Vaccines

Neuropsychological performance 10 years after immunization in infancy with thimerosal-containing vaccines

Source: 
Pediatrics, Tozzi AE, Bisiacchi P, Tarantino V, De Mei B, D'Elia L, Chariotti F, Salmaso S.
Date Published: 
January 2009
Year Published: 
2009

Thimerosal, a mercury compound used as a preservative in vaccines administered during infancy, has been suspected to affect neuropsychological development. We compared the neuropsychological performance, 10 years after vaccination, of 2 groups of children exposed randomly to different amounts of thimerosal through immunization. Children who were enrolled in an efficacy trial of pertussis vaccines in 1992–1993 were contacted in 2003. Two groups of children were identified, according to thimerosal content in vaccines assigned randomly in the first year of life (cumulative ethylmercury intake of 62.5 or 137.5 µg), and were compared with respect to neuropsychological outcomes. Eleven standardized neuropsychological tests, for a total of 24 outcomes, were administered to children during school hours. Mean scores of neuropsychological tests in the domains of memory and learning, attention, executive functions, visuospatial functions, language, and motor skills were compared according to thimerosal exposure and gender. Nearly 70% of the invited subjects participated in the neuropsychological assessment (N = 1403). Among the 24 neuropsychological outcomes that were evaluated, only 2 were significantly associated with thimerosal exposure. Girls with higher thimerosal intake had lower mean scores in the finger-tapping test with the dominant hand and in the Boston Naming Test. Given the large number of statistical comparisons performed, the few associations found between thimerosal exposure and neuropsychological development might be attributable to chance. The associations found, although statistically significant, were based on small differences in mean test scores, and their clinical relevance remains to be determined.

Thimerosal Disappears but Autism Remains

Source: 
Archives of General Psychiatry, Fombonne
Date Published: 
2008
Year Published: 
2008

 

Parents of autistic children should be reassured that autism in their child did not occur through immunizations. Their autistic children, and their siblings, should be normally vaccinated, and as there is no evidence of mercury poisoning in autism, they should avoid ineffective and dangerous
"treatments" such as chelation therapy for their children.

Lack of Association between Measles Virus Vaccine and Autism with Enteropathy: A Case-Control Study

Source: 
PLOS ONE, Hornig, Briese, et al
Date Published: 
2008

This study provides strong evidence against association of autism with persistent MV RNA in the GI tract or MMR exposure. Autism with GI disturbances is associated with elevated rates of regression in language or other skills and may represent an endophenotype distinct from other ASD.

Continuing Increases in Autism Reported to California’s Developmental Services System: Mercury in Retrograde

Source: 
Archives of General Psychiatry, Schechter, Grether
Date Published: 
2008
Year Published: 
2008

California Department of Developmental Services (DDS) data do not show any recent decrease in autism in California despite the exclusion of more than trace levels of thimerosal from nearly all childhood vaccines. The DDS data do not support the hypothesis that exposure to thimerosal during childhood is a primary cause of autism.