Below is a press release from the Johnson Center for Child Health and Development (formerly Thoughtful House). The press release discusses a recent study which investigated the safety of vaccine schedules (present and past) using monkeys as test subjects.
The study is a follow on study to a previous series of pilot studies involving some of the same authors. The pilot studies were considered by many to be an indication of evidence that vaccines cause autism and other neurological conditions. This larger study shows no evidence of adverse effects from vaccines.
Here is the press release:
(Austin, Texas) – September 28, 2015 – New research finds no evidence that thimerosal- containing vaccines cause negative behaviors or result in neuropathology in infant primates, according to a study that will be published today in the Proceedings of the National Academy of Sciences. In this study, conducted by Dr. Dwight German of the University of Texas Southwestern School of Medicine, and colleagues, infant rhesus macaques received several pediatric vaccines containing thimerosal (a mercury-based preservative) in a schedule similar to that given to infants in the 1990s. Other animals received just the measles-mumps- rubella (MMR) vaccine, which does not contain thimerosal, or an expanded vaccine schedule similar to that recommended for US infants today. Control animals received a saline injection.
Regardless of vaccination status, all animals developed normal social behaviors. Cellular analysis of three brain regions, the cerebellum, amygdala and hippocampus (all known to be altered in autism), was similar in vaccinated and unvaccinated animals.
“This comprehensive analysis of social behavior and neuropathology in 12-18 month old rhesus macaques indicated that vaccinated primates were not negatively affected by thimerosal; the same was true for animals receiving an expanded 2008 vaccine schedule, which is similar to that recommended for US infants today” explained Dr. Laura Hewitson of The Johnson Center for Child Health and Development, one of the principle investigators working on the study. Hewitson was part of a team of researchers from The Johnson Center; the University of Texas Southwestern; the Center on Human Development and Disability Infant Primate Research Laboratory; the Washington National Primate Research Center (WaNPRC) at the University of Washington, Seattle WA; and Texas A&M Health Science Center & Central Texas Veterans Health Care System.
According to Hewitson, the study was designed to compare the safety of different vaccination schedules, including the schedule from the 1990s, when thimerosal was used as a preservative in multi-dose vaccine preparations. The data from this study indicate that administration of TCVs and/or the MMR vaccine to rhesus macaques did not result in neuropathological abnormalities,or aberrant behaviors, like those often observed in autism.
Administration of thimerosal-containing vaccines to infant rhesus macaques does not result in autism-like behavior or neuropathology. Bharathi S. Gadad, Wenhao Li, Umar Yazdani, Stephen Grady, Trevor Johnson, Jacob Hammond, Howard Gunn, Britni Curtis, Chris English, Vernon Yutuc, Clayton Ferrier, Gene P. Sackett, C. Nathan Marti, Keith Young, Laura Hewitson and Dwight C. German. PNAS
This article can be downloaded for free here.
This study was supported by The Ted Lindsay Foundation, SafeMinds, National Autism Association, and the Johnson and Vernick families. This work was also supported by WaNPRC Core Grant RR00166 and CHDD Core Grant HD02274.
About The Johnson Center
The mission of The Johnson Center for Child Health and Development is to advance the understanding of childhood development through clinical care, research, and education.
Previous Press Releases
For Immediate Release
By Matt Carey