Delayed Vaccine Update

Delaying childhood vaccinations may offer no benefit.
The Los Angeles Times (5/24, Maugh) "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 (5/25, Dooren) 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 (5/24, Joelving) 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 (5/24, Behen) 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 (5/24, Hendrick) 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 (5/24, Gever) 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 a study published online May 24 in Pediatrics.