Neurodevelopmental
disorders following thimerosal-containing childhood immunizations: a
follow-up analysis.
Geier D, Geier
MR.
MedCon, Inc., Maryland, USA.
The authors
previously published the first epidemiological study from the United
States associating thimerosal from childhood vaccines with
neurodevelopmental disorders (NDs) based upon assessment of the Vaccine
Adverse Event Reporting System (VAERS). A number of years have gone by
since their previous analysis of the VAERS. The present study was
undertaken to determine whether the previously observed effect between
thimerosal-containing childhood vaccines and NDs are still apparent in
the VAERS as children have had a chance to further mature and
potentially be diagnosed with additional NDs. In the present study, a
cohort of children receiving thimerosal-containing
diphtheria-tetanus-acellular pertussis (DTaP) vaccines in comparison to
a cohort of children receiving thimerosal-free DTaP vaccines
administered from 1997 through 2000 based upon an assessment of adverse
events reported to the VAERS were evaluated. It was determined that
there were significantly increased odds ratios (ORs) for autism (OR =
1.8, p < .05), mental retardation (OR = 2.6, p < .002), speech
disorder (OR = 2.1, p < .02), personality disorders (OR = 2.6, p <
.01), and thinking abnormality (OR = 8.2, p < .01) adverse events
reported to the VAERS following thimerosal-containing DTaP vaccines in
comparison to thimerosal-free DTaP vaccines. Potential confounders and
reporting biases were found to be minimal in this assessment of the
VAERS. It was observed, even though the media has reported a potential
association between autism and thimerosal exposure, that the other NDs
analyzed in this assessment of the VAERS had significantly higher ORs
than autism following thimerosal-containing DTaP vaccines in comparison
to thimerosal-free DTaP vaccines. The present study provides additional
epidemiological evidence supporting previous epidemiological, clinical
and experimental evidence that administration of thimerosal-containing
vaccines in the United States resulted in a significant number of
children developing NDs.