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There are few subjects more divisive amongst parents than the debate over the wisdom and safety of giving the their children the growing list of vaccinations recommended by the CDC.
Despite numerous studies showing a sharp reduction in many serious childhood illnesses due to these vaccines a number of parents are now deciding to delay or forgo many of these pediatric vaccinations out of fears that too many vaccinations, too soon can cause developmental problems such as Autism.
Many of these fears have been stoked by anti-vaccine activists, including some doctors, who have warned of a theorized connection between the mercury compound thimerosal (used as a preservative) and later childhood mental development.
Out of an abundance of caution, despite no compelling evidence of a connection between autism and thimerosal, the FDA began urging drug manufacturers to phase out the controversial preservative from most childhood vaccines about a decade ago.
For those concerned over current mercury levels in these vaccines, the FDA maintains an excellent website with information on Thimerosal in Vaccines (many of which are now thimerosal free).
Today we’ve news of a new study, published in the Journal of Pediatrics, that may relieve some of the concerns that parents of kids who received these vaccines in the past might still have.
The study compares the mental development over 7 to 10 years of kids who received the recommended early vaccines, against those who either delayed receiving them, or skipped them altogether.
The authors found that infants who received the full regimen of shots did no worse developmentally (and in some cases did better), than children who skipped or delayed getting the shots.
First, a Reuters story on this study, followed by excerpts the journal abstract.
Many vaccines at once OK for kids' brains: study
NEW YORK (Reuters Health) - Parents can rest assured that getting kids their vaccine shots on time will not hurt their mental skills later on, doctors said on Monday.
"A lot of parents are concerned that children receive too many vaccines too soon," said Dr. Michael J. Smith, of the University of Louisville School of Medicine in Kentucky. Some parents skip recommended vaccines out of fear of autism, for instance, and some choose to space out shots.
Published online May 24, 2010
PEDIATRICS (doi:10.1542/peds.2009-2489)On-time Vaccine Receipt in the First Year Does Not Adversely Affect Neuropsychological Outcomes
Michael J. Smith, MD, MSCE, Charles R. Woods, MD, MSDivision of Pediatric Infectious Diseases, University of Louisville School of Medicine, Louisville, Kentucky
Objectives To determine whether children who received recommended vaccines on time during the first year of life had different neuropsychological outcomes at 7 to 10 years of age as compared with children with delayed receipt or nonreceipt of these vaccines.
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Results Timely vaccination was associated with better performance on 12 outcomes in univariate testing and remained associated with better performance for 2 outcomes in multivariable analyses. No statistically significant differences favored delayed receipt. In secondary analyses, children with the greatest vaccine exposure during the first 7 months of life performed better than children with the least vaccine exposure on 15 outcomes in univariate testing; these differences did not persist in multivariable analyses. No statistically significant differences favored the less vaccinated children.
Conclusions Timely vaccination during infancy has no adverse effect on neuropsychological outcomes 7 to 10 years later. These data may reassure parents who are concerned that children receive too many vaccines too soon.
