Delaying childhood vaccinations offer no benefit to children, and may be harmful

I’ve written in the past about the debate between doctors about delaying vaccines. This debate is based upon the fears among some parents that the current regimen of infant vaccinations involves too many vaccines too soon.

Then, to add to these fears came Dr. Robert Sears, a pediatrician in Capistrano Beach, Calif., who in October 2007, published “The Vaccine Book: Making the Right Decision for Your Child.” Included in Sears’ book was an alternative vaccine schedule that would allow parents to delay – and in some cases completely avoid – many vaccines for their children.

In 2009, the American Academy of Pediatrics (AAP) issued its updated childhood vaccination schedule, along with an article that deconstructs Sears’ popular and very controversial “delayed vaccine” schedule. Now to add to the AAP’s recommendations is a well-done study showing that delaying childhood vaccinations offers no benefit – and may cause some harms.

The Los Angeles Times “Booster Shots” blog reported, “Now that the thimerosal-autism link has been thoroughly discredited, some autism advocates argue that neurodevelopmental problems are caused by overloading children’s immune systems with too many vaccines too early in life.”

Consequently, a “growing number of parents are asking pediatricians to use alternative vaccination schedules that spread out the shots, even though there is no evidence to suggest that the practice may be helpful.” That evidence, however, may be hard to come by, as scientists “cannot ethically conduct a clinical trial of delayed vaccinations because of the potential risks to the children involved.”

To get around that issue, researchers at the University of Louisville School of Medicine decided to turn to data compiled through a project spearheaded by the CDC, the Wall Street Journal reports. Launched in 1990 with the help of eight managed care organizations, the Vaccine Safety Datalink project aimed to monitor safety and outcomes.

The current study authors zeroed in on 1,047 children who received shots between 1993 and 1997.

Between 2003 and 2004, all of the children were subjected to 42 tests, which, among other things, assessed their IQs, verbal abilities, and coordination, Reuters reported. The cohort was then grouped according to whether they received all of their inoculations within the first year of life or somehow failed to follow the schedule.

Specifically, “children were classified as up-to-date if they had received at least two hepatitis B, three diphtheria-tetanus-pertussis (DTP), three Haemophilus influenzae type B (Hib) and two polio vaccines on time during the first seven months of life,” HealthDay reported. ”

A vaccine was considered on time if it was given within 30 days of the recommended age.”

After conducting “two separate analyses,” the researchers “found no evidence to suggest that multiple vaccines in the first year of life negatively impact a child’s cognitive abilities later.

In fact, the first analysis revealed that children who received all their vaccines on time performed slightly better on two of the 42 tests,” whereas those “who missed or were late on one or more doses of vaccine didn’t do better on any test.”

Notably, “children getting vaccines later than doctors’ schedules were more likely to be from families with lower household incomes and had a lower percentage of mothers with college degrees,” WebMD reported.

In comparison, “those with on-time vaccinations were slightly younger at the time of neuropsychological assessment (mean 9.2 versus 9.4 years),” MedPage Today reported.

Nevertheless, “‘there was no evidence of neurodevelopmental delays or deficits associated with on-time vaccination,” Michael J. Smith, MD, MSCE, and Charles R. Woods, MD, MS, wrote in the study, which was published in Pediatrics.

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