several Thimerosal mercury-containing vaccines injected into children during that time frame when the autism spectrum disorder skyrocketed.
The results of that pilot study were published as a Research Paper in Acta Neurobiological Experimentals in 2010 and titled “Influence of pediatric vaccines on amydgala growth and opioid ligand binding in rhesus macaque infants: A pilot study.”  Even though there was alleged controversy revolving around Hewitson’s monkey studies, e.g., charges of conflicts of interest since she filed a claim with the vaccine court on behalf of her child,  the information generated needs to be revisited and duplicate studies need to be undertaken.
Why haven’t they? Is there too much influence from vaccine makers not to do them? Parents need to make demands on the U.S. Congress to require such safety studies on monkeys be duplicated immediately, plus suspend all mandates on vaccinations until the study results are in. Did Dr Hewitson become another professional persona non-grata because she may have been on the right track?
Congress needs to consider seriously the Hewitson, et al. report that stated:
“Vaccine-exposed and saline-injected control infants [monkeys] underwent MRI and PET imaging at approximately 4 and 6 months of age, representing two specific timeframes within the vaccination schedule. …
“These results suggest that maturational changes in amygdala volume and the binding capacity of [11C]DPN in the amygdala was significantly altered in infant macaques receiving the vaccine schedule.” 
That alone should be the explicit reason for duplicating the monkey study with independent non-pharmaceutical industry conflict of interest scientists.
In this author’s opinion, no one has bigger conflicts of interest in study outcomes than the pharmaceutical makers who routinely perform them. Those are the very studies that should be subject to the same criticism as Dr Hewitson’s. Why aren’t they? Good question?
For those keeping track data, ASD went from 1 in 5,000 in the 1990s to the recently acknowledged [March 2012] figures of 1 in 88 along with 1 in 6 children in the USA having developmental disabilities. These stats were generated for data in the years 2006 to 2008.  There’s a 4 to 6 year lag time. Could ASD be 1 in 50 by now at the rate it is escalating?, especially since there’s a heavier push on mandates for vaccinations.
According to the Hewitson, et al. research study, biological changes and altered behaviors did occur in vaccinated monkeys, which resembled and were similar to those observed in ASD diagnosed children. However, there were no such symptoms showing or present in unvaccinated monkeys.
Don’t you just gotta love those little monkeys! Guess what else the ASD monkeys came up with, and Dr Wakefield is gonna like this one: Gastrointestinal problems manifested in vaccinated macaques such as “many significant differences in the GI tissue gene expression profiles between vaccinated and unvaccinated animals.” 
It’s been a deeply debated topic within medicine that vaccinated children who contract ASD also have GI tract issues. Personally, I gotta wonder how the British Medical Journal is going to deal with encrusted dried egg on its face when duplicate studies confirm the Hewitson monkey results. Perhaps the infamous BMJ retraction of the Wakefield article and Doctor’s professional evisceration, commonly referred to as the “Wakefield Syndrome,” euphemistically speaking is medicine protecting its vested interests.
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